milis/bin/json

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2017-06-27 23:46:51 +02:00
#!/usr/bin/env node
/**
* Copyright (c) 2014 Trent Mick. All rights reserved.
* Copyright (c) 2014 Joyent Inc. All rights reserved.
*
* json -- JSON love for your command line.
*
* See <https://github.com/trentm/json> and <https://trentm.com/json/>
*/
var VERSION = '9.0.6';
var p = console.warn;
var util = require('util');
var assert = require('assert');
var path = require('path');
var vm = require('vm');
var fs = require('fs');
var warn = console.warn;
var EventEmitter = require('events').EventEmitter;
//--- exports for module usage
exports.main = main;
exports.getVersion = getVersion;
exports.parseLookup = parseLookup;
// As an exported API, these are still experimental:
exports.lookupDatum = lookupDatum;
exports.printDatum = printDatum; // DEPRECATED
//---- globals and constants
// Output modes.
var OM_JSONY = 1;
var OM_JSON = 2;
var OM_INSPECT = 3;
var OM_COMPACT = 4;
var OM_FROM_NAME = {
'jsony': OM_JSONY,
'json': OM_JSON,
'inspect': OM_INSPECT,
'compact': OM_COMPACT
};
//---- support functions
function getVersion() {
return VERSION;
}
/**
* Return a *shallow* copy of the given object.
*
* Only support objects that you get out of JSON, i.e. no functions.
*/
function objCopy(obj) {
var copy;
if (Array.isArray(obj)) {
copy = obj.slice();
} else if (typeof (obj) === 'object') {
copy = {};
Object.keys(obj).forEach(function (k) {
copy[k] = obj[k];
});
} else {
copy = obj; // immutable type
}
return copy;
}
if (util.format) {
format = util.format;
} else {
// From <https://github.com/joyent/node/blob/master/lib/util.js#L22>:
var formatRegExp = /%[sdj%]/g;
function format(f) {
var i;
if (typeof (f) !== 'string') {
var objects = [];
for (i = 0; i < arguments.length; i++) {
objects.push(util.inspect(arguments[i]));
}
return objects.join(' ');
}
i = 1;
var args = arguments;
var len = args.length;
var str = String(f).replace(formatRegExp, function (x) {
if (i >= len)
return x;
switch (x) {
case '%s':
return String(args[i++]);
case '%d':
return Number(args[i++]);
case '%j':
return JSON.stringify(args[i++]);
case '%%':
return '%';
default:
return x;
}
});
for (var x = args[i]; i < len; x = args[++i]) {
if (x === null || typeof (x) !== 'object') {
str += ' ' + x;
} else {
str += ' ' + util.inspect(x);
}
}
return str;
}
}
/**
* Parse the given string into a JS string. Basically: handle escapes.
*/
function _parseString(s) {
/* JSSTYLED */
var quoted = '"' + s.replace(/\\"/, '"').replace('"', '\\"') + '"';
return eval(quoted);
}
// json_parse.js (<https://github.com/douglascrockford/JSON-js>)
/* BEGIN JSSTYLED */
// START json_parse
var json_parse=function(){"use strict";var a,b,c={'"':'"',"\\":"\\","/":"/",b:"\b",f:"\f",n:"\n",r:"\r",t:"\t"},d,e=function(b){throw{name:"SyntaxError",message:b,at:a,text:d}},f=function(c){return c&&c!==b&&e("Expected '"+c+"' instead of '"+b+"'"),b=d.charAt(a),a+=1,b},g=function(){var a,c="";b==="-"&&(c="-",f("-"));while(b>="0"&&b<="9")c+=b,f();if(b==="."){c+=".";while(f()&&b>="0"&&b<="9")c+=b}if(b==="e"||b==="E"){c+=b,f();if(b==="-"||b==="+")c+=b,f();while(b>="0"&&b<="9")c+=b,f()}a=+c;if(!isFinite(a))e("Bad number");else return a},h=function(){var a,d,g="",h;if(b==='"')while(f()){if(b==='"')return f(),g;if(b==="\\"){f();if(b==="u"){h=0;for(d=0;d<4;d+=1){a=parseInt(f(),16);if(!isFinite(a))break;h=h*16+a}g+=String.fromCharCode(h)}else if(typeof c[b]=="string")g+=c[b];else break}else g+=b}e("Bad string")},i=function(){while(b&&b<=" ")f()},j=function(){switch(b){case"t":return f("t"),f("r"),f("u"),f("e"),!0;case"f":return f("f"),f("a"),f("l"),f("s"),f("e"),!1;case"n":return f("n"),f("u"),f("l"),f("l"),null}e("Unexpected '"+b+"'")},k,l=function(){var a=[];if(b==="["){f("["),i();if(b==="]")return f("]"),a;while(b){a.push(k()),i();if(b==="]")return f("]"),a;f(","),i()}}e("Bad array")},m=function(){var a,c={};if(b==="{"){f("{"),i();if(b==="}")return f("}"),c;while(b){a=h(),i(),f(":"),Object.hasOwnProperty.call(c,a)&&e('Duplicate key "'+a+'"'),c[a]=k(),i();if(b==="}")return f("}"),c;f(","),i()}}e("Bad object")};return k=function(){i();switch(b){case"{":return m();case"[":return l();case'"':return h();case"-":return g();default:return b>="0"&&b<="9"?g():j()}},function(c,f){var g;return d=c,a=0,b=" ",g=k(),i(),b&&e("Syntax error"),typeof f=="function"?function h(a,b){var c,d,e=a[b];if(e&&typeof e=="object")for(c in e)Object.prototype.hasOwnProperty.call(e,c)&&(d=h(e,c),d!==undefined?e[c]=d:delete e[c]);return f.call(a,b,e)}({"":g},""):g}}();
// END json_parse
/* END JSSTYLED */
function printHelp() {
/* BEGIN JSSTYLED */
var w = console.log;
w('Usage:');
w(' <something generating JSON on stdout> | json [OPTIONS] [LOOKUPS...]');
w(' json -f FILE [OPTIONS] [LOOKUPS...]');
w('');
w('Pipe in your JSON for pretty-printing, JSON validation, filtering, ');
