forked from MTSR/telegram
1725 lines
62 KiB
Lua
1725 lines
62 KiB
Lua
-- -*- coding: utf-8 -*-
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--
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-- Simple JSON encoding and decoding in pure Lua.
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--
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-- Copyright 2010-2017 Jeffrey Friedl
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-- http://regex.info/blog/
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-- Latest version: http://regex.info/blog/lua/json
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--
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-- This code is released under a Creative Commons CC-BY "Attribution" License:
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-- http://creativecommons.org/licenses/by/3.0/deed.en_US
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--
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-- It can be used for any purpose so long as:
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-- 1) the copyright notice above is maintained
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-- 2) the web-page links above are maintained
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-- 3) the 'AUTHOR_NOTE' string below is maintained
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--
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local VERSION = '20170927.26' -- version history at end of file
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local AUTHOR_NOTE = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json) version 20170927.26 ]-"
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--
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-- The 'AUTHOR_NOTE' variable exists so that information about the source
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-- of the package is maintained even in compiled versions. It's also
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-- included in OBJDEF below mostly to quiet warnings about unused variables.
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--
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local OBJDEF = {
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VERSION = VERSION,
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AUTHOR_NOTE = AUTHOR_NOTE,
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}
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--
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-- Simple JSON encoding and decoding in pure Lua.
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-- JSON definition: http://www.json.org/
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--
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local lua_value = JSON:decode(raw_json_text)
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--
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-- local raw_json_text = JSON:encode(lua_table_or_value)
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-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
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--
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--
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--
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-- DECODING (from a JSON string to a Lua table)
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--
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local lua_value = JSON:decode(raw_json_text)
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--
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-- If the JSON text is for an object or an array, e.g.
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-- { "what": "books", "count": 3 }
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-- or
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-- [ "Larry", "Curly", "Moe" ]
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--
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-- the result is a Lua table, e.g.
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-- { what = "books", count = 3 }
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-- or
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-- { "Larry", "Curly", "Moe" }
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--
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--
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-- The encode and decode routines accept an optional second argument,
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-- "etc", which is not used during encoding or decoding, but upon error
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-- is passed along to error handlers. It can be of any type (including nil).
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--
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--
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--
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-- ERROR HANDLING DURING DECODE
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--
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-- With most errors during decoding, this code calls
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--
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-- JSON:onDecodeError(message, text, location, etc)
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--
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-- with a message about the error, and if known, the JSON text being
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-- parsed and the byte count where the problem was discovered. You can
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-- replace the default JSON:onDecodeError() with your own function.
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--
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-- The default onDecodeError() merely augments the message with data
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-- about the text and the location (and, an 'etc' argument had been
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-- provided to decode(), its value is tacked onto the message as well),
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-- and then calls JSON.assert(), which itself defaults to Lua's built-in
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-- assert(), and can also be overridden.
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--
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-- For example, in an Adobe Lightroom plugin, you might use something like
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--
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-- function JSON:onDecodeError(message, text, location, etc)
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-- LrErrors.throwUserError("Internal Error: invalid JSON data")
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-- end
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--
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-- or even just
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--
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-- function JSON.assert(message)
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-- LrErrors.throwUserError("Internal Error: " .. message)
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-- end
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--
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-- If JSON:decode() is passed a nil, this is called instead:
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--
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-- JSON:onDecodeOfNilError(message, nil, nil, etc)
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--
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-- and if JSON:decode() is passed HTML instead of JSON, this is called:
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--
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-- JSON:onDecodeOfHTMLError(message, text, nil, etc)
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--
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-- The use of the 'etc' argument allows stronger coordination between
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-- decoding and error reporting, especially when you provide your own
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-- error-handling routines. Continuing with the the Adobe Lightroom
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-- plugin example:
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--
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-- function JSON:onDecodeError(message, text, location, etc)
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-- local note = "Internal Error: invalid JSON data"
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-- if type(etc) = 'table' and etc.photo then
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-- note = note .. " while processing for " .. etc.photo:getFormattedMetadata('fileName')
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-- end
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-- LrErrors.throwUserError(note)
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-- end
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--
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-- :
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-- :
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--
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-- for i, photo in ipairs(photosToProcess) do
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-- :
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-- :
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-- local data = JSON:decode(someJsonText, { photo = photo })
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-- :
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-- :
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-- end
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--
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--
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--
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-- If the JSON text passed to decode() has trailing garbage (e.g. as with the JSON "[123]xyzzy"),
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-- the method
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--
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-- JSON:onTrailingGarbage(json_text, location, parsed_value, etc)
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--
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-- is invoked, where:
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--
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-- 'json_text' is the original JSON text being parsed,
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-- 'location' is the count of bytes into 'json_text' where the garbage starts (6 in the example),
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-- 'parsed_value' is the Lua result of what was successfully parsed ({123} in the example),
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-- 'etc' is as above.
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--
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-- If JSON:onTrailingGarbage() does not abort, it should return the value decode() should return,
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-- or nil + an error message.
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--
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-- local new_value, error_message = JSON:onTrailingGarbage()
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--
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-- The default JSON:onTrailingGarbage() simply invokes JSON:onDecodeError("trailing garbage"...),
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-- but you can have this package ignore trailing garbage via
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--
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-- function JSON:onTrailingGarbage(json_text, location, parsed_value, etc)
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-- return parsed_value
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-- end
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--
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--
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-- DECODING AND STRICT TYPES
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--
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-- Because both JSON objects and JSON arrays are converted to Lua tables,
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-- it's not normally possible to tell which original JSON type a
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-- particular Lua table was derived from, or guarantee decode-encode
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-- round-trip equivalency.
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--
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-- However, if you enable strictTypes, e.g.
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--
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-- JSON = assert(loadfile "JSON.lua")() --load the routines
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-- JSON.strictTypes = true
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--
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-- then the Lua table resulting from the decoding of a JSON object or
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-- JSON array is marked via Lua metatable, so that when re-encoded with
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-- JSON:encode() it ends up as the appropriate JSON type.
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--
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-- (This is not the default because other routines may not work well with
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-- tables that have a metatable set, for example, Lightroom API calls.)
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--
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--
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-- ENCODING (from a lua table to a JSON string)
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--
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-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
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--
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-- local raw_json_text = JSON:encode(lua_table_or_value)
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-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
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-- local custom_pretty = JSON:encode(lua_table_or_value, etc, { pretty = true, indent = "| ", align_keys = false })
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--
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-- On error during encoding, this code calls:
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--
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-- JSON:onEncodeError(message, etc)
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--
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-- which you can override in your local JSON object. Also see "HANDLING UNSUPPORTED VALUE TYPES" below.
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--
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-- The 'etc' in the error call is the second argument to encode() and encode_pretty(), or nil if it wasn't provided.
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--
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--
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--
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--
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-- ENCODING OPTIONS
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--
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-- An optional third argument, a table of options, can be provided to encode().
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--
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-- encode_options = {
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-- -- options for making "pretty" human-readable JSON (see "PRETTY-PRINTING" below)
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-- pretty = true, -- turn pretty formatting on
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-- indent = " ", -- use this indent for each level of an array/object
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-- align_keys = false, -- if true, align the keys in a way that sounds like it should be nice, but is actually ugly
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-- array_newline = false, -- if true, array elements become one to a line rather than inline
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--
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-- -- other output-related options
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-- null = "\0", -- see "ENCODING JSON NULL VALUES" below
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-- stringsAreUtf8 = false, -- see "HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA" below
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-- }
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--
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-- json_string = JSON:encode(mytable, etc, encode_options)
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--
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--
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--
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-- For reference, the defaults are:
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--
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-- pretty = false
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-- null = nil,
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-- stringsAreUtf8 = false,
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--
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--
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--
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-- PRETTY-PRINTING
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--
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-- Enabling the 'pretty' encode option helps generate human-readable JSON.
