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-- -*- 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 2010-2013 Jeffrey Friedl |
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-- http://regex.info/blog/ |
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-- |
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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 the copyright notice and |
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-- web-page links above are maintained. Enjoy. |
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-- |
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local VERSION = 20140116.10 -- version history at end of file |
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local OBJDEF = { VERSION = VERSION } |
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-- |
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-- Simple JSON encoding and decoding in pure Lua. |
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-- http://www.json.org/ |
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-- |
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-- |
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-- JSON = (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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-- DECODING |
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-- |
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-- JSON = (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, "etc", which is not used |
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-- during encoding or decoding, but upon error is passed along to error handlers. It can be of any |
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-- type (including nil). |
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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 parsed and the byte count |
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-- where the problem was discovered. You can replace the default JSON:onDecodeError() with your |
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-- own function. |
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-- |
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-- The default onDecodeError() merely augments the message with data about the text and the |
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-- location if known (and if a second 'etc' argument had been provided to decode(), its value is |
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-- tacked onto the message as well), and then calls JSON.assert(), which itself defaults to Lua's |
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-- built-in 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 fourth 'etc' argument allows stronger coordination between decoding and error |
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-- reporting, especially when you provide your own error-handling routines. Continuing with the |
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-- the Adobe Lightroom 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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-- |
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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, it's not normally |
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-- possible to tell which a JSON type a particular Lua table was derived from, or guarantee |
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-- decode-encode 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 = (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 JSON array is marked via Lua |
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-- metatable, so that when re-encoded with 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 tables that have a |
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-- metatable set, for example, Lightroom API calls.) |
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-- |
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-- |
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-- ENCODING |
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-- |
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-- JSON = (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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-- 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. |
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-- |
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-- If the Lua table contains both string and numeric keys, it fits neither JSON's |
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-- idea of an object, nor its idea of an array. To get around this, when any string |
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-- key exists (or when non-positive numeric keys exist), numeric keys are converted |
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-- to 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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-- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT |
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-- |
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-- assert |
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-- onDecodeError |
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-- onDecodeOfNilError |
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-- onDecodeOfHTMLError |
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-- onEncodeError |
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-- |
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-- If you want to create a separate Lua JSON object with its own error handlers, |
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-- you can reload JSON.lua or use the :new() method. |
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-- |
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--------------------------------------------------------------------------- |
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local author = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json), version " .. tostring(VERSION) .. " ]-" |
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local isArray = { __tostring = function() return "JSON array" end } isArray.__index = isArray |
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local isObject = { __tostring = function() return "JSON object" end } isObject.__index = isObject |
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function OBJDEF:newArray(tbl) |
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return setmetatable(tbl or {}, isArray) |
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end |
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function OBJDEF:newObject(tbl) |
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return setmetatable(tbl or {}, isObject) |
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end |
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local function unicode_codepoint_as_utf8(codepoint) |
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-- |
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-- codepoint is a number |
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-- |
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if codepoint <= 127 then |
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return string.char(codepoint) |
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elseif codepoint <= 2047 then |
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-- |
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-- 110yyyxx 10xxxxxx <-- useful notation from http://en.wikipedia.org/wiki/Utf8 |
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-- |
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local highpart = math.floor(codepoint / 0x40) |
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local lowpart = codepoint - (0x40 * highpart) |
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return string.char(0xC0 + highpart, |
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0x80 + lowpart) |
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elseif codepoint <= 65535 then |
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-- |
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-- 1110yyyy 10yyyyxx 10xxxxxx |
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-- |
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local highpart = math.floor(codepoint / 0x1000) |
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local remainder = codepoint - 0x1000 * highpart |
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local midpart = math.floor(remainder / 0x40) |
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local lowpart = remainder - 0x40 * midpart |
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highpart = 0xE0 + highpart |
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midpart = 0x80 + midpart |
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lowpart = 0x80 + lowpart |
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-- |