w('and modification. Supply one or more `LOOKUPS` to extract a ');
w('subset of the JSON. HTTP header blocks are skipped by default.');
w('Roughly in order of processing, features are:');
w('');
w('Grouping:');
w(' Use "-g" or "--group" to group adjacent objects, separated by');
w(' by no space or a by a newline, or adjacent arrays, separate by');
w(' by a newline. This can be helpful for, e.g.: ');
w(' $ cat *.json | json -g ... ');
w(' and similar.');
w('');
w('Execution:');
w(' Use the "-e CODE" option to execute JavaScript code on the input JSON.');
w(' $ echo \'{"name":"trent","age":38}\' | json -e \'this.age++\'');
w(' {');
w(' "name": "trent",');
w(' "age": 39');
w(' }');
w(' If input is an array, this will automatically process each');
w(' item separately.');
w('');
w('Conditional filtering:');
w(' Use the "-c CODE" option to filter the input JSON.');
w(' $ echo \'[{"age":38},{"age":4}]\' | json -c \'this.age>21\'');
w(' [{\'age\':38}]');
w(' If input is an array, this will automatically process each');
w(' item separately. Note: "CODE" is JavaScript code.');
w('');
w('Lookups:');
w(' Use lookup arguments to extract particular values:');
w(' $ echo \'{"name":"trent","age":38}\' | json name');
w(' trent');
w('');
w(' Use "-a" for *array processing* of lookups and *tabular output*:');
w(' $ echo \'{"name":"trent","age":38}\' | json name age');
w(' trent');
w(' 38');
w(' $ echo \'[{"name":"trent","age":38},');
w(' {"name":"ewan","age":4}]\' | json -a name age');
w(' trent 38');
w(' ewan 4');
w('');
w('In-place editing:');
w(' Use "-I, --in-place" to edit a file in place:');
w(' $ json -I -f config.json # reformat');
w(' $ json -I -f config.json -c \'this.logLevel="debug"\' # add field');
w('');
w('Pretty-printing:');
w(' Output is "jsony" by default: 2-space indented JSON, except a');
w(' single string value is printed without quotes.');
w(' $ echo \'{"name": "trent", "age": 38}\' | json');
w(' {');
w(' "name": "trent",');
w(' "age": 38');
w(' }');
w(' $ echo \'{"name": "trent", "age": 38}\' | json name');
w(' trent');
w('');
w(" Use '-j' or '-o json' for explicit JSON, '-o json-N' for N-space indent:");
w(' $ echo \'{"name": "trent", "age": 38}\' | json -o json-0');
w(' {"name":"trent","age":38}');
w('');
w('Options:');
w(' -h, --help Print this help info and exit.');
w(' --version Print version of this command and exit.');
w(' -q, --quiet Don\'t warn if input isn\'t valid JSON.');
w('');
w(' -f FILE Path to a file to process. If not given, then');
w(' stdin is used.');
w(' -I, --in-place In-place edit of the file given with "-f".');
w(' Lookups are not allow with in-place editing');
w(' because it makes it too easy to lose content.');
w('');
w(' -H Drop any HTTP header block (as from `curl -i ...`).');
w(' -g, --group Group adjacent objects or arrays into an array.');
w(' --merge Merge adjacent objects into one. Keys in last ');
w(' object win.');
w(' --deep-merge Same as "--merge", but will recurse into objects ');
w(' under the same key in both.')
w(' -a, --array Process input as an array of separate inputs');
w(' and output in tabular form.');
w(' -A Process input as a single object, i.e. stop');
w(' "-e" and "-c" automatically processing each');
w(' item of an input array.');
w(' -d DELIM Delimiter char for tabular output (default is " ").');
w(' -D DELIM Delimiter char between lookups (default is "."). E.g.:');
w(' $ echo \'{"a.b": {"b": 1}}\' | json -D / a.b/b');
w('');
w(' -M, --items Itemize an object into an array of ');
w(' {"key": <key>, "value": <value>}');
w(' objects for easier processing.');
w('');
w(' -e CODE Execute the given JavaScript code on the input. If input');
w(' is an array, then each item of the array is processed');
w(' separately (use "-A" to override).');
w(' -c CODE Filter the input with JavaScript `CODE`. If `CODE`');
w(' returns false-y, then the item is filtered out. If');
w(' input is an array, then each item of the array is ');
w(' processed separately (use "-A" to override).');
w('');
w(' -k, --keys Output the input object\'s keys.');
w(' -n, --validate Just validate the input (no processing or output).');
w(' Use with "-q" for silent validation (exit status).');
w('');
w(' -o, --output MODE');
w(' Specify an output mode. One of:');
w(' jsony (default): JSON with string quotes elided');
w(' json: JSON output, 2-space indent');
w(' json-N: JSON output, N-space indent, e.g. "json-4"');
w(' inspect: node.js `util.inspect` output');
w(' -i Shortcut for `-o inspect`');
w(' -j Shortcut for `-o json`');
w(' -0, -2, -4 Set indentation to the given value w/o setting MODE.');
w(' -0 => -o jsony-0');
w(' -4 => -o jsony-4');
w(' -j0 => -o json-0');
w('');
w('See <http://trentm.com/json> for more docs and ');
w('<https://github.com/trentm/json> for project details.');
/* END JSSTYLED */
}
/**
* Parse the command-line options and arguments into an object.