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--
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-- pretty = JSON:encode(val, etc, {
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-- pretty = true,
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-- indent = " ",
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-- align_keys = false,
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-- })
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--
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-- encode_pretty() is also provided: it's identical to encode() except
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-- that encode_pretty() provides a default options table if none given in the call:
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--
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-- { pretty = true, indent = " ", align_keys = false, array_newline = false }
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--
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-- For example, if
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--
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-- JSON:encode(data)
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--
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-- produces:
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--
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-- {"city":"Kyoto","climate":{"avg_temp":16,"humidity":"high","snowfall":"minimal"},"country":"Japan","wards":11}
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--
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-- then
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--
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-- JSON:encode_pretty(data)
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--
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-- produces:
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--
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-- {
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-- "city": "Kyoto",
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-- "climate": {
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-- "avg_temp": 16,
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-- "humidity": "high",
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-- "snowfall": "minimal"
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-- },
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-- "country": "Japan",
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-- "wards": 11
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-- }
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--
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-- The following lines all return identical strings:
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-- JSON:encode_pretty(data)
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = " ", align_keys = false, array_newline = false})
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = " " })
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-- JSON:encode (data, nil, { pretty = true, indent = " " })
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--
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-- An example of setting your own indent string:
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--
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = "| " })
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--
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-- produces:
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--
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-- {
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-- | "city": "Kyoto",
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-- | "climate": {
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-- | | "avg_temp": 16,
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-- | | "humidity": "high",
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-- | | "snowfall": "minimal"
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-- | },
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-- | "country": "Japan",
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-- | "wards": 11
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-- }
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--
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-- An example of setting align_keys to true:
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--
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-- JSON:encode_pretty(data, nil, { pretty = true, indent = " ", align_keys = true })
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--
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-- produces:
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--
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-- {
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-- "city": "Kyoto",
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-- "climate": {
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-- "avg_temp": 16,
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-- "humidity": "high",
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-- "snowfall": "minimal"
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-- },
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-- "country": "Japan",
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-- "wards": 11
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-- }
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--
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-- which I must admit is kinda ugly, sorry. This was the default for
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-- encode_pretty() prior to version 20141223.14.
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--
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--
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-- HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA
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--
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-- If the 'stringsAreUtf8' encode option is set to true, consider Lua strings not as a sequence of bytes,
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-- but as a sequence of UTF-8 characters.
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--
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-- Currently, the only practical effect of setting this option is that Unicode LINE and PARAGRAPH
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-- separators, if found in a string, are encoded with a JSON escape instead of being dumped as is.
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-- The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
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-- to also be valid Java.
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--
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-- AMBIGUOUS SITUATIONS DURING THE ENCODING
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--
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-- During the encode, if a Lua table being encoded contains both string
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-- and numeric keys, it fits neither JSON's idea of an object, nor its
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-- idea of an array. To get around this, when any string key exists (or
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-- when non-positive numeric keys exist), numeric keys are converted to
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-- strings.
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--
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-- For example,
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-- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" }))
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-- produces the JSON object
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-- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"}
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--
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-- To prohibit this conversion and instead make it an error condition, set
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-- JSON.noKeyConversion = true
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--
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--
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-- ENCODING JSON NULL VALUES
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--
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-- Lua tables completely omit keys whose value is nil, so without special handling there's
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-- no way to represent JSON object's null value in a Lua table. For example
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-- JSON:encode({ username = "admin", password = nil })
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--
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-- produces:
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--
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-- {"username":"admin"}
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--
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-- In order to actually produce
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--
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-- {"username":"admin", "password":null}
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--
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-- one can include a string value for a "null" field in the options table passed to encode()....
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-- any Lua table entry with that value becomes null in the JSON output:
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--
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-- JSON:encode({ username = "admin", password = "xyzzy" }, -- First arg is the Lua table to encode as JSON.
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-- nil, -- Second arg is the 'etc' value, ignored here
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-- { null = "xyzzy" }) -- Third arg is th options table
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--
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-- produces:
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--
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-- {"username":"admin", "password":null}
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--
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-- Just be sure to use a string that is otherwise unlikely to appear in your data.
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-- The string "\0" (a string with one null byte) may well be appropriate for many applications.
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--
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-- The "null" options also applies to Lua tables that become JSON arrays.
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-- JSON:encode({ "one", "two", nil, nil })
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--
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-- produces
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--
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-- ["one","two"]
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--
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-- while
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--
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-- NullPlaceholder = "\0"
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-- encode_options = { null = NullPlaceholder }
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-- JSON:encode({ "one", "two", NullPlaceholder, NullPlaceholder}, nil, encode_options)
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-- produces
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--
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-- ["one","two",null,null]
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--
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--
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--
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-- HANDLING LARGE AND/OR PRECISE NUMBERS
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--
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--
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-- Without special handling, numbers in JSON can lose precision in Lua.
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-- For example:
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--
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-- T = JSON:decode('{ "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345 }')
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--
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-- print("small: ", type(T.small), T.small)
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-- print("big: ", type(T.big), T.big)
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-- print("precise: ", type(T.precise), T.precise)
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--
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-- produces
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--
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-- small: number 12345
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-- big: number 1.2345678901235e+28
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-- precise: number 9876.6789012346
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--
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-- Precision is lost with both 'big' and 'precise'.
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--
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-- This package offers ways to try to handle this better (for some definitions of "better")...
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--
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-- The most precise method is by setting the global:
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--
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-- JSON.decodeNumbersAsObjects = true
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--
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-- When this is set, numeric JSON data is encoded into Lua in a form that preserves the exact
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-- JSON numeric presentation when re-encoded back out to JSON, or accessed in Lua as a string.
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--
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-- This is done by encoding the numeric data with a Lua table/metatable that returns
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-- the possibly-imprecise numeric form when accessed numerically, but the original precise
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-- representation when accessed as a string.
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--
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-- Consider the example above, with this option turned on:
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--
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-- JSON.decodeNumbersAsObjects = true
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--
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-- T = JSON:decode('{ "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345 }')
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--
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-- print("small: ", type(T.small), T.small)
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-- print("big: ", type(T.big), T.big)
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-- print("precise: ", type(T.precise), T.precise)
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--
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-- This now produces:
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--
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-- small: table 12345
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-- big: table 12345678901234567890123456789
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-- precise: table 9876.67890123456789012345
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--
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-- However, within Lua you can still use the values (e.g. T.precise in the example above) in numeric
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-- contexts. In such cases you'll get the possibly-imprecise numeric version, but in string contexts
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-- and when the data finds its way to this package's encode() function, the original full-precision
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-- representation is used.
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--
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-- You can force access to the string or numeric version via
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-- JSON:forceString()
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-- JSON:forceNumber()
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-- For example,
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-- local probably_okay = JSON:forceNumber(T.small) -- 'probably_okay' is a number
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--
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-- Code the inspects the JSON-turned-Lua data using type() can run into troubles because what used to
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-- be a number can now be a table (e.g. as the small/big/precise example above shows). Update these
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-- situations to use JSON:isNumber(item), which returns nil if the item is neither a number nor one
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-- of these number objects. If it is either, it returns the number itself. For completeness there's
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-- also JSON:isString(item).
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--
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-- If you want to try to avoid the hassles of this "number as an object" kludge for all but really
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-- big numbers, you can set JSON.decodeNumbersAsObjects and then also set one or both of
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-- JSON:decodeIntegerObjectificationLength
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-- JSON:decodeDecimalObjectificationLength
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-- They refer to the length of the part of the number before and after a decimal point. If they are
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-- set and their part is at least that number of digits, objectification occurs. If both are set,
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-- objectification occurs when either length is met.
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--
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-- -----------------------
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--
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-- Even without using the JSON.decodeNumbersAsObjects option, you can encode numbers in your Lua
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-- table that retain high precision upon encoding to JSON, by using the JSON:asNumber() function:
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--
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-- T = {
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-- imprecise = 123456789123456789.123456789123456789,
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-- precise = JSON:asNumber("123456789123456789.123456789123456789")
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-- }
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--
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-- print(JSON:encode_pretty(T))
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--
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-- This produces:
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--
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-- {
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-- "precise": 123456789123456789.123456789123456789,
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-- "imprecise": 1.2345678912346e+17
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-- }
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--
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--
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-- -----------------------
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--
|
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-- A different way to handle big/precise JSON numbers is to have decode() merely return the exact
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-- string representation of the number instead of the number itself. This approach might be useful
|
|
-- when the numbers are merely some kind of opaque object identifier and you want to work with them
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-- in Lua as strings anyway.