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-- Check for an invalid character (thanks Andy R. at Adobe). |
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-- See table 3.7, page 93, in http://www.unicode.org/versions/Unicode5.2.0/ch03.pdf#G28070 |
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-- |
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if ( highpart == 0xE0 and midpart < 0xA0 ) or |
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( highpart == 0xED and midpart > 0x9F ) or |
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( highpart == 0xF0 and midpart < 0x90 ) or |
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( highpart == 0xF4 and midpart > 0x8F ) |
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then |
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return "?" |
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else |
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return string.char(highpart, |
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midpart, |
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lowpart) |
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end |
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else |
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-- |
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-- 11110zzz 10zzyyyy 10yyyyxx 10xxxxxx |
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-- |
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local highpart = math.floor(codepoint / 0x40000) |
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local remainder = codepoint - 0x40000 * highpart |
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local midA = math.floor(remainder / 0x1000) |
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remainder = remainder - 0x1000 * midA |
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local midB = math.floor(remainder / 0x40) |
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local lowpart = remainder - 0x40 * midB |
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return string.char(0xF0 + highpart, |
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0x80 + midA, |
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0x80 + midB, |
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0x80 + lowpart) |
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end |
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end |
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function OBJDEF:onDecodeError(message, text, location, etc) |
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if text then |
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if location then |
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message = string.format("%s at char %d of: %s", message, location, text) |
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else |
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message = string.format("%s: %s", message, text) |
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end |
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end |
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if etc ~= nil then |
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message = message .. " (" .. OBJDEF:encode(etc) .. ")" |
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end |
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if self.assert then |
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self.assert(false, message) |
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else |
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assert(false, message) |
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end |
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end |
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OBJDEF.onDecodeOfNilError = OBJDEF.onDecodeError |
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OBJDEF.onDecodeOfHTMLError = OBJDEF.onDecodeError |
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function OBJDEF:onEncodeError(message, etc) |
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if etc ~= nil then |
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message = message .. " (" .. OBJDEF:encode(etc) .. ")" |
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end |
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if self.assert then |
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self.assert(false, message) |
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else |
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assert(false, message) |
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end |
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end |
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local function grok_number(self, text, start, etc) |
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-- |
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-- Grab the integer part |
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-- |
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local integer_part = text:match('^-?[1-9]%d*', start) |
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or text:match("^-?0", start) |
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if not integer_part then |
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self:onDecodeError("expected number", text, start, etc) |
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end |
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local i = start + integer_part:len() |
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-- |
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-- Grab an optional decimal part |
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-- |
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local decimal_part = text:match('^%.%d+', i) or "" |
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i = i + decimal_part:len() |
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-- |
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-- Grab an optional exponential part |
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-- |
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local exponent_part = text:match('^[eE][-+]?%d+', i) or "" |
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i = i + exponent_part:len() |
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local full_number_text = integer_part .. decimal_part .. exponent_part |
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local as_number = tonumber(full_number_text) |
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if not as_number then |
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self:onDecodeError("bad number", text, start, etc) |
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end |
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return as_number, i |
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end |
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local function grok_string(self, text, start, etc) |
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if text:sub(start,start) ~= '"' then |
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self:onDecodeError("expected string's opening quote", text, start, etc) |
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end |
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local i = start + 1 -- +1 to bypass the initial quote |
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local text_len = text:len() |
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local VALUE = "" |
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while i <= text_len do |
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local c = text:sub(i,i) |
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if c == '"' then |
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return VALUE, i + 1 |
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end |
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if c ~= '\\' then |
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VALUE = VALUE .. c |
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i = i + 1 |
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elseif text:match('^\\b', i) then |
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VALUE = VALUE .. "\b" |
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i = i + 2 |
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elseif text:match('^\\f', i) then |
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VALUE = VALUE .. "\f" |
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i = i + 2 |
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elseif text:match('^\\n', i) then |
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VALUE = VALUE .. "\n" |
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i = i + 2 |
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elseif text:match('^\\r', i) then |
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VALUE = VALUE .. "\r" |
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i = i + 2 |
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elseif text:match('^\\t', i) then |