*
* {
* 'args': [...] // arguments
* 'help': true, // true if '-h' option given
* // etc.
* }
*
* @return {Object} The parsed options. `.args` is the argument list.
* @throws {Error} If there is an error parsing argv.
*/
function parseArgv(argv) {
var parsed = {
args: [],
help: false,
quiet: false,
dropHeaders: false,
exeSnippets: [],
condSnippets: [],
outputMode: OM_JSONY,
jsonIndent: 2,
array: null,
delim: ' ',
lookupDelim: '.',
items: false,
outputKeys: false,
group: false,
merge: null, // --merge -> 'shallow', --deep-merge -> 'deep'
inputFiles: [],
validate: false,
inPlace: false
};
// Turn '-iH' into '-i -H', except for argument-accepting options.
var args = argv.slice(2); // drop ['node', 'scriptname']
var newArgs = [];
var optTakesArg = {
'd': true,
'o': true,
'D': true
};
for (var i = 0; i < args.length; i++) {
if (args[i] === '--') {
newArgs = newArgs.concat(args.slice(i));
break;
}
if (args[i].charAt(0) === '-' && args[i].charAt(1) !== '-' &&
args[i].length > 2)
{
var splitOpts = args[i].slice(1).split('');
for (var j = 0; j < splitOpts.length; j++) {
newArgs.push('-' + splitOpts[j])
if (optTakesArg[splitOpts[j]]) {
var optArg = splitOpts.slice(j + 1).join('');
if (optArg.length) {
newArgs.push(optArg);
}
break;
}
}
} else {
newArgs.push(args[i]);
}
}
args = newArgs;
endOfOptions = false;
while (args.length > 0) {
var arg = args.shift();
if (endOfOptions) {
parsed.args.push(arg);
break;
}
switch (arg) {
case '--':
endOfOptions = true;
break;
case '-h': // display help and exit
case '--help':
parsed.help = true;
break;
case '--version':
parsed.version = true;
break;
case '-q':
case '--quiet':
parsed.quiet = true;
break;
case '-H': // drop any headers
parsed.dropHeaders = true;
break;
case '-o':
case '--output':
var name = args.shift();
if (!name) {
throw new Error('no argument given for "-o|--output" option');
}
var idx = name.lastIndexOf('-');
if (idx !== -1) {
var indent = name.slice(idx + 1);
if (/^\d+$/.test(indent)) {
parsed.jsonIndent = Number(indent);
name = name.slice(0, idx);
} else if (indent === 'tab') {
parsed.jsonIndent = '\t';
name = name.slice(0, idx);
}
}
parsed.outputMode = OM_FROM_NAME[name];
if (parsed.outputMode === undefined) {
throw new Error('unknown output mode: "' + name + '"');
}
break;
case '-0':
parsed.jsonIndent = 0;
break;
case '-2':
parsed.jsonIndent = 2;
break;
case '-4':
parsed.jsonIndent = 4;
break;
case '-I':
case '--in-place':
parsed.inPlace = true;
break;
case '-i': // output with util.inspect
parsed.outputMode = OM_INSPECT;
break;
case '-j': // output with JSON.stringify
parsed.outputMode = OM_JSON;
break;
case '-a':
case '--array':
parsed.array = true;
break;
case '-A':
parsed.array = false;
break;
case '-d':
parsed.delim = _parseString(args.shift());
break;
case '-D':
parsed.lookupDelim = args.shift();
if (parsed.lookupDelim.length !== 1) {
throw new Error(format(
'invalid lookup delim "%s" (must be a single char)',
parsed.lookupDelim));
}
break;
case '-e':
case '-E': // DEPRECATED in v9
parsed.exeSnippets.push(args.shift());
break;
case '-c':
case '-C': // DEPRECATED in v9
parsed.condSnippets.push(args.shift());
break;
case '-M':
case '--items':
parsed.items = true;
break;
case '-k':
case '--keys':
parsed.outputKeys = true;
break;
case '-g':
case '--group':
parsed.group = true;
break;
case '--merge':
parsed.merge = 'shallow';
break;
case '--deep-merge':
parsed.merge = 'deep';
break;
case '-f':
parsed.inputFiles.push(args.shift());
break;
case '-n':
case '--validate':
parsed.validate = true;
break;
default: // arguments
if (!endOfOptions && arg.length > 0 && arg[0] === '-') {
throw new Error('unknown option "' + arg + '"');
}
parsed.args.push(arg);
break;
}
}
if (parsed.group && parsed.merge) {
throw new Error('cannot use -g|--group and --merge options together');
}
if (parsed.outputKeys && parsed.args.length > 0) {
throw new Error(
'cannot use -k|--keys option and lookup arguments together');
}
if (parsed.inPlace && parsed.inputFiles.length !== 1) {
throw new Error('must specify exactly one file with "-f FILE" to ' +
'use -I/--in-place');
}
if (parsed.inPlace && parsed.args.length > 0) {
throw new Error('lookups cannot be specified with in-place editing ' +
'(-I/--in-place), too easy to lose content');
}
return parsed;
}
/**
* Streams chunks from given file paths or stdin.
*
* @param opts {Object} Parsed options.
* @returns {Object} An emitter that emits 'chunk', 'error', and 'end'.
* - `emit('chunk', chunk, [obj])` where chunk is a complete block of JSON
* ready to parse. If `obj` is provided, it is the already parsed
* JSON.
