Module:Jf-JSON
[voir] [modifier] [historique] [purger]
Attention :
Il est probablement préférable d’utiliser mw.text.jsonEncode et mw.text.jsonDecode
Ceci est le librairie JSON.lua de Jeffrey Friedl, copiée depuis http://regex.info/blog/lua/json (code source), disponible sous licence CC-BY 3.0.
Utilisation
[modifier le code]decode( texte ): transforme un texte JSON en table luaencode( table ): transforme une table ou une valeur lua au format JSONencode_pretty( table ): transforme une table ou une valeur lua au format JSON en ajoutant des espaces et retour ligne pour que ce soit plus lisible par un utilisateur humain.
Pour plus d'option, voir la documentation dans le code source.
Exemple
[modifier le code]Chargement
[modifier le code]Le module se charge comme tout module Scribunto :
local JSON = require( 'Module:jf-JSON' )
Note : le code proposé pour charger le module dans la documentation officielle « JSON = assert(loadfile "JSON.lua")() » ne fonctionne pas sur Scribunto / Wikipédia.
Décoder du JSON
[modifier le code]local varialbe_lua = JSON:decode( '{ "objet": "livre", "nombre": 3 }' )
Encoder au format JSON
[modifier le code]- →
local texte_json_brut = JSON:encode( { objet = 'livre', nombre = 3 } )
{"nombre":3,"objet":"livre"}
- →
local texte_json_lisible = JSON:encode_pretty( { objet = 'livre', nombre = 3 } )
{ "nombre": 3, "objet": "livre" }
La documentation de ce module est générée par le modèle {{Documentation module}}.
Elle est incluse depuis sa sous-page de documentation. Veuillez placer les catégories sur cette page-là.
Les éditeurs peuvent travailler dans le bac à sable (créer).
Voir les statistiques d'appel depuis le wikicode sur l'outil wstat et les appels depuis d'autres modules.
-- -*- coding: utf-8 -*-
--
-- Simple JSON encoding and decoding in pure Lua.
--
-- Copyright 2010-2016 Jeffrey Friedl
-- http://regex.info/blog/
-- Latest version: http://regex.info/blog/lua/json
--
-- This code is released under a Creative Commons CC-BY "Attribution" License:
-- http://creativecommons.org/licenses/by/3.0/deed.en_US
--
-- It can be used for any purpose so long as the copyright notice above,
-- the web-page links above, and the 'AUTHOR_NOTE' string below are
-- maintained. Enjoy.
--
local VERSION = 20160916.19 -- version history at end of file
local AUTHOR_NOTE = "-[ JSON.lua package by Jeffrey Friedl (http://regex.info/blog/lua/json) version 20160916.19 ]-"
--
-- The 'AUTHOR_NOTE' variable exists so that information about the source
-- of the package is maintained even in compiled versions. It's also
-- included in OBJDEF below mostly to quiet warnings about unused variables.
--
local OBJDEF = {
VERSION = VERSION,
AUTHOR_NOTE = AUTHOR_NOTE,
}
--
-- Simple JSON encoding and decoding in pure Lua.
-- JSON definition: http://www.json.org/
--
--
-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
--
-- local lua_value = JSON:decode(raw_json_text)
--
-- local raw_json_text = JSON:encode(lua_table_or_value)
-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
--
--
--
-- DECODING (from a JSON string to a Lua table)
--
--
-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
--
-- local lua_value = JSON:decode(raw_json_text)
--
-- If the JSON text is for an object or an array, e.g.
-- { "what": "books", "count": 3 }
-- or
-- [ "Larry", "Curly", "Moe" ]
--
-- the result is a Lua table, e.g.
-- { what = "books", count = 3 }
-- or
-- { "Larry", "Curly", "Moe" }
--
--
-- The encode and decode routines accept an optional second argument,
-- "etc", which is not used during encoding or decoding, but upon error
-- is passed along to error handlers. It can be of any type (including nil).
--
--
--
-- ERROR HANDLING
--
-- With most errors during decoding, this code calls
--
-- JSON:onDecodeError(message, text, location, etc)
--
-- with a message about the error, and if known, the JSON text being
-- parsed and the byte count where the problem was discovered. You can
-- replace the default JSON:onDecodeError() with your own function.
--
-- The default onDecodeError() merely augments the message with data
-- about the text and the location if known (and if a second 'etc'
-- argument had been provided to decode(), its value is tacked onto the
-- message as well), and then calls JSON.assert(), which itself defaults
-- to Lua's built-in assert(), and can also be overridden.