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VALUE = VALUE .. "\t" |
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i = i + 2 |
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else |
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local hex = text:match('^\\u([0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i) |
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if hex then |
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i = i + 6 -- bypass what we just read |
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-- We have a Unicode codepoint. It could be standalone, or if in the proper range and |
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-- followed by another in a specific range, it'll be a two-code surrogate pair. |
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local codepoint = tonumber(hex, 16) |
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if codepoint >= 0xD800 and codepoint <= 0xDBFF then |
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-- it's a hi surrogate... see whether we have a following low |
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local lo_surrogate = text:match('^\\u([dD][cdefCDEF][0123456789aAbBcCdDeEfF][0123456789aAbBcCdDeEfF])', i) |
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if lo_surrogate then |
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i = i + 6 -- bypass the low surrogate we just read |
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codepoint = 0x2400 + (codepoint - 0xD800) * 0x400 + tonumber(lo_surrogate, 16) |
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else |
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-- not a proper low, so we'll just leave the first codepoint as is and spit it out. |
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end |
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end |
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VALUE = VALUE .. unicode_codepoint_as_utf8(codepoint) |
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else |
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-- just pass through what's escaped |
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VALUE = VALUE .. text:match('^\\(.)', i) |
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i = i + 2 |
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end |
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end |
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end |
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self:onDecodeError("unclosed string", text, start, etc) |
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end |
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local function skip_whitespace(text, start) |
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local match_start, match_end = text:find("^[ \n\r\t]+", start) -- [http://www.ietf.org/rfc/rfc4627.txt] Section 2 |
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if match_end then |
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return match_end + 1 |
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else |
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return start |
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end |
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end |
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local grok_one -- assigned later |
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local function grok_object(self, text, start, etc) |
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if not text:sub(start,start) == '{' then |
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self:onDecodeError("expected '{'", text, start, etc) |
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end |
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local i = skip_whitespace(text, start + 1) -- +1 to skip the '{' |
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local VALUE = self.strictTypes and self:newObject { } or { } |
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if text:sub(i,i) == '}' then |
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return VALUE, i + 1 |
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end |
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local text_len = text:len() |
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while i <= text_len do |
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local key, new_i = grok_string(self, text, i, etc) |
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i = skip_whitespace(text, new_i) |
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if text:sub(i, i) ~= ':' then |
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self:onDecodeError("expected colon", text, i, etc) |
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end |
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i = skip_whitespace(text, i + 1) |
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local val, new_i = grok_one(self, text, i) |
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VALUE[key] = val |
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-- |
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-- Expect now either '}' to end things, or a ',' to allow us to continue. |
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-- |
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i = skip_whitespace(text, new_i) |
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local c = text:sub(i,i) |
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if c == '}' then |
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return VALUE, i + 1 |
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end |
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if text:sub(i, i) ~= ',' then |
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self:onDecodeError("expected comma or '}'", text, i, etc) |
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end |
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i = skip_whitespace(text, i + 1) |
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end |
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self:onDecodeError("unclosed '{'", text, start, etc) |
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end |
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local function grok_array(self, text, start, etc) |
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if not text:sub(start,start) == '[' then |
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self:onDecodeError("expected '['", text, start, etc) |
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end |
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local i = skip_whitespace(text, start + 1) -- +1 to skip the '[' |
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local VALUE = self.strictTypes and self:newArray { } or { } |
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if text:sub(i,i) == ']' then |
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return VALUE, i + 1 |
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end |
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local text_len = text:len() |
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while i <= text_len do |
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local val, new_i = grok_one(self, text, i) |
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table.insert(VALUE, val) |
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i = skip_whitespace(text, new_i) |
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-- |
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-- Expect now either ']' to end things, or a ',' to allow us to continue. |
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-- |
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local c = text:sub(i,i) |
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if c == ']' then |
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return VALUE, i + 1 |
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end |
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if text:sub(i, i) ~= ',' then |
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self:onDecodeError("expected comma or '['", text, i, etc) |
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end |
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i = skip_whitespace(text, i + 1) |
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end |
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self:onDecodeError("unclosed '['", text, start, etc) |
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end |
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grok_one = function(self, text, start, etc) |
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-- Skip any whitespace |
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start = skip_whitespace(text, start) |
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if start > text:len() then |
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self:onDecodeError("unexpected end of string", text, nil, etc) |
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end |