* - `emit('error', error)` when an underlying stream emits an error
* - `emit('end')` when all streams are done
*/
function chunkEmitter(opts) {
var emitter = new EventEmitter();
var streaming = true;
var chunks = [];
var leftover = '';
var finishedHeaders = false;
function stripHeaders(s) {
// Take off a leading HTTP header if any and pass it through.
while (true) {
if (s.slice(0, 5) === 'HTTP/') {
var index = s.indexOf('\r\n\r\n');
var sepLen = 4;
if (index == -1) {
index = s.indexOf('\n\n');
sepLen = 2;
}
if (index != -1) {
if (!opts.dropHeaders) {
emit(s.slice(0, index + sepLen));
}
var is100Continue = (
s.slice(0, 21) === 'HTTP/1.1 100 Continue');
s = s.slice(index + sepLen);
if (is100Continue) {
continue;
}
finishedHeaders = true;
}
} else {
finishedHeaders = true;
}
break;
}
//console.warn('stripHeaders done, finishedHeaders=%s', finishedHeaders)
return s;
}
function emitChunks(block, emitter) {
//console.warn('emitChunks start: block="%s"', block)
/* JSSTYLED */
var splitter = /(})(\s*\n\s*)?({\s*")/;
var leftTrimmedBlock = block.trimLeft();
if (leftTrimmedBlock && leftTrimmedBlock[0] !== '{') {
// Currently only support streaming consecutive *objects*.
streaming = false;
chunks.push(block);
return '';
}
/**
* Example:
* > '{"a":"b"}\n{"a":"b"}\n{"a":"b"}'.split(/(})(\s*\n\s*)?({\s*")/)
* [ '{"a":"b"',
* '}',
* '\n',
* '{"',
* 'a":"b"',
* '}',
* '\n',
* '{"',
* 'a":"b"}' ]
*/
var bits = block.split(splitter);
//console.warn('emitChunks: bits (length %d): %j', bits.length, bits);
if (bits.length === 1) {
/*
* An unwanted side-effect of using a regex to find
* newline-separated objects *with a regex*, is that we are looking
* for the end of one object leading into the start of a another.
* That means that we can end up buffering a complete object until
* a subsequent one comes in. If the input stream has large delays
* between objects, then this is unwanted buffering.
*
* One solution would be full stream parsing of objects a la
* <https://github.com/creationix/jsonparse>. This would nicely
* also remove the artibrary requirement that the input stream be
* newline separated. jsonparse apparently has some issues tho, so
* I don't want to use it right now. It also isn't *small* so not
* sure I want to inline it (`json` doesn't have external deps).
*
* An alternative: The block we have so far one of:
* 1. some JSON that we don't support grouping (e.g. a stream of
* non-objects),
* 2. a JSON object fragment, or
* 3. a complete JSON object (with a possible trailing '{')
*
* If #3, then we can just emit this as a chunk right now.
*
* TODO(PERF): Try out avoiding the first more complete regex split
* for a presumed common case of single-line newline-separated JSON
* objects (e.g. a bunyan log).
*/
// An object must end with '}'. This is an early out to avoid
// `JSON.parse` which I'm *presuming* is slower.
var trimmed = block.split(/\s*\r?\n/)[0];
if (trimmed[trimmed.length - 1] === '}') {
var obj;
try {
obj = JSON.parse(block);
} catch (e) {
/* pass through */
}
if (obj !== undefined) {
// Emit the parsed `obj` to avoid re-parsing it later.
emitter.emit('chunk', block, obj);
block = '';
}
}
return block;
} else {
var n = bits.length - 2;
var s;
s = bits[0] + bits[1];
emitter.emit('chunk', s, JSON.parse(s));
for (var i = 3; i < n; i += 4) {
s = bits[i] + bits[i + 1] + bits[i + 2];
emitter.emit('chunk', s, JSON.parse(s));
}
return bits[n] + bits[n + 1];
}
}
function addDataListener(stream) {
stream.on('data', function (chunk) {
var s = leftover + chunk;
if (!finishedHeaders) {
s = stripHeaders(s);
}
if (!finishedHeaders) {
leftover = s;
} else {
if (!streaming) {
chunks.push(chunk);
return;
}
if (chunk.lastIndexOf('\n') >= 0) {
leftover = emitChunks(s, emitter);
} else {
leftover = s;
}
}
});
}
if (opts.inputFiles.length > 0) {
// Stream each file in order.
var i = 0;
function addErrorListener(file) {
file.on('error', function (err) {
emitter.emit(
'error',
format('could not read "%s": %s', opts.inputFiles[i], e)
);
});
}
function addEndListener(file) {
file.on('end', function () {
if (i < opts.inputFiles.length) {
var next = opts.inputFiles[i++];
var nextFile = fs.createReadStream(next,
{encoding: 'utf8'});
addErrorListener(nextFile);
addEndListener(nextFile);
addDataListener(nextFile);
} else {
if (!streaming) {
emitter.emit('chunk', chunks.join(''));
} else if (leftover) {
leftover = emitChunks(leftover, emitter);
emitter.emit('chunk', leftover);
}
emitter.emit('end');
}
});
}
var first = fs.createReadStream(opts.inputFiles[i++],
{encoding: 'utf8'});
addErrorListener(first);
addEndListener(first);
addDataListener(first);
} else {
// Streaming from stdin.
var stdin = process.openStdin();
stdin.setEncoding('utf8');
addDataListener(stdin);
stdin.on('end', function () {
if (!streaming) {
emitter.emit('chunk', chunks.join(''));
} else if (leftover) {
leftover = emitChunks(leftover, emitter);
emitter.emit('chunk', leftover);
}
emitter.emit('end');
});
}
return emitter;
}
/**
* Get input from either given file paths or stdin. If `opts.inPlace` then
* this calls the callback once for each `opts.inputFiles`.
*
* @param opts {Object} Parsed options.
* @param callback {Function} `function (err, content, filename)` where err
* is an error string if there was a problem, `content` is the read
* content and `filename` is the associated file name from which content
* was loaded if applicable.