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--
|
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-- This approach is enabled by setting
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--
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-- JSON.decodeIntegerStringificationLength = 10
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--
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-- The value is the number of digits (of the integer part of the number) at which to stringify numbers.
|
|
-- NOTE: this setting is ignored if JSON.decodeNumbersAsObjects is true, as that takes precedence.
|
|
--
|
|
-- Consider our previous example with this option set to 10:
|
|
--
|
|
-- JSON.decodeIntegerStringificationLength = 10
|
|
--
|
|
-- T = JSON:decode('{ "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345 }')
|
|
--
|
|
-- print("small: ", type(T.small), T.small)
|
|
-- print("big: ", type(T.big), T.big)
|
|
-- print("precise: ", type(T.precise), T.precise)
|
|
--
|
|
-- This produces:
|
|
--
|
|
-- small: number 12345
|
|
-- big: string 12345678901234567890123456789
|
|
-- precise: number 9876.6789012346
|
|
--
|
|
-- The long integer of the 'big' field is at least JSON.decodeIntegerStringificationLength digits
|
|
-- in length, so it's converted not to a Lua integer but to a Lua string. Using a value of 0 or 1 ensures
|
|
-- that all JSON numeric data becomes strings in Lua.
|
|
--
|
|
-- Note that unlike
|
|
-- JSON.decodeNumbersAsObjects = true
|
|
-- this stringification is simple and unintelligent: the JSON number simply becomes a Lua string, and that's the end of it.
|
|
-- If the string is then converted back to JSON, it's still a string. After running the code above, adding
|
|
-- print(JSON:encode(T))
|
|
-- produces
|
|
-- {"big":"12345678901234567890123456789","precise":9876.6789012346,"small":12345}
|
|
-- which is unlikely to be desired.
|
|
--
|
|
-- There's a comparable option for the length of the decimal part of a number:
|
|
--
|
|
-- JSON.decodeDecimalStringificationLength
|
|
--
|
|
-- This can be used alone or in conjunction with
|
|
--
|
|
-- JSON.decodeIntegerStringificationLength
|
|
--
|
|
-- to trip stringification on precise numbers with at least JSON.decodeIntegerStringificationLength digits after
|
|
-- the decimal point. (Both are ignored if JSON.decodeNumbersAsObjects is true.)
|
|
--
|
|
-- This example:
|
|
--
|
|
-- JSON.decodeIntegerStringificationLength = 10
|
|
-- JSON.decodeDecimalStringificationLength = 5
|
|
--
|
|
-- T = JSON:decode('{ "small":12345, "big":12345678901234567890123456789, "precise":9876.67890123456789012345 }')
|
|
--
|
|
-- print("small: ", type(T.small), T.small)
|
|
-- print("big: ", type(T.big), T.big)
|
|
-- print("precise: ", type(T.precise), T.precise)
|
|
--
|
|
-- produces:
|
|
--
|
|
-- small: number 12345
|
|
-- big: string 12345678901234567890123456789
|
|
-- precise: string 9876.67890123456789012345
|
|
--
|
|
--
|
|
-- HANDLING UNSUPPORTED VALUE TYPES
|
|
--
|
|
-- Among the encoding errors that might be raised is an attempt to convert a table value that has a type
|
|
-- that this package hasn't accounted for: a function, userdata, or a thread. You can handle these types as table
|
|
-- values (but not as table keys) if you supply a JSON:unsupportedTypeEncoder() method along the lines of the
|
|
-- following example:
|
|
--
|
|
-- function JSON:unsupportedTypeEncoder(value_of_unsupported_type)
|
|
-- if type(value_of_unsupported_type) == 'function' then
|
|
-- return "a function value"
|
|
-- else
|
|
-- return nil
|
|
-- end
|
|
-- end
|
|
--
|
|
-- Your unsupportedTypeEncoder() method is actually called with a bunch of arguments:
|
|
--
|
|
-- self:unsupportedTypeEncoder(value, parents, etc, options, indent, for_key)
|
|
--
|
|
-- The 'value' is the function, thread, or userdata to be converted to JSON.
|
|
--
|
|
-- The 'etc' and 'options' arguments are those passed to the original encode(). The other arguments are
|
|
-- probably of little interest; see the source code. (Note that 'for_key' is never true, as this function
|
|
-- is invoked only on table values; table keys of these types still trigger the onEncodeError method.)
|
|
--
|
|
-- If your unsupportedTypeEncoder() method returns a string, it's inserted into the JSON as is.
|
|
-- If it returns nil plus an error message, that error message is passed through to an onEncodeError invocation.
|
|
-- If it returns only nil, processing falls through to a default onEncodeError invocation.
|
|
--
|
|
-- If you want to handle everything in a simple way:
|
|
--
|
|
-- function JSON:unsupportedTypeEncoder(value)
|
|
-- return tostring(value)
|
|
-- end
|
|
--
|
|
--
|
|
-- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT
|
|
--
|
|
-- assert
|
|
-- onDecodeError
|
|
-- onDecodeOfNilError
|
|
-- onDecodeOfHTMLError
|
|
-- onTrailingGarbage
|
|
-- onEncodeError
|
|
-- unsupportedTypeEncoder
|
|
--
|
|
-- If you want to create a separate Lua JSON object with its own error handlers,
|
|
-- you can reload JSON.lua or use the :new() method.
|
|
--
|
|
---------------------------------------------------------------------------
|
|
|
|
local default_pretty_indent = " "
|
|
local default_pretty_options = { pretty = true, indent = default_pretty_indent, align_keys = false, array_newline = false }
|
|
|
|
local isArray = { __tostring = function() return "JSON array" end } isArray.__index = isArray
|
|
local isObject = { __tostring = function() return "JSON object" end } isObject.__index = isObject
|
|
|
|
function OBJDEF:newArray(tbl)
|
|
return setmetatable(tbl or {}, isArray)
|
|
end
|
|
|
|
function OBJDEF:newObject(tbl)
|
|
return setmetatable(tbl or {}, isObject)
|
|
end
|
|
|
|
|
|
|
|
|
|
local function getnum(op)
|
|
return type(op) == 'number' and op or op.N
|
|
end
|
|
|
|
local isNumber = {
|
|
__tostring = function(T) return T.S end,
|
|
__unm = function(op) return getnum(op) end,
|
|
|
|
__concat = function(op1, op2) return tostring(op1) .. tostring(op2) end,
|
|
__add = function(op1, op2) return getnum(op1) + getnum(op2) end,
|
|
__sub = function(op1, op2) return getnum(op1) - getnum(op2) end,
|
|
__mul = function(op1, op2) return getnum(op1) * getnum(op2) end,
|
|
__div = function(op1, op2) return getnum(op1) / getnum(op2) end,
|
|
__mod = function(op1, op2) return getnum(op1) % getnum(op2) end,
|
|
__pow = function(op1, op2) return getnum(op1) ^ getnum(op2) end,
|
|
__lt = function(op1, op2) return getnum(op1) < getnum(op2) end,
|
|
__eq = function(op1, op2) return getnum(op1) == getnum(op2) end,
|
|
__le = function(op1, op2) return getnum(op1) <= getnum(op2) end,
|
|
}
|
|
isNumber.__index = isNumber
|
|
|
|
function OBJDEF:asNumber(item)
|
|
|
|
if getmetatable(item) == isNumber then
|
|
-- it's already a JSON number object.
|
|
return item
|
|
elseif type(item) == 'table' and type(item.S) == 'string' and type(item.N) == 'number' then
|
|
-- it's a number-object table that lost its metatable, so give it one
|
|
return setmetatable(item, isNumber)
|
|
else
|
|
-- the normal situation... given a number or a string representation of a number....
|
|
local holder = {
|
|
S = tostring(item), -- S is the representation of the number as a string, which remains precise
|
|
N = tonumber(item), -- N is the number as a Lua number.