--
-- For example, in an Adobe Lightroom plugin, you might use something like
--
-- function JSON:onDecodeError(message, text, location, etc)
-- LrErrors.throwUserError("Internal Error: invalid JSON data")
-- end
--
-- or even just
--
-- function JSON.assert(message)
-- LrErrors.throwUserError("Internal Error: " .. message)
-- end
--
-- If JSON:decode() is passed a nil, this is called instead:
--
-- JSON:onDecodeOfNilError(message, nil, nil, etc)
--
-- and if JSON:decode() is passed HTML instead of JSON, this is called:
--
-- JSON:onDecodeOfHTMLError(message, text, nil, etc)
--
-- The use of the fourth 'etc' argument allows stronger coordination
-- between decoding and error reporting, especially when you provide your
-- own error-handling routines. Continuing with the the Adobe Lightroom
-- plugin example:
--
-- function JSON:onDecodeError(message, text, location, etc)
-- local note = "Internal Error: invalid JSON data"
-- if type(etc) = 'table' and etc.photo then
-- note = note .. " while processing for " .. etc.photo:getFormattedMetadata('fileName')
-- end
-- LrErrors.throwUserError(note)
-- end
--
-- :
-- :
--
-- for i, photo in ipairs(photosToProcess) do
-- :
-- :
-- local data = JSON:decode(someJsonText, { photo = photo })
-- :
-- :
-- end
--
--
--
--
--
-- DECODING AND STRICT TYPES
--
-- Because both JSON objects and JSON arrays are converted to Lua tables,
-- it's not normally possible to tell which original JSON type a
-- particular Lua table was derived from, or guarantee decode-encode
-- round-trip equivalency.
--
-- However, if you enable strictTypes, e.g.
--
-- JSON = assert(loadfile "JSON.lua")() --load the routines
-- JSON.strictTypes = true
--
-- then the Lua table resulting from the decoding of a JSON object or
-- JSON array is marked via Lua metatable, so that when re-encoded with
-- JSON:encode() it ends up as the appropriate JSON type.
--
-- (This is not the default because other routines may not work well with
-- tables that have a metatable set, for example, Lightroom API calls.)
--
--
-- ENCODING (from a lua table to a JSON string)
--
-- JSON = assert(loadfile "JSON.lua")() -- one-time load of the routines
--
-- local raw_json_text = JSON:encode(lua_table_or_value)
-- local pretty_json_text = JSON:encode_pretty(lua_table_or_value) -- "pretty printed" version for human readability
-- local custom_pretty = JSON:encode(lua_table_or_value, etc, { pretty = true, indent = "| ", align_keys = false })
--
-- On error during encoding, this code calls:
--
-- JSON:onEncodeError(message, etc)
--
-- which you can override in your local JSON object.
--
-- The 'etc' in the error call is the second argument to encode()
-- and encode_pretty(), or nil if it wasn't provided.
--
--
-- ENCODING OPTIONS
--
-- An optional third argument, a table of options, can be provided to encode().
--
-- encode_options = {
-- -- options for making "pretty" human-readable JSON (see "PRETTY-PRINTING" below)
-- pretty = true,
-- indent = " ",
-- align_keys = false,
--
-- -- other output-related options
-- null = "\0", -- see "ENCODING JSON NULL VALUES" below
-- stringsAreUtf8 = false, -- see "HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA" below
-- }
--
-- json_string = JSON:encode(mytable, etc, encode_options)
--
--
--
-- For reference, the defaults are:
--
-- pretty = false
-- null = nil,
-- stringsAreUtf8 = false,
--
--
--
-- PRETTY-PRINTING
--
-- Enabling the 'pretty' encode option helps generate human-readable JSON.