*/
function getInput(opts, callback) {
if (opts.inputFiles.length === 0) {
// Read from stdin.
var chunks = [];
var stdin = process.openStdin();
stdin.setEncoding('utf8');
stdin.on('data', function (chunk) {
chunks.push(chunk);
});
stdin.on('end', function () {
callback(null, chunks.join(''));
});
} else if (opts.inPlace) {
for (var i = 0; i < opts.inputFiles.length; i++) {
var file = opts.inputFiles[i];
var content;
try {
content = fs.readFileSync(file, 'utf8');
} catch (e) {
callback(e, null, file);
}
if (content) {
callback(null, content, file);
}
}
} else {
// Read input files.
var i = 0;
var chunks = [];
try {
for (; i < opts.inputFiles.length; i++) {
chunks.push(fs.readFileSync(opts.inputFiles[i], 'utf8'));
}
} catch (e) {
return callback(
format('could not read "%s": %s', opts.inputFiles[i], e));
}
callback(null, chunks.join(''),
(opts.inputFiles.length === 1 ? opts.inputFiles[0] : undefined));
}
}
function isInteger(s) {
return (s.search(/^-?[0-9]+$/) == 0);
}
/**
* Parse a lookup string into a list of lookup bits. E.g.:
*
* 'a.b.c' -> ["a","b","c"]
* 'b["a"]' -> ["b","a"]
* 'b["a" + "c"]' -> ["b","ac"]
*
* Optionally receives an alternative lookup delimiter (other than '.')
*/
function parseLookup(lookup, lookupDelim) {
var debug = function () {};
//var debug = console.warn;
var bits = [];
debug('\n*** ' + lookup + ' ***');
bits = [];
lookupDelim = lookupDelim || '.';
var bit = '';
var states = [null];
var escaped = false;
var ch = null;
for (var i = 0; i < lookup.length; ++i) {
var escaped = (!escaped && ch === '\\');
var ch = lookup[i];
debug('-- i=' + i + ', ch=' + JSON.stringify(ch) + ' escaped=' +
JSON.stringify(escaped));
debug('states: ' + JSON.stringify(states));
if (escaped) {
bit += ch;
continue;
}
switch (states[states.length - 1]) {
case null:
switch (ch) {
case '"':
case '\'':
states.push(ch);
bit += ch;
break;
case '[':
states.push(ch);
if (bit !== '') {
bits.push(bit);
bit = ''
}
bit += ch;
break;
case lookupDelim:
if (bit !== '') {
bits.push(bit);
bit = ''
}
break;
default:
bit += ch;
break;
}
break;
case '[':
bit += ch;
switch (ch) {
case '"':
case '\'':
case '[':
states.push(ch);
break;
case ']':
states.pop();
if (states[states.length - 1] === null) {
var evaled = vm.runInNewContext(
'(' + bit.slice(1, -1) + ')', {}, '<lookup>');
bits.push(evaled);
bit = ''
}
break;
}
break;
case '"':
bit += ch;
switch (ch) {
case '"':
states.pop();
if (states[states.length - 1] === null) {
bits.push(bit);
bit = ''
}
break;
}
break;
case '\'':
bit += ch;
switch (ch) {
case '\'':
states.pop();
if (states[states.length - 1] === null) {
bits.push(bit);
bit = ''
}
break;
}
break;
}
debug('bit: ' + JSON.stringify(bit));
debug('bits: ' + JSON.stringify(bits));
}
if (bit !== '') {
bits.push(bit);
bit = ''
}
// Negative-intify: strings that are negative ints we change to a Number for
// special handling in `lookupDatum`: Python-style negative array indexing.
var negIntPat = /^-\d+$/;
for (var i = 0; i < bits.length; i++) {
if (negIntPat.test(bits[i])) {
bits[i] = Number(bits[i]);
}
}
debug(JSON.stringify(lookup) + ' -> ' + JSON.stringify(bits));
return bits
}
/**
* Parse the given stdin input into:
* {
* 'error': ... error object if there was an error ...,
* 'datum': ... parsed object if content was JSON ...
* }
*
* @param buffer {String} The text to parse as JSON.
* @param obj {Object} Optional. Set when in streaming mode to avoid
* re-interpretation of `group`. Also avoids reparsing.
* @param group {Boolean} Default false. If true, then non-JSON input
* will be attempted to be 'arrayified' (see inline comment).
* @param merge {Boolean} Default null. Can be 'shallow' or 'deep'. An
* attempt will be made to interpret the input as adjacent objects to
* be merged, last key wins. See inline comment for limitations.
*/
function parseInput(buffer, obj, group, merge) {
if (obj) {
return {
datum: obj
};
} else if (group) {
/**
* Special case: Grouping (previously called auto-arrayification)
* of unjoined list of objects:
* {"one": 1}{"two": 2}
* and auto-concatenation of unjoined list of arrays:
* ["a", "b"]["c", "d"]
*
* This can be nice to process a stream of JSON objects generated from
* multiple calls to another tool or `cat *.json | json`.
*
* Rules:
* - Only JS objects and arrays. Don't see strong need for basic
* JS types right now and this limitation simplifies.
* - The break between JS objects has to include a newline:
* {"one": 1}
* {"two": 2}
* or no spaces at all:
* {"one": 1}{"two": 2}
* I.e., not this:
* {"one": 1} {"two": 2}
* This condition should be fine for typical use cases and ensures
* no false matches inside JS strings.
* - The break between JS *arrays* has to include a newline:
* ["one", "two"]
* ["three"]
* The 'no spaces' case is NOT supported for JS arrays as of v6.0.0
* because <https://github.com/trentm/json/issues/55> shows that that
* is not safe.