|
|
}
|
|
return setmetatable(holder, isNumber)
|
|
end
|
|
end
|
|
|
|
--
|
|
-- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
|
|
-- return the string version. This shouldn't be needed often because the 'isNumber' object should autoconvert
|
|
-- to a string in most cases, but it's here to allow it to be forced when needed.
|
|
--
|
|
function OBJDEF:forceString(item)
|
|
if type(item) == 'table' and type(item.S) == 'string' then
|
|
return item.S
|
|
else
|
|
return tostring(item)
|
|
end
|
|
end
|
|
|
|
--
|
|
-- Given an item that might be a normal string or number, or might be an 'isNumber' object defined above,
|
|
-- return the numeric version.
|
|
--
|
|
function OBJDEF:forceNumber(item)
|
|
if type(item) == 'table' and type(item.N) == 'number' then
|
|
return item.N
|
|
else
|
|
return tonumber(item)
|
|
end
|
|
end
|
|
|
|
--
|
|
-- If the given item is a number, return it. Otherwise, return nil.
|
|
-- This, this can be used both in a conditional and to access the number when you're not sure its form.
|
|
--
|
|
function OBJDEF:isNumber(item)
|
|
if type(item) == 'number' then
|
|
return item
|
|
elseif type(item) == 'table' and type(item.N) == 'number' then
|
|
return item.N
|
|
else
|
|
return nil
|
|
end
|
|
end
|
|
|
|
function OBJDEF:isString(item)
|
|
if type(item) == 'string' then
|
|
return item
|
|
elseif type(item) == 'table' and type(item.S) == 'string' then
|
|
return item.S
|
|
else
|
|
return nil
|
|
end
|
|
end
|
|
|
|
|
|
local function unicode_codepoint_as_utf8(codepoint)
|
|
--
|
|
-- codepoint is a number
|
|
--
|
|
if codepoint <= 127 then
|
|
return string.char(codepoint)
|
|
|
|
elseif codepoint <= 2047 then
|
|
--
|
|
-- 110yyyxx 10xxxxxx <-- useful notation from http://en.wikipedia.org/wiki/Utf8
|
|
--
|
|
local highpart = math.floor(codepoint / 0x40)
|
|
local lowpart = codepoint - (0x40 * highpart)
|
|
return string.char(0xC0 + highpart,
|
|
0x80 + lowpart)
|
|
|
|
elseif codepoint <= 65535 then
|
|
--
|
|
-- 1110yyyy 10yyyyxx 10xxxxxx
|
|
--
|
|
local highpart = math.floor(codepoint / 0x1000)
|
|
local remainder = codepoint - 0x1000 * highpart
|
|
local midpart = math.floor(remainder / 0x40)
|
|
local lowpart = remainder - 0x40 * midpart
|
|
|
|
highpart = 0xE0 + highpart
|
|
midpart = 0x80 + midpart
|
|
lowpart = 0x80 + lowpart
|
|
|
|
--
|
|
-- Check for an invalid character (thanks Andy R. at Adobe).
|
|
-- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070
|
|
--
|
|
if ( highpart == 0xE0 and midpart < 0xA0 ) or
|
|
( highpart == 0xED and midpart > 0x9F ) or
|
|
( highpart == 0xF0 and midpart < 0x90 ) or
|
|
( highpart == 0xF4 and midpart > 0x8F )
|
|
then
|
|
return "?"
|
|
else
|
|
return string.char(highpart,
|
|
midpart,
|
|
lowpart)
|
|
end
|
|
|
|
else
|
|
--
|
|
-- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx
|
|
--
|
|
local highpart = math.floor(codepoint / 0x40000)
|
|
local remainder = codepoint - 0x40000 * highpart
|
|
local midA = math.floor(remainder / 0x1000)
|
|
remainder = remainder - 0x1000 * midA
|
|
local midB = math.floor(remainder / 0x40)
|
|
local lowpart = remainder - 0x40 * midB
|
|
|
|
return string.char(0xF0 + highpart,
|
|
0x80 + midA,
|
|
0x80 + midB,
|
|
0x80 + lowpart)
|
|
end
|
|
end
|
|
|
|
function OBJDEF:onDecodeError(message, text, location, etc)
|
|
if text then
|
|
if location then
|
|
message = string.format("%s at byte %d of: %s", message, location, text)
|
|
else
|
|
message = string.format("%s: %s", message, text)
|
|
end
|
|
end
|
|
|
|
if etc ~= nil then
|
|
message = message .. " (" .. OBJDEF:encode(etc) .. ")"
|
|
end
|
|
|
|
if self.assert then
|
|
self.assert(false, message)
|
|
else
|
|
assert(false, message)
|
|
end
|
|
end
|
|
|
|
function OBJDEF:onTrailingGarbage(json_text, location, parsed_value, etc)
|
|
return self:onDecodeError("trailing garbage", json_text, location, etc)
|
|
end
|
|
|
|
OBJDEF.onDecodeOfNilError = OBJDEF.onDecodeError
|
|
OBJDEF.onDecodeOfHTMLError = OBJDEF.onDecodeError
|
|
|
|
function OBJDEF:onEncodeError(message, etc)
|
|
if etc ~= nil then
|
|
message = message .. " (" .. OBJDEF:encode(etc) .. ")"
|
|
end
|
|
|
|
if self.assert then
|
|
self.assert(false, message)
|
|
else
|
|
assert(false, message)
|
|
end
|
|
end
|
|
|
|
local function grok_number(self, text, start, options)
|
|
--
|
|
-- Grab the integer part
|
|
--
|
|
local integer_part = text:match('^-?[1-9]%d*', start)
|
|
or text:match("^-?0", start)
|
|
|
|
if not integer_part then
|
|
self:onDecodeError("expected number", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local i = start + integer_part:len()
|
|
|
|
--
|
|
-- Grab an optional decimal part
|
|
--
|
|
local decimal_part = text:match('^%.%d+', i) or ""
|
|
|
|
i = i + decimal_part:len()
|
|
|
|
--
|
|
-- Grab an optional exponential part
|
|
--
|
|
local exponent_part = text:match('^[eE][-+]?%d+', i) or ""
|
|
|
|
i = i + exponent_part:len()
|
|
|
|
local full_number_text = integer_part .. decimal_part .. exponent_part
|
|
|
|
if options.decodeNumbersAsObjects then
|
|
|
|
local objectify = false
|
|
|
|
if not options.decodeIntegerObjectificationLength and not options.decodeDecimalObjectificationLength then
|
|
-- no options, so objectify
|
|
objectify = true
|
|
|
|
elseif (options.decodeIntegerObjectificationLength
|
|
and
|
|
(integer_part:len() >= options.decodeIntegerObjectificationLength or exponent_part:len() > 0))
|
|
|
|
or
|
|
(options.decodeDecimalObjectificationLength
|
|
and
|
|
(decimal_part:len() >= options.decodeDecimalObjectificationLength or exponent_part:len() > 0))
|
|
then
|
|
-- have options and they are triggered, so objectify
|
|
objectify = true
|
|
end
|
|
|
|
if objectify then
|
|
return OBJDEF:asNumber(full_number_text), i
|
|
end
|
|
-- else, fall through to try to return as a straight-up number
|
|
|
|
else
|
|
|
|
-- Not always decoding numbers as objects, so perhaps encode as strings?
|
|
|
|
--
|
|
-- If we're told to stringify only under certain conditions, so do.
|
|
-- We punt a bit when there's an exponent by just stringifying no matter what.
|
|
-- I suppose we should really look to see whether the exponent is actually big enough one
|
|
-- way or the other to trip stringification, but I'll be lazy about it until someone asks.