--
-- pretty = JSON:encode(val, etc, {
-- pretty = true,
-- indent = " ",
-- align_keys = false,
-- })
--
-- encode_pretty() is also provided: it's identical to encode() except
-- that encode_pretty() provides a default options table if none given in the call:
--
-- { pretty = true, align_keys = false, indent = " " }
--
-- For example, if
--
-- JSON:encode(data)
--
-- produces:
--
-- {"city":"Kyoto","climate":{"avg_temp":16,"humidity":"high","snowfall":"minimal"},"country":"Japan","wards":11}
--
-- then
--
-- JSON:encode_pretty(data)
--
-- produces:
--
-- {
-- "city": "Kyoto",
-- "climate": {
-- "avg_temp": 16,
-- "humidity": "high",
-- "snowfall": "minimal"
-- },
-- "country": "Japan",
-- "wards": 11
-- }
--
-- The following three lines return identical results:
-- JSON:encode_pretty(data)
-- JSON:encode_pretty(data, nil, { pretty = true, align_keys = false, indent = " " })
-- JSON:encode (data, nil, { pretty = true, align_keys = false, indent = " " })
--
-- An example of setting your own indent string:
--
-- JSON:encode_pretty(data, nil, { pretty = true, indent = "| " })
--
-- produces:
--
-- {
-- | "city": "Kyoto",
-- | "climate": {
-- | | "avg_temp": 16,
-- | | "humidity": "high",
-- | | "snowfall": "minimal"
-- | },
-- | "country": "Japan",
-- | "wards": 11
-- }
--
-- An example of setting align_keys to true:
--
-- JSON:encode_pretty(data, nil, { pretty = true, indent = " ", align_keys = true })
--
-- produces:
--
-- {
-- "city": "Kyoto",
-- "climate": {
-- "avg_temp": 16,
-- "humidity": "high",
-- "snowfall": "minimal"
-- },
-- "country": "Japan",
-- "wards": 11
-- }
--
-- which I must admit is kinda ugly, sorry. This was the default for
-- encode_pretty() prior to version 20141223.14.
--
--
-- HANDLING UNICODE LINE AND PARAGRAPH SEPARATORS FOR JAVA
--
-- If the 'stringsAreUtf8' encode option is set to 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 being dumped as is.
-- The JSON is valid either way, but encoding this way, apparently, allows the resulting JSON
-- to also be valid Java.
--
-- AMBIGUOUS SITUATIONS DURING THE ENCODING
--
-- During the encode, if a Lua table being encoded contains both string
-- and numeric keys, it fits neither JSON's idea of an object, nor its
-- idea of an array. To get around this, when any string key exists (or
-- when non-positive numeric keys exist), numeric keys are converted to
-- strings.
--
-- For example,
-- JSON:encode({ "one", "two", "three", SOMESTRING = "some string" }))
-- produces the JSON object
-- {"1":"one","2":"two","3":"three","SOMESTRING":"some string"}
--
-- To prohibit this conversion and instead make it an error condition, set
-- JSON.noKeyConversion = true
--
--
-- ENCODING JSON NULL VALUES
--
-- Lua tables completely omit keys whose value is nil, so without special handling there's
-- no way to get a field in a JSON object with a null value. For example
-- JSON:encode({ username = "admin", password = nil })
-- produces
-- {"username":"admin"}
--
-- In order to actually produce
-- {"username":"admin", "password":null}
-- one can include a string value for a "null" field in the options table passed to encode()....
-- any Lua table entry with that value becomes null in the JSON output:
-- JSON:encode({ username = "admin", password = "xyzzy" }, nil, { null = "xyzzy" })
-- produces
-- {"username":"admin", "password":null}
--
-- Just be sure to use a string that is otherwise unlikely to appear in your data.
-- The string "\0" (a string with one null byte) may well be appropriate for many applications.
--
-- The "null" options also applies to Lua tables that become JSON arrays.
-- JSON:encode({ "one", "two", nil, nil })
-- produces
-- ["one","two"]
-- while
-- NULL = "\0"
-- JSON:encode({ "one", "two", NULL, NULL}, nil, { null = NULL })
-- produces
-- ["one","two",null,null]
--
--
--
--
-- HANDLING LARGE AND/OR PRECISE NUMBERS
--
--
-- Without special handling, numbers in JSON can lose precision in Lua.
-- For example:
--
-- 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: number 1.2345678901235e+28
-- precise: number 9876.6789012346
--
-- Precision is lost with both 'big' and 'precise'.
--
-- This package offers ways to try to handle this better (for some definitions of "better")...
--
-- The most precise method is by setting the global:
--
-- JSON.decodeNumbersAsObjects = true
--
-- When this is set, numeric JSON data is encoded into Lua in a form that preserves the exact
-- JSON numeric presentation when re-encoded back out to JSON, or accessed in Lua as a string.