*/
var newBuffer = buffer;
/* JSSTYLED */
[/(})\s*\n\s*({)/g, /(})({")/g].forEach(function (pat) {
newBuffer = newBuffer.replace(pat, '$1,\n$2');
});
[/(\])\s*\n\s*(\[)/g].forEach(function (pat) {
newBuffer = newBuffer.replace(pat, ',\n');
});
newBuffer = newBuffer.trim();
if (newBuffer[0] !== '[') {
newBuffer = '[\n' + newBuffer;
}
if (newBuffer.slice(-1) !== ']') {
newBuffer = newBuffer + '\n]\n';
}
try {
return {
datum: JSON.parse(newBuffer)
};
} catch (e2) {
return {
error: e2
};
}
} else if (merge) {
// See the 'Rules' above for limitations on boundaries for 'adjacent'
// objects: KISS.
var newBuffer = buffer;
/* JSSTYLED */
[/(})\s*\n\s*({)/g, /(})({")/g].forEach(function (pat) {
newBuffer = newBuffer.replace(pat, '$1,\n$2');
});
newBuffer = '[\n' + newBuffer + '\n]\n';
var objs;
try {
objs = JSON.parse(newBuffer);
} catch (e) {
return {
error: e
};
}
var merged = objs[0];
if (merge === 'shallow') {
for (var i = 1; i < objs.length; i++) {
var obj = objs[i];
Object.keys(obj).forEach(function (k) {
merged[k] = obj[k];
});
}
} else if (merge === 'deep') {
function deepExtend(a, b) {
Object.keys(b).forEach(function (k) {
if (a[k] && b[k] &&
toString.call(a[k]) === '[object Object]' &&
toString.call(b[k]) === '[object Object]')
{
deepExtend(a[k], b[k])
} else {
a[k] = b[k];
}
});
}
for (var i = 1; i < objs.length; i++) {
deepExtend(merged, objs[i]);
}
} else {
throw new Error(format('unknown value for "merge": "%s"', merge));
}
return {
datum: merged
};
} else {
try {
return {
datum: JSON.parse(buffer)
};
} catch (e) {
return {
error: e
};
}
}
}
/**
* Apply a lookup to the given datum.
*
* @argument datum {Object}
* @argument lookup {Array} The parsed lookup (from
* `parseLookup(<string>, <string>)`). Might be empty.
* @returns {Object} The result of the lookup.
*/
function lookupDatum(datum, lookup) {
var d = datum;
for (var i = 0; i < lookup.length; i++) {
var bit = lookup[i];
if (d === null) {
return undefined;
} else if (typeof (bit) === 'number' && bit < 0) {
d = d[d.length + bit];
} else {
d = d[bit];
}
if (d === undefined) {
return undefined;
}
}
return d;
}
/**
* Output the given datasets.
*
* @param datasets {Array} Array of data sets to print, in the form:
* `[ [<datum>, <sep>, <alwaysPrintSep>], ... ]`
* @param filename {String} The filename to which to write the output. If
* not set, then emit to stdout.
* @param headers {String} The HTTP header block string, if any, to emit
* first.
* @param opts {Object} Parsed tool options.
*/
function printDatasets(datasets, filename, headers, opts) {
var isTTY = (filename ? false : process.stdout.isTTY)
var write = emit;
if (filename) {
var tmpPath = path.resolve(path.dirname(filename),
format('.%s-json-%s-%s.tmp', path.basename(filename), process.pid,
Date.now()));
var stats = fs.statSync(filename);
var f = fs.createWriteStream(tmpPath,
{encoding: 'utf8', mode: stats.mode});
write = f.write.bind(f);
}
if (headers && headers.length > 0) {
write(headers)
}
for (var i = 0; i < datasets.length; i++) {
var dataset = datasets[i];
var output = stringifyDatum(dataset[0], opts, isTTY);
var sep = dataset[1];
if (output && output.length) {
write(output);
write(sep);
} else if (dataset[2]) {
write(sep);
}
}
if (filename) {
f.on('open', function () {
f.end();
fs.renameSync(tmpPath, filename);
if (!opts.quiet) {
warn('json: updated "%s" in-place', filename);
}
});
}
}
/**
* Stringify the given datum according to the given output options.
*/
function stringifyDatum(datum, opts, isTTY) {
var output = null;
switch (opts.outputMode) {
case OM_INSPECT:
output = util.inspect(datum, false, Infinity, isTTY);
break;
case OM_JSON:
if (typeof (datum) !== 'undefined') {
output = JSON.stringify(datum, null, opts.jsonIndent);
}
break;
case OM_COMPACT:
// Dev Note: A still relatively experimental attempt at a more
// compact ouput somewhat a la Python's repr of a dict. I.e. try to
// fit elements on one line as much as reasonable.
if (datum === undefined) {
// pass
} else if (Array.isArray(datum)) {
var bits = ['[\n'];
datum.forEach(function (d) {
bits.push(' ')
bits.push(JSON.stringify(d, null, 0).replace(
/* JSSTYLED */
/,"(?![,:])/g, ', "'));
bits.push(',\n');
});
bits.push(bits.pop().slice(0, -2) + '\n') // drop last comma
bits.push(']');
output = bits.join('');
} else {
output = JSON.stringify(datum, null, 0);
}
break;
case OM_JSONY:
if (typeof (datum) === 'string') {
output = datum;
} else if (typeof (datum) !== 'undefined') {
output = JSON.stringify(datum, null, opts.jsonIndent);
}
break;
default:
throw new Error('unknown output mode: ' + opts.outputMode);
}
return output;
}
/**
* Print out a single result, considering input options.
*
* @deprecated
*/
function printDatum(datum, opts, sep, alwaysPrintSep) {
var output = stringifyDatum(datum, opts);
if (output && output.length) {
emit(output);
emit(sep);
} else if (alwaysPrintSep) {
emit(sep);
}
}
var stdoutFlushed = true;
function emit(s) {
// TODO:PERF If this is try/catch is too slow (too granular): move up to
// mainline and be sure to only catch this particular error.
if (drainingStdout) {
return;
}
try {
stdoutFlushed = process.stdout.write(s);
} catch (e) {
// Handle any exceptions in stdout writing in the 'error' event above.