|
|
--
|
|
if (options.decodeIntegerStringificationLength
|
|
and
|
|
(integer_part:len() >= options.decodeIntegerStringificationLength or exponent_part:len() > 0))
|
|
|
|
or
|
|
|
|
(options.decodeDecimalStringificationLength
|
|
and
|
|
(decimal_part:len() >= options.decodeDecimalStringificationLength or exponent_part:len() > 0))
|
|
then
|
|
return full_number_text, i -- this returns the exact string representation seen in the original JSON
|
|
end
|
|
|
|
end
|
|
|
|
|
|
local as_number = tonumber(full_number_text)
|
|
|
|
if not as_number then
|
|
self:onDecodeError("bad number", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
return as_number, i
|
|
end
|
|
|
|
|
|
local function grok_string(self, text, start, options)
|
|
|
|
if text:sub(start,start) ~= '"' then
|
|
self:onDecodeError("expected string's opening quote", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local i = start + 1 -- +1 to bypass the initial quote
|
|
local text_len = text:len()
|
|
local VALUE = ""
|
|
while i <= text_len do
|
|
local c = text:sub(i,i)
|
|
if c == '"' then
|
|
return VALUE, i + 1
|
|
end
|
|
if c ~= '\\' then
|
|
VALUE = VALUE .. c
|
|
i = i + 1
|
|
elseif text:match('^\\b', i) then
|
|
VALUE = VALUE .. "\b"
|
|
i = i + 2
|
|
elseif text:match('^\\f', i) then
|
|
VALUE = VALUE .. "\f"
|
|
i = i + 2
|
|
elseif text:match('^\\n', i) then
|
|
VALUE = VALUE .. "\n"
|
|
i = i + 2
|
|
elseif text:match('^\\r', i) then
|
|
VALUE = VALUE .. "\r"
|
|
i = i + 2
|
|
elseif text:match('^\\t', i) then
|
|
VALUE = VALUE .. "\t"
|
|
i = i + 2
|
|
else
|
|
local hex = text:match('^\\u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
|
|
if hex then
|
|
i = i + 6 -- bypass what we just read
|
|
|
|
-- We have a Unicode codepoint. It could be standalone, or if in the proper range and
|
|
-- followed by another in a specific range, it'll be a two-code surrogate pair.
|
|
local codepoint = tonumber(hex, 16)
|
|
if codepoint >= 0xD800 and codepoint <= 0xDBFF then
|
|
-- it's a hi surrogate... see whether we have a following low
|
|
local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i)
|
|
if lo_surrogate then
|
|
i = i + 6 -- bypass the low surrogate we just read
|
|
codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16)
|
|
else
|
|
-- not a proper low, so we'll just leave the first codepoint as is and spit it out.
|
|
end
|
|
end
|
|
VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint)
|
|
|
|
else
|
|
|
|
-- just pass through what's escaped
|
|
VALUE = VALUE .. text:match('^\\(.)', i)
|
|
i = i + 2
|
|
end
|
|
end
|
|
end
|
|
|
|
self:onDecodeError("unclosed string", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local function skip_whitespace(text, start)
|
|
|
|
local _, match_end = text:find("^[ \n\r\t]+", start) -- [http://www.ietf.org/rfc/rfc4627.txt] Section 2
|
|
if match_end then
|
|
return match_end + 1
|
|
else
|
|
return start
|
|
end
|
|
end
|
|
|
|
local grok_one -- assigned later
|
|
|
|
local function grok_object(self, text, start, options)
|
|
|
|
if text:sub(start,start) ~= '{' then
|
|
self:onDecodeError("expected '{'", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local i = skip_whitespace(text, start + 1) -- +1 to skip the '{'
|
|
|
|
local VALUE = self.strictTypes and self:newObject { } or { }
|
|
|
|
if text:sub(i,i) == '}' then
|
|
return VALUE, i + 1
|
|
end
|
|
local text_len = text:len()
|
|
while i <= text_len do
|
|
local key, new_i = grok_string(self, text, i, options)
|
|
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
if text:sub(i, i) ~= ':' then
|
|
self:onDecodeError("expected colon", text, i, options.etc)
|
|
return nil, i -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
i = skip_whitespace(text, i + 1)
|
|
|
|
local new_val, new_i = grok_one(self, text, i, options)
|
|
|
|
VALUE[key] = new_val
|
|
|
|
--
|
|
-- Expect now either '}' to end things, or a ',' to allow us to continue.
|
|
--
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
local c = text:sub(i,i)
|
|
|
|
if c == '}' then
|
|
return VALUE, i + 1
|
|
end
|
|
|
|
if text:sub(i, i) ~= ',' then
|
|
self:onDecodeError("expected comma or '}'", text, i, options.etc)
|
|
return nil, i -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
i = skip_whitespace(text, i + 1)
|
|
end
|
|
|
|
self:onDecodeError("unclosed '{'", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local function grok_array(self, text, start, options)
|
|
if text:sub(start,start) ~= '[' then
|
|
self:onDecodeError("expected '['", text, start, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
local i = skip_whitespace(text, start + 1) -- +1 to skip the '['
|
|
local VALUE = self.strictTypes and self:newArray { } or { }
|
|
if text:sub(i,i) == ']' then
|
|
return VALUE, i + 1
|
|
end
|
|
|
|
local VALUE_INDEX = 1
|
|
|
|
local text_len = text:len()
|
|
while i <= text_len do
|
|
local val, new_i = grok_one(self, text, i, options)
|
|
|
|
-- can't table.insert(VALUE, val) here because it's a no-op if val is nil
|
|
VALUE[VALUE_INDEX] = val
|
|
VALUE_INDEX = VALUE_INDEX + 1
|
|
|
|
i = skip_whitespace(text, new_i)
|
|
|
|
--
|
|
-- Expect now either ']' to end things, or a ',' to allow us to continue.
|
|
--
|
|
local c = text:sub(i,i)
|
|
if c == ']' then
|
|
return VALUE, i + 1
|
|
end
|
|
if text:sub(i, i) ~= ',' then
|
|
self:onDecodeError("expected comma or ']'", text, i, options.etc)
|
|
return nil, i -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
i = skip_whitespace(text, i + 1)
|
|
end
|
|
self:onDecodeError("unclosed '['", text, start, options.etc)
|
|
return nil, i -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
|
|
grok_one = function(self, text, start, options)
|
|
-- Skip any whitespace
|
|
start = skip_whitespace(text, start)
|
|
|
|
if start > text:len() then
|
|
self:onDecodeError("unexpected end of string", text, nil, options.etc)
|
|
return nil, start -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
if text:find('^"', start) then
|
|
return grok_string(self, text, start, options.etc)
|
|
|
|
elseif text:find('^[-0123456789 ]', start) then
|
|
return grok_number(self, text, start, options)
|
|
|
|
elseif text:find('^%{', start) then
|
|
return grok_object(self, text, start, options)
|
|
|
|
elseif text:find('^%[', start) then
|
|
return grok_array(self, text, start, options)
|
|
|
|
elseif text:find('^true', start) then
|
|
return true, start + 4
|
|
|
|
elseif text:find('^false', start) then
|
|
return false, start + 5
|
|
|
|
elseif text:find('^null', start) then
|
|
return options.null, start + 4
|
|
|
|
else
|
|
self:onDecodeError("can't parse JSON", text, start, options.etc)
|
|
return nil, 1 -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
end
|
|
|
|
function OBJDEF:decode(text, etc, options)
|
|
--
|
|
-- If the user didn't pass in a table of decode options, make an empty one.
|
|
--
|
|
if type(options) ~= 'table' then
|
|
options = {}
|
|
end
|
|
|
|
--
|
|
-- If they passed in an 'etc' argument, stuff it into the options.
|
|
-- (If not, any 'etc' field in the options they passed in remains to be used)
|
|
--
|
|
if etc ~= nil then
|
|
options.etc = etc
|
|
end
|
|
|
|
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
local error_message = "JSON:decode must be called in method format"
|
|
OBJDEF:onDecodeError(error_message, nil, nil, options.etc)
|
|
return nil, error_message -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
if text == nil then
|
|
local error_message = "nil passed to JSON:decode()"
|
|
self:onDecodeOfNilError(error_message, nil, nil, options.etc)
|
|
return nil, error_message -- in case the error method doesn't abort, return something sensible
|
|
|
|
elseif type(text) ~= 'string' then
|
|
local error_message = "expected string argument to JSON:decode()"
|
|
self:onDecodeError(string.format("%s, got %s", error_message, type(text)), nil, nil, options.etc)
|
|
return nil, error_message -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
if text:match('^%s*$') then
|
|
-- an empty string is nothing, but not an error
|
|
return nil
|
|
end
|
|
|
|
if text:match('^%s*<') then
|
|
-- Can't be JSON... we'll assume it's HTML
|
|
local error_message = "HTML passed to JSON:decode()"
|
|
self:onDecodeOfHTMLError(error_message, text, nil, options.etc)
|
|
return nil, error_message -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
--
|
|
-- Ensure that it's not UTF-32 or UTF-16.