--
-- (This is done by encoding the numeric data with a Lua table/metatable that returns
-- the possibly-imprecise numeric form when accessed numerically, but the original precise
-- representation when accessed as a string. You can also explicitly access
-- via JSON:forceString() and JSON:forceNumber())
--
-- Consider the example above, with this option turned on:
--
-- JSON.decodeNumbersAsObjects = true
--
-- 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 now produces:
--
-- small: table 12345
-- big: table 12345678901234567890123456789
-- precise: table 9876.67890123456789012345
--
-- However, within Lua you can still use the values (e.g. T.precise in the example above) in numeric
-- contexts. In such cases you'll get the possibly-imprecise numeric version, but in string contexts
-- and when the data finds its way to this package's encode() function, the original full-precision
-- representation is used.
--
-- Even without using the JSON.decodeNumbersAsObjects option, you can encode numbers
-- in your Lua table that retain high precision upon encoding to JSON, by using the JSON:asNumber()
-- function:
--
-- T = {
-- imprecise = 123456789123456789.123456789123456789,
-- precise = JSON:asNumber("123456789123456789.123456789123456789")
-- }
--
-- print(JSON:encode_pretty(T))
--
-- This produces:
--
-- {
-- "precise": 123456789123456789.123456789123456789,
-- "imprecise": 1.2345678912346e+17
-- }
--
--
--
-- A different way to handle big/precise JSON numbers is to have decode() merely return
-- the exact 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 in Lua as strings anyway.
--
-- This approach is enabled by setting
--
-- JSON.decodeIntegerStringificationLength = 10
--
-- The value is the number of digits (of the integer part of the number) at which to stringify numbers.
--
-- 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.
--
-- 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
--
--
--
--
--
-- SUMMARY OF METHODS YOU CAN OVERRIDE IN YOUR LOCAL LUA JSON OBJECT
--
-- assert
-- onDecodeError
-- onDecodeOfNilError
-- onDecodeOfHTMLError
-- onEncodeError
--
-- 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, align_keys = false, indent = default_pretty_indent }
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
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 char %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
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)
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
return OBJDEF:asNumber(full_number_text), i
end
--
-- If we're told to stringify 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
local as_number = tonumber(full_number_text)
if not as_number then
self:onDecodeError("bad number", text, start, options.etc)
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)
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)
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)
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)
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)
end
i = skip_whitespace(text, i + 1)
end
self:onDecodeError("unclosed '{'", text, start, options.etc)
end
local function grok_array(self, text, start, options)
if text:sub(start,start) ~= '[' then
self:onDecodeError("expected '['", text, start, options.etc)
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)
end
i = skip_whitespace(text, i + 1)
end
self:onDecodeError("unclosed '['", text, start, options.etc)
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)
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 nil, start + 4
else
self:onDecodeError("can't parse JSON", text, start, options.etc)
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
OBJDEF:onDecodeError("JSON:decode must be called in method format", nil, nil, options.etc)
end
if text == nil then
self:onDecodeOfNilError(string.format("nil passed to JSON:decode()"), nil, nil, options.etc)
elseif type(text) ~= 'string' then
self:onDecodeError(string.format("expected string argument to JSON:decode(), got %s", type(text)), nil, nil, options.etc)
end
if text:match('^%s*$') then
return nil
end
if text:match('^%s*<') then
-- Can't be JSON... we'll assume it's HTML
self:onDecodeOfHTMLError(string.format("html passed to JSON:decode()"), text, nil, options.etc)
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
self:onDecodeError("JSON package groks only UTF-8, sorry", text, nil, options.etc)
end
--
-- apply global options
--
if options.decodeNumbersAsObjects == nil then
options.decodeNumbersAsObjects = self.decodeNumbersAsObjects
end
if options.decodeIntegerStringificationLength == nil then
options.decodeIntegerStringificationLength = self.decodeIntegerStringificationLength
end
if options.decodeDecimalStringificationLength == nil then
options.decodeDecimalStringificationLength = self.decodeDecimalStringificationLength
end
local success, value = pcall(grok_one, self, text, 1, options)
if success then
return value
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.
if self.assert then
self.assert(false, value)
else
assert(false, value)
end
-- and if we're still here, return a nil and throw the error message on as a second arg
return nil, value
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
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.
--
-- 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 encode_value -- must predeclare because it calls itself
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
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 ITEMS = { }
for i = 1, maximum_number_key do
table.insert(ITEMS, encode_value(self, T[i], parents, etc, options, indent))
end
if 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
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 encode_value(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 encode_value(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:
--
-- 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
--