}
}
process.stdout.on('error', function (err) {
if (err.code === 'EPIPE') {
// See <https://github.com/trentm/json/issues/9>.
drainStdoutAndExit(0);
} else {
warn(err)
drainStdoutAndExit(1);
}
});
/**
* A hacked up version of 'process.exit' that will first drain stdout
* before exiting. *WARNING: This doesn't stop event processing.* IOW,
* callers have to be careful that code following this call isn't
* accidentally executed.
*
* In node v0.6 "process.stdout and process.stderr are blocking when they
* refer to regular files or TTY file descriptors." However, this hack might
* still be necessary in a shell pipeline.
*/
var drainingStdout = false;
function drainStdoutAndExit(code) {
if (drainingStdout) {
return;
}
drainingStdout = true;
process.stdout.on('drain', function () {
process.exit(code);
});
process.stdout.on('close', function () {
process.exit(code);
});
if (stdoutFlushed) {
process.exit(code);
}
}
/**
* Return a function for the given JS code that returns.
*
* If no 'return' in the given javascript snippet, then assume we are a single
* statement and wrap in 'return (...)'. This is for convenience for short
* '-c ...' snippets.
*/
function funcWithReturnFromSnippet(js) {
// auto-"return"
if (js.indexOf('return') === -1) {
if (js.substring(js.length - 1) === ';') {
js = js.substring(0, js.length - 1);
}
js = 'return (' + js + ')';
}
return (new Function(js));
}
//---- mainline
function main(argv) {
var opts;
try {
opts = parseArgv(argv);
} catch (e) {
warn('json: error: %s', e.message)
return drainStdoutAndExit(1);
}
//warn(opts);
if (opts.help) {
printHelp();
return;
}
if (opts.version) {
if (opts.outputMode === OM_JSON) {
var v = {
version: getVersion(),
author: 'Trent Mick',
project: 'https://github.com/trentm/json'
};
console.log(JSON.stringify(v, null, opts.jsonIndent));
} else {
console.log('json ' + getVersion());
console.log('written by Trent Mick');
console.log('https://github.com/trentm/json');
}
return;
}
var lookupStrs = opts.args;
// Prepare condition and execution funcs (and vm scripts) for -c/-e.
var execVm = Boolean(process.env.JSON_EXEC &&
process.env.JSON_EXEC === 'vm');
var i;
var condFuncs = [];
if (!execVm) {
for (i = 0; i < opts.condSnippets.length; i++) {
condFuncs[i] = funcWithReturnFromSnippet(opts.condSnippets[i]);
}
}
var condScripts = [];
if (execVm) {
for (i = 0; i < opts.condSnippets.length; i++) {
condScripts[i] = vm.createScript(opts.condSnippets[i]);
}
}
var cond = Boolean(condFuncs.length + condScripts.length);
var exeFuncs = [];
if (!execVm) {
for (i = 0; i < opts.exeSnippets.length; i++) {
exeFuncs[i] = new Function(opts.exeSnippets[i]);
}
}
var exeScripts = [];
if (execVm) {
for (i = 0; i < opts.exeSnippets.length; i++) {
exeScripts[i] = vm.createScript(opts.exeSnippets[i]);
}
}
var exe = Boolean(exeFuncs.length + exeScripts.length);
var lookups = lookupStrs.map(function (lookup) {
return parseLookup(lookup, opts.lookupDelim);
});
if (opts.group && opts.array && opts.outputMode !== OM_JSON) {
// streaming
var chunker = chunkEmitter(opts);
chunker.on('error', function (error) {
warn('json: error: %s', err.message);
return drainStdoutAndExit(1);
});
chunker.on('chunk', parseChunk);
} else if (opts.inPlace) {
assert.equal(opts.inputFiles.length, 1,
'cannot handle more than one file with -I');
getInput(opts, function (err, content, filename) {
if (err) {
warn('json: error: %s', err.message)
return drainStdoutAndExit(1);
}
// Take off a leading HTTP header if any and pass it through.
var headers = [];
while (true) {
if (content.slice(0, 5) === 'HTTP/') {
var index = content.indexOf('\r\n\r\n');
var sepLen = 4;
if (index == -1) {
index = content.indexOf('\n\n');
sepLen = 2;
}
if (index != -1) {
if (!opts.dropHeaders) {
headers.push(content.slice(0, index + sepLen));
}
var is100Continue = (
content.slice(0, 21) === 'HTTP/1.1 100 Continue');
content = content.slice(index + sepLen);
if (is100Continue) {
continue;
}
}
}
break;
}
parseChunk(content, undefined, filename, true, headers.join(''));
});
} else {
// not streaming
getInput(opts, function (err, buffer, filename) {
if (err) {
warn('json: error: %s', err.message)
return drainStdoutAndExit(1);
}
// Take off a leading HTTP header if any and pass it through.
while (true) {
if (buffer.slice(0, 5) === 'HTTP/') {
var index = buffer.indexOf('\r\n\r\n');
var sepLen = 4;
if (index == -1) {
index = buffer.indexOf('\n\n');
sepLen = 2;
}
if (index != -1) {
if (!opts.dropHeaders) {
emit(buffer.slice(0, index + sepLen));
}
var is100Continue = (
buffer.slice(0, 21) === 'HTTP/1.1 100 Continue');
buffer = buffer.slice(index + sepLen);
if (is100Continue) {
continue;
}
}
}
break;
}
parseChunk(buffer, null, filename, false);
});
}
/**
* Parse a single chunk of JSON. This may be called more than once
* (when streaming or when operating on multiple files).