|
|
-- Those are perfectly valid encodings for JSON (as per RFC 4627 section 3),
|
|
-- but this package can't handle them.
|
|
--
|
|
if text:sub(1,1):byte() == 0 or (text:len() >= 2 and text:sub(2,2):byte() == 0) then
|
|
local error_message = "JSON package groks only UTF-8, sorry"
|
|
self:onDecodeError(error_message, text, nil, options.etc)
|
|
return nil, error_message -- in case the error method doesn't abort, return something sensible
|
|
end
|
|
|
|
--
|
|
-- apply global options
|
|
--
|
|
if options.decodeNumbersAsObjects == nil then
|
|
options.decodeNumbersAsObjects = self.decodeNumbersAsObjects
|
|
end
|
|
if options.decodeIntegerObjectificationLength == nil then
|
|
options.decodeIntegerObjectificationLength = self.decodeIntegerObjectificationLength
|
|
end
|
|
if options.decodeDecimalObjectificationLength == nil then
|
|
options.decodeDecimalObjectificationLength = self.decodeDecimalObjectificationLength
|
|
end
|
|
if options.decodeIntegerStringificationLength == nil then
|
|
options.decodeIntegerStringificationLength = self.decodeIntegerStringificationLength
|
|
end
|
|
if options.decodeDecimalStringificationLength == nil then
|
|
options.decodeDecimalStringificationLength = self.decodeDecimalStringificationLength
|
|
end
|
|
|
|
|
|
--
|
|
-- Finally, go parse it
|
|
--
|
|
local success, value, next_i = pcall(grok_one, self, text, 1, options)
|
|
|
|
if success then
|
|
|
|
local error_message = nil
|
|
if next_i ~= #text + 1 then
|
|
-- something's left over after we parsed the first thing.... whitespace is allowed.
|
|
next_i = skip_whitespace(text, next_i)
|
|
|
|
-- if we have something left over now, it's trailing garbage
|
|
if next_i ~= #text + 1 then
|
|
value, error_message = self:onTrailingGarbage(text, next_i, value, options.etc)
|
|
end
|
|
end
|
|
return value, error_message
|
|
|
|
else
|
|
|
|
-- If JSON:onDecodeError() didn't abort out of the pcall, we'll have received
|
|
-- the error message here as "value", so pass it along as an assert.
|
|
local error_message = value
|
|
if self.assert then
|
|
self.assert(false, error_message)
|
|
else
|
|
assert(false, error_message)
|
|
end
|
|
-- ...and if we're still here (because the assert didn't throw an error),
|
|
-- return a nil and throw the error message on as a second arg
|
|
return nil, error_message
|
|
|
|
end
|
|
end
|
|
|
|
local function backslash_replacement_function(c)
|
|
if c == "\n" then
|
|
return "\\n"
|
|
elseif c == "\r" then
|
|
return "\\r"
|
|
elseif c == "\t" then
|
|
return "\\t"
|
|
elseif c == "\b" then
|
|
return "\\b"
|
|
elseif c == "\f" then
|
|
return "\\f"
|
|
elseif c == '"' then
|
|
return '\\"'
|
|
elseif c == '\\' then
|
|
return '\\\\'
|
|
else
|
|
return string.format("\\u%04x", c:byte())
|
|
end
|
|
end
|
|
|
|
local chars_to_be_escaped_in_JSON_string
|
|
= '['
|
|
.. '"' -- class sub-pattern to match a double quote
|
|
.. '%\\' -- class sub-pattern to match a backslash
|
|
.. '%z' -- class sub-pattern to match a null
|
|
.. '\001' .. '-' .. '\031' -- class sub-pattern to match control characters
|
|
.. ']'
|
|
|
|
|
|
local LINE_SEPARATOR_as_utf8 = unicode_codepoint_as_utf8(0x2028)
|
|
local PARAGRAPH_SEPARATOR_as_utf8 = unicode_codepoint_as_utf8(0x2029)
|
|
local function json_string_literal(value, options)
|
|
local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function)
|
|
if options.stringsAreUtf8 then
|
|
--
|
|
-- This feels really ugly to just look into a string for the sequence of bytes that we know to be a particular utf8 character,
|
|
-- but utf8 was designed purposefully to make this kind of thing possible. Still, feels dirty.
|
|
-- I'd rather decode the byte stream into a character stream, but it's not technically needed so
|
|
-- not technically worth it.
|
|
--
|
|
newval = newval:gsub(LINE_SEPARATOR_as_utf8, '\\u2028'):gsub(PARAGRAPH_SEPARATOR_as_utf8,'\\u2029')
|
|
end
|
|
return '"' .. newval .. '"'
|
|
end
|
|
|
|
local function object_or_array(self, T, etc)
|
|
--
|
|
-- We need to inspect all the keys... if there are any strings, we'll convert to a JSON
|
|
-- object. If there are only numbers, it's a JSON array.
|
|
--
|
|
-- If we'll be converting to a JSON object, we'll want to sort the keys so that the
|
|
-- end result is deterministic.
|
|
--
|
|
local string_keys = { }
|
|
local number_keys = { }
|
|
local number_keys_must_be_strings = false
|
|
local maximum_number_key
|
|
|
|
for key in pairs(T) do
|
|
if type(key) == 'string' then
|
|
table.insert(string_keys, key)
|
|
elseif type(key) == 'number' then
|
|
table.insert(number_keys, key)
|
|
if key <= 0 or key >= math.huge then
|
|
number_keys_must_be_strings = true
|
|
elseif not maximum_number_key or key > maximum_number_key then
|
|
maximum_number_key = key
|
|
end
|
|
elseif type(key) == 'boolean' then
|
|
table.insert(string_keys, tostring(key))
|
|
else
|
|
self:onEncodeError("can't encode table with a key of type " .. type(key), etc)
|
|
end
|
|
end
|
|
|
|
if #string_keys == 0 and not number_keys_must_be_strings then
|
|
--
|
|
-- An empty table, or a numeric-only array
|
|
--
|
|
if #number_keys > 0 then
|
|
return nil, maximum_number_key -- an array
|
|
elseif tostring(T) == "JSON array" then
|
|
return nil
|
|
elseif tostring(T) == "JSON object" then
|
|
return { }
|
|
else
|
|
-- have to guess, so we'll pick array, since empty arrays are likely more common than empty objects
|
|
return nil
|
|
end
|
|
end
|
|
|
|
table.sort(string_keys)
|
|
|
|
local map
|
|
if #number_keys > 0 then
|
|
--
|
|
-- If we're here then we have either mixed string/number keys, or numbers inappropriate for a JSON array
|
|
-- It's not ideal, but we'll turn the numbers into strings so that we can at least create a JSON object.
|
|
--
|
|
|
|
if self.noKeyConversion then
|
|
self:onEncodeError("a table with both numeric and string keys could be an object or array; aborting", etc)
|
|
end
|
|
|
|
--
|
|
-- Have to make a shallow copy of the source table so we can remap the numeric keys to be strings
|
|
--
|
|
map = { }
|
|
for key, val in pairs(T) do
|
|
map[key] = val
|
|
end
|
|
|
|
table.sort(number_keys)
|
|
|
|
--
|
|
-- Throw numeric keys in there as strings
|
|
--
|
|
for _, number_key in ipairs(number_keys) do
|
|
local string_key = tostring(number_key)
|
|
if map[string_key] == nil then
|
|
table.insert(string_keys , string_key)
|
|
map[string_key] = T[number_key]
|
|
else
|
|
self:onEncodeError("conflict converting table with mixed-type keys into a JSON object: key " .. number_key .. " exists both as a string and a number.", etc)
|
|
end
|
|
end
|
|
end
|
|
|
|
return string_keys, nil, map
|
|
end
|
|
|
|
--
|
|
-- Encode
|
|
--
|
|
-- 'options' is nil, or a table with possible keys:
|
|
--
|
|
-- pretty -- If true, return a pretty-printed version.