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if text:find('^"', start) then |
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return grok_string(self, text, start, etc) |
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elseif text:find('^[-0123456789 ]', start) then |
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return grok_number(self, text, start, etc) |
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elseif text:find('^%{', start) then |
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return grok_object(self, text, start, etc) |
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elseif text:find('^%[', start) then |
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return grok_array(self, text, start, etc) |
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elseif text:find('^true', start) then |
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return true, start + 4 |
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elseif text:find('^false', start) then |
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return false, start + 5 |
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elseif text:find('^null', start) then |
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return nil, start + 4 |
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else |
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self:onDecodeError("can't parse JSON", text, start, etc) |
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end |
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end |
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function OBJDEF:decode(text, etc) |
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if type(self) ~= 'table' or self.__index ~= OBJDEF then |
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OBJDEF:onDecodeError("JSON:decode must be called in method format", nil, nil, etc) |
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end |
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if text == nil then |
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self:onDecodeOfNilError(string.format("nil passed to JSON:decode()"), nil, nil, etc) |
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elseif type(text) ~= 'string' then |
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self:onDecodeError(string.format("expected string argument to JSON:decode(), got %s", type(text)), nil, nil, etc) |
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end |
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if text:match('^%s*$') then |
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return nil |
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end |
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if text:match('^%s*<') then |
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-- Can't be JSON... we'll assume it's HTML |
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self:onDecodeOfHTMLError(string.format("html passed to JSON:decode()"), text, nil, etc) |
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end |
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|
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-- |
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-- Ensure that it's not UTF-32 or UTF-16. |
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-- Those are perfectly valid encodings for JSON (as per RFC 4627 section 3), |
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-- but this package can't handle them. |
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-- |
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if text:sub(1,1):byte() == 0 or (text:len() >= 2 and text:sub(2,2):byte() == 0) then |
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self:onDecodeError("JSON package groks only UTF-8, sorry", text, nil, etc) |
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end |
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local success, value = pcall(grok_one, self, text, 1, etc) |
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if success then |
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return value |
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else |
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-- 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. |
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if self.assert then |
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self.assert(false, value) |
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else |
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assert(false, value) |
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end |
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-- and if we're still here, return a nil and throw the error message on as a second arg |
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return nil, value |
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end |
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end |
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local function backslash_replacement_function(c) |
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if c == "\n" then |
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return "\\n" |
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elseif c == "\r" then |
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return "\\r" |
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elseif c == "\t" then |
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return "\\t" |
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elseif c == "\b" then |
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return "\\b" |
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elseif c == "\f" then |
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return "\\f" |
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elseif c == '"' then |
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return '\\"' |
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elseif c == '\\' then |
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return '\\\\' |
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else |
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return string.format("\\u%04x", c:byte()) |
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end |
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end |
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local chars_to_be_escaped_in_JSON_string |
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= '[' |
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.. '"' -- class sub-pattern to match a double quote |
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.. '%\\' -- 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 function json_string_literal(value) |
|
local newval = value:gsub(chars_to_be_escaped_in_JSON_string, backslash_replacement_function) |
|
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 |
|
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 JSON.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 |
|
-- |
|
local encode_value -- must predeclare because it calls itself |
|
function encode_value(self, value, parents, etc, indent) -- non-nil indent means pretty-printing |
|
|
|
if value == nil then |
|
return 'null' |
|
|
|
elseif type(value) == 'string' then |
|
return json_string_literal(value) |
|
|
|
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 |
|
self:onEncodeError("can't convert " .. type(value) .. " to JSON", etc) |
|
|
|
else |
|
-- |
|
-- A table to be converted to either a JSON object or array. |
|
-- |
|
local T = value |
|
|
|
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 ITEMS = { } |
|
for i = 1, maximum_number_key do |
|
table.insert(ITEMS, encode_value(self, T[i], parents, etc, indent)) |
|
end |
|
|
|
if indent 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 indent then |
|
|
|
local KEYS = { } |
|
local max_key_length = 0 |
|
for _, key in ipairs(object_keys) do |
|
local encoded = encode_value(self, tostring(key), parents, etc, "") |
|
max_key_length = math.max(max_key_length, #encoded) |
|
table.insert(KEYS, encoded) |
|
end |
|
local key_indent = indent .. " " |
|
local subtable_indent = indent .. string.rep(" ", max_key_length + 2 + 4) |
|
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, 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, indent) |
|
local encoded_key = encode_value(self, tostring(key), parents, etc, indent) |
|
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 |
|
|
|
|
|
function OBJDEF:encode(value, etc) |
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then |
|
OBJDEF:onEncodeError("JSON:encode must be called in method format", etc) |
|
end |
|
return encode_value(self, value, {}, etc, nil) |
|
end |
|
|
|
function OBJDEF:encode_pretty(value, etc) |
|
if type(self) ~= 'table' or self.__index ~= OBJDEF then |
|
OBJDEF:onEncodeError("JSON:encode_pretty must be called in method format", etc) |
|
end |
|
return encode_value(self, value, {}, etc, "") |
|
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: |
|
-- |
|
-- 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 |
|
-- |