*
* @param chunk {String} The JSON-encoded string.
* @param obj {Object} Optional. For some code paths while streaming `obj`
* will be provided. This is an already parsed JSON object.
* @param filename {String} Optional. The filename from which this content
* came, if relevant.
* @param inPlace {Boolean} Optional. If true, then output will be written
* to `filename`.
* @param headers {String} Optional. Leading HTTP headers, if any to emit.
*/
function parseChunk(chunk, obj, filename, inPlace, headers) {
// Expect the chunk to be JSON.
if (!chunk.length) {
return;
}
// parseInput() -> {datum: <input object>, error: <error object>}
var input = parseInput(chunk, obj, opts.group, opts.merge);
if (input.error) {
// Doesn't look like JSON. Just print it out and move on.
if (!opts.quiet) {
// Use JSON-js' "json_parse" parser to get more detail on the
// syntax error.
var details = '';
var normBuffer = chunk.replace(/\r\n|\n|\r/, '\n');
try {
json_parse(normBuffer);
details = input.error;
} catch (err) {
// err.at has the position. Get line/column from that.
var at = err.at - 1; // `err.at` looks to be 1-based.
var lines = chunk.split('\n');
var line, col, pos = 0;
for (line = 0; line < lines.length; line++) {
pos += lines[line].length + 1;
if (pos > at) {
col = at - (pos - lines[line].length - 1);
break;
}
}
var spaces = '';
for (var i = 0; i < col; i++) {
spaces += '.';
}
details = err.message + ' at line ' + (line + 1) +
', column ' + (col + 1) + ':\n ' +
lines[line] + '\n ' + spaces + '^';
}
warn('json: error: %s is not JSON: %s',
filename ? '"' + filename + '"' : 'input', details);
}
if (!opts.validate) {
emit(chunk);
if (chunk.length && chunk[chunk.length - 1] !== '\n') {
emit('\n');
}
}
return drainStdoutAndExit(1);
}
if (opts.validate) {
return drainStdoutAndExit(0);
}
var data = input.datum;
// Process: items (-M, --items)
if (opts.items) {
if (!Array.isArray(data)) {
var key;
var array = [];
for (key in data) {
if (data.hasOwnProperty(key)) {
array.push({
key: key,
value: data[key]
});
}
}
data = array;
}
}
// Process: executions (-e, -E)
var i, j;
if (!exe) {
/* pass */
} else if (opts.array || (opts.array === null && Array.isArray(data))) {
var arrayified = false;
if (!Array.isArray(data)) {
arrayified = true;
data = [data];
}
for (i = 0; i < data.length; i++) {
var datum = data[i];
for (j = 0; j < exeFuncs.length; j++) {
exeFuncs[j].call(datum);
}
for (j = 0; j < exeScripts.length; j++) {
exeScripts[j].runInNewContext(datum);
}
}
if (arrayified) {
data = data[0];
}
} else {
for (j = 0; j < exeFuncs.length; j++) {
exeFuncs[j].call(data);
}
for (j = 0; j < exeScripts.length; j++) {
exeScripts[j].runInNewContext(data);
}
}
// Process: conditionals (-c)
if (!cond) {
/* pass */
} else if (opts.array || (opts.array === null && Array.isArray(data))) {
var arrayified = false;
if (!Array.isArray(data)) {
arrayified = true;
data = [data];
}
var filtered = [];
for (i = 0; i < data.length; i++) {
var datum = data[i];
var datumCopy = objCopy(datum);
var keep = true;
// TODO(perf): Perhaps drop the 'datumCopy'? "this is a gun"
for (j = 0; j < condFuncs.length; j++) {
if (!condFuncs[j].call(datumCopy)) {
keep = false;
break;
}
}
if (keep) {
for (j = 0; j < condScripts.length; j++) {
if (!condScripts[j].runInNewContext(datumCopy)) {
keep = false;
break;
}
}
if (keep) {
filtered.push(datum);
}
}
}
if (arrayified) {
data = (filtered.length ? filtered[0] : []);
} else {
data = filtered;
}
} else {
var keep = true;
var dataCopy = objCopy(data);
for (j = 0; j < condFuncs.length; j++) {
// TODO(perf): Perhaps drop the 'dataCopy'? "this is a gun"
if (!condFuncs[j].call(dataCopy)) {
keep = false;
break;
}
}
if (keep) {
for (j = 0; j < condScripts.length; j++) {
if (!condScripts[j].runInNewContext(dataCopy)) {
keep = false;
break;
}
}
}
if (!keep) {
data = undefined;
}
}
// Process: lookups
var lookupsAreIndeces = false;
if (lookups.length) {
if (opts.array) {
if (!Array.isArray(data)) data = [data];
var table = [];
for (j = 0; j < data.length; j++) {
var datum = data[j];
var row = {};
for (i = 0; i < lookups.length; i++) {
var lookup = lookups[i];
var value = lookupDatum(datum, lookup);
if (value !== undefined) {
row[lookup.join('.')] = value;
}
}
table.push(row);
}
data = table;
} else {
// Special case handling: Note if the 'lookups' are indeces into
// an array. This may be used below to change the output
// representation.
if (Array.isArray(data)) {
lookupsAreIndeces = true;
for (i = 0; i < lookups.length; i++) {
if (lookups[i].length !== 1 ||
isNaN(Number(lookups[i])))
{
lookupsAreIndeces = false;
break;
}
}
}
var row = {};
for (i = 0; i < lookups.length; i++) {
var lookup = lookups[i];
var value = lookupDatum(data, lookup);
if (value !== undefined) {
row[lookup.join('.')] = value;
}
}
data = row;
}
}
// --keys
if (opts.outputKeys) {
var data = Object.keys(data);
}
// Output
var datasets = [];
if (opts.outputMode === OM_