|
|
--
|
|
-- indent -- A string (usually of spaces) used to indent each nested level.
|
|
--
|
|
-- align_keys -- If true, align all the keys when formatting a table. The result is uglier than one might at first imagine.
|
|
-- Results are undefined if 'align_keys' is true but 'pretty' is not.
|
|
--
|
|
-- array_newline -- If true, array elements are formatted each to their own line. The default is to all fall inline.
|
|
-- Results are undefined if 'array_newline' is true but 'pretty' is not.
|
|
--
|
|
-- null -- If this exists with a string value, table elements with this value are output as JSON null.
|
|
--
|
|
-- stringsAreUtf8 -- If true, consider Lua strings not as a sequence of bytes, but as a sequence of UTF-8 characters.
|
|
-- (Currently, the only practical effect of setting this option is that Unicode LINE and PARAGRAPH
|
|
-- separators, if found in a string, are encoded with a JSON escape instead of as raw UTF-8.
|
|
-- The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
|
|
-- to also be valid Java.)
|
|
--
|
|
--
|
|
local function encode_value(self, value, parents, etc, options, indent, for_key)
|
|
|
|
--
|
|
-- keys in a JSON object can never be null, so we don't even consider options.null when converting a key value
|
|
--
|
|
if value == nil or (not for_key and options and options.null and value == options.null) then
|
|
return 'null'
|
|
|
|
elseif type(value) == 'string' then
|
|
return json_string_literal(value, options)
|
|
|
|
elseif type(value) == 'number' then
|
|
if value ~= value then
|
|
--
|
|
-- NaN (Not a Number).
|
|
-- JSON has no NaN, so we have to fudge the best we can. This should really be a package option.
|
|
--
|
|
return "null"
|
|
elseif value >= math.huge then
|
|
--
|
|
-- Positive infinity. JSON has no INF, so we have to fudge the best we can. This should
|
|
-- really be a package option. Note: at least with some implementations, positive infinity
|
|
-- is both ">= math.huge" and "<= -math.huge", which makes no sense but that's how it is.
|
|
-- Negative infinity is properly "<= -math.huge". So, we must be sure to check the ">="
|
|
-- case first.
|
|
--
|
|
return "1e+9999"
|
|
elseif value <= -math.huge then
|
|
--
|
|
-- Negative infinity.
|
|
-- JSON has no INF, so we have to fudge the best we can. This should really be a package option.
|
|
--
|
|
return "-1e+9999"
|
|
else
|
|
return tostring(value)
|
|
end
|
|
|
|
elseif type(value) == 'boolean' then
|
|
return tostring(value)
|
|
|
|
elseif type(value) ~= 'table' then
|
|
|
|
if self.unsupportedTypeEncoder then
|
|
local user_value, user_error = self:unsupportedTypeEncoder(value, parents, etc, options, indent, for_key)
|
|
-- If the user's handler returns a string, use that. If it returns nil plus an error message, bail with that.
|
|
-- If only nil returned, fall through to the default error handler.
|
|
if type(user_value) == 'string' then
|
|
return user_value
|
|
elseif user_value ~= nil then
|
|
self:onEncodeError("unsupportedTypeEncoder method returned a " .. type(user_value), etc)
|
|
elseif user_error then
|
|
self:onEncodeError(tostring(user_error), etc)
|
|
end
|
|
end
|
|
|
|
self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc)
|
|
|
|
elseif getmetatable(value) == isNumber then
|
|
return tostring(value)
|
|
else
|
|
--
|
|
-- A table to be converted to either a JSON object or array.
|
|
--
|
|
local T = value
|
|
|
|
if type(options) ~= 'table' then
|
|
options = {}
|
|
end
|
|
if type(indent) ~= 'string' then
|
|
indent = ""
|
|
end
|
|
|
|
if parents[T] then
|
|
self:onEncodeError("table " .. tostring(T) .. " is a child of itself", etc)
|
|
else
|
|
parents[T] = true
|
|
end
|
|
|
|
local result_value
|
|
|
|
local object_keys, maximum_number_key, map = object_or_array(self, T, etc)
|
|
if maximum_number_key then
|
|
--
|
|
-- An array...
|
|
--
|
|
local key_indent
|
|
if options.array_newline then
|
|
key_indent = indent .. tostring(options.indent or "")
|
|
else
|
|
key_indent = indent
|
|
end
|
|
|
|
local ITEMS = { }
|
|
for i = 1, maximum_number_key do
|
|
table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, key_indent))
|
|
end
|
|
|
|
if options.array_newline then
|
|
result_value = "[\n" .. key_indent .. table.concat(ITEMS, ",\n" .. key_indent) .. "\n" .. indent .. "]"
|
|
elseif options.pretty then
|
|
result_value = "[ " .. table.concat(ITEMS, ", ") .. " ]"
|
|
else
|
|
result_value = "[" .. table.concat(ITEMS, ",") .. "]"
|
|
end
|
|
|
|
elseif object_keys then
|
|
--
|
|
-- An object
|
|
--
|
|
local TT = map or T
|
|
|
|
if options.pretty then
|
|
|
|
local KEYS = { }
|
|
local max_key_length = 0
|
|
for _, key in ipairs(object_keys) do
|
|
local encoded = encode_value(self, tostring(key), parents, etc, options, indent, true)
|
|
if options.align_keys then
|
|
max_key_length = math.max(max_key_length, #encoded)
|
|
end
|
|
table.insert(KEYS, encoded)
|
|
end
|
|
local key_indent = indent .. tostring(options.indent or "")
|
|
local subtable_indent = key_indent .. string.rep(" ", max_key_length) .. (options.align_keys and " " or "")
|
|
local FORMAT = "%s%" .. string.format("%d", max_key_length) .. "s: %s"
|
|
|
|
local COMBINED_PARTS = { }
|
|
for i, key in ipairs(object_keys) do
|
|
local encoded_val = encode_value(self, TT[key], parents, etc, options, subtable_indent)
|
|
table.insert(COMBINED_PARTS, string.format(FORMAT, key_indent, KEYS[i], encoded_val))
|
|
end
|
|
result_value = "{\n" .. table.concat(COMBINED_PARTS, ",\n") .. "\n" .. indent .. "}"
|
|
|
|
else
|
|
|
|
local PARTS = { }
|
|
for _, key in ipairs(object_keys) do
|
|
local encoded_val = encode_value(self, TT[key], parents, etc, options, indent)
|
|
local encoded_key = encode_value(self, tostring(key), parents, etc, options, indent, true)
|
|
table.insert(PARTS, string.format("%s:%s", encoded_key, encoded_val))
|
|
end
|
|
result_value = "{" .. table.concat(PARTS, ",") .. "}"
|
|
|
|
end
|
|
else
|
|
--
|
|
-- An empty array/object... we'll treat it as an array, though it should really be an option
|
|
--
|
|
result_value = "[]"
|
|
end
|
|
|
|
parents[T] = false
|
|
return result_value
|
|
end
|
|
end
|
|
|
|
local function top_level_encode(self, value, etc, options)
|
|
local val = encode_value(self, value, {}, etc, options)
|
|
if val == nil then
|
|
--PRIVATE("may need to revert to the previous public verison if I can't figure out what the guy wanted")
|
|
return val
|
|
else
|
|
return val
|
|
end
|
|
end
|
|
|
|
function OBJDEF:encode(value, etc, options)
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
OBJDEF:onEncodeError("JSON:encode must be called in method format", etc)
|
|
end
|
|
|
|
--
|
|
-- If the user didn't pass in a table of decode options, make an empty one.
|
|
--
|
|
if type(options) ~= 'table' then
|
|
options = {}
|
|
end
|
|
|
|
return top_level_encode(self, value, etc, options)
|
|
end
|
|
|
|
function OBJDEF:encode_pretty(value, etc, options)
|
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then
|
|
OBJDEF:onEncodeError("JSON:encode_pretty must be called in method format", etc)
|
|
end
|
|
|
|
--
|
|
-- If the user didn't pass in a table of decode options, use the default pretty ones
|
|
--
|
|
if type(options) ~= 'table' then
|
|
options = default_pretty_options
|
|
end
|
|
|
|
return top_level_encode(self, value, etc, options)
|
|
end
|
|
|
|
function OBJDEF.__tostring()
|
|
return "JSON encode/decode package"
|
|
end
|
|
|
|
OBJDEF.__index = OBJDEF
|
|
|
|
function OBJDEF:new(args)
|
|
local new = { }
|
|
|
|
if args then
|
|
for key, val in pairs(args) do
|
|
new[key] = val
|
|
end
|
|
end
|
|
|
|
return setmetatable(new, OBJDEF)
|
|
end
|
|
|
|
return OBJDEF:new()
|
|
|
|
--
|
|
-- Version history:
|
|
--
|
|
-- 20170927.26 Use option.null in decoding as well. Thanks to Max Sindwani for the bump, and sorry to Oliver Hitz
|
|
-- whose first mention of it four years ago was completely missed by me.
|
|
--
|
|
-- 20170823.25 Added support for JSON:unsupportedTypeEncoder().
|
|
-- Thanks to Chronos Phaenon Eosphoros (https://github.com/cpeosphoros) for the idea.
|
|
--
|
|
-- 20170819.24 Added support for boolean keys in tables.
|
|
--
|
|
-- 20170416.23 Added the "array_newline" formatting option suggested by yurenchen (http://www.yurenchen.com/)
|
|
--
|
|
-- 20161128.22 Added:
|
|
-- JSON:isString()
|
|
-- JSON:isNumber()
|
|
-- JSON:decodeIntegerObjectificationLength
|
|
-- JSON:decodeDecimalObjectificationLength
|
|
--
|
|
-- 20161109.21 Oops, had a small boo-boo in the previous update.
|
|
--
|
|
-- 20161103.20 Used to silently ignore trailing garbage when decoding. Now fails via JSON:onTrailingGarbage()
|
|
-- http://seriot.ch/parsing_json.php
|
|
--
|
|
-- Built-in error message about "expected comma or ']'" had mistakenly referred to '['
|
|
--
|
|
-- Updated the built-in error reporting to refer to bytes rather than characters.
|
|
--
|
|
-- The decode() method no longer assumes that error handlers abort.
|
|
--
|
|
-- Made the VERSION string a string instead of a number
|
|
--
|
|
|
|
-- 20160916.19 Fixed the isNumber.__index assignment (thanks to Jack Taylor)
|
|
--
|
|
-- 20160730.18 Added JSON:forceString() and JSON:forceNumber()
|
|
--
|
|
-- 20160728.17 Added concatenation to the metatable for JSON:asNumber()
|
|
--
|
|
-- 20160709.16 Could crash if not passed an options table (thanks jarno heikkinen <jarnoh@capturemonkey.com>).
|
|
--
|
|
-- Made JSON:asNumber() a bit more resilient to being passed the results of itself.
|
|
--
|
|
-- 20160526.15 Added the ability to easily encode null values in JSON, via the new "null" encoding option.
|
|
-- (Thanks to Adam B for bringing up the issue.)
|
|
--
|
|
-- Added some support for very large numbers and precise floats via
|
|
-- JSON.decodeNumbersAsObjects
|
|
-- JSON.decodeIntegerStringificationLength
|
|
-- JSON.decodeDecimalStringificationLength
|
|
--
|
|
-- Added the "stringsAreUtf8" encoding option. (Hat tip to http://lua-users.org/wiki/JsonModules )
|
|
--
|
|
-- 20141223.14 The encode_pretty() routine produced fine results for small datasets, but isn't really
|
|
-- appropriate for anything large, so with help from Alex Aulbach I've made the encode routines
|
|
-- more flexible, and changed the default encode_pretty() to be more generally useful.
|
|
--
|
|
-- Added a third 'options' argument to the encode() and encode_pretty() routines, to control
|
|
-- how the encoding takes place.
|
|
--
|
|
-- Updated docs to add assert() call to the loadfile() line, just as good practice so that
|
|
-- if there is a problem loading JSON.lua, the appropriate error message will percolate up.
|
|
--
|
|
-- 20140920.13 Put back (in a way that doesn't cause warnings about unused variables) the author string,
|
|
-- so that the source of the package, and its version number, are visible in compiled copies.
|
|
--
|
|
-- 20140911.12 Minor lua cleanup.
|
|
-- Fixed internal reference to 'JSON.noKeyConversion' to reference 'self' instead of 'JSON'.
|
|
-- (Thanks to SmugMug's David Parry for these.)
|
|
--
|
|
-- 20140418.11 JSON nulls embedded within an array were being ignored, such that
|
|
-- ["1",null,null,null,null,null,"seven"],
|
|
-- would return
|
|
-- {1,"seven"}
|
|
-- It's now fixed to properly return
|
|
-- {1, nil, nil, nil, nil, nil, "seven"}
|
|
-- Thanks to "haddock" for catching the error.
|
|
--
|
|
-- 20140116.10 The user's JSON.assert() wasn't always being used. Thanks to "blue" for the heads up.
|
|
--
|
|
-- 20131118.9 Update for Lua 5.3... it seems that tostring(2/1) produces "2.0" instead of "2",
|
|
-- and this caused some problems.
|
|
--
|
|
-- 20131031.8 Unified the code for encode() and encode_pretty(); they had been stupidly separate,
|
|
-- and had of course diverged (encode_pretty didn't get the fixes that encode got, so
|
|
-- sometimes produced incorrect results; thanks to Mattie for the heads up).
|
|
--
|
|
-- Handle encoding tables with non-positive numeric keys (unlikely, but possible).
|
|
--
|
|
-- If a table has both numeric and string keys, or its numeric keys are inappropriate
|
|
-- (such as being non-positive or infinite), the numeric keys are turned into
|
|
-- string keys appropriate for a JSON object. So, as before,
|
|
-- JSON:encode({ "one", "two", "three" })
|
|
-- produces the array
|
|
-- ["one","two","three"]
|
|
-- but now something with mixed key types like
|
|
-- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" }))
|
|
-- instead of throwing an error produces an object:
|
|
-- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"}
|
|
--
|
|
-- To maintain the prior throw-an-error semantics, set
|
|
-- JSON.noKeyConversion = true
|
|
--
|
|
-- 20131004.7 Release under a Creative Commons CC-BY license, which I should have done from day one, sorry.
|
|
--
|
|
-- 20130120.6 Comment update: added a link to the specific page on my blog where this code can
|
|
-- be found, so that folks who come across the code outside of my blog can find updates
|
|
-- more easily.
|
|
--
|
|
-- 20111207.5 Added support for the 'etc' arguments, for better error reporting.
|
|
--
|
|
-- 20110731.4 More feedback from David Kolf on how to make the tests for Nan/Infinity system independent.
|
|
--
|
|
-- 20110730.3 Incorporated feedback from David Kolf at http://lua-users.org/wiki/JsonModules:
|
|
--
|
|
-- * When encoding lua for JSON, Sparse numeric arrays are now handled by
|
|
-- spitting out full arrays, such that
|
|
-- JSON:encode({"one", "two", [10] = "ten"})
|
|
-- returns
|
|
-- ["one","two",null,null,null,null,null,null,null,"ten"]
|
|
--
|
|
-- In 20100810.2 and earlier, only up to the first non-null value would have been retained.
|
|
--
|
|
-- * When encoding lua for JSON, numeric value NaN gets spit out as null, and infinity as "1+e9999".
|
|
-- Version 20100810.2 and earlier created invalid JSON in both cases.
|
|
--
|
|
-- * Unicode surrogate pairs are now detected when decoding JSON.
|
|
--
|
|
-- 20100810.2 added some checking to ensure that an invalid Unicode character couldn't leak in to the UTF-8 encoding
|
|
--
|
|
-- 20100731.1 initial public release
|
|
--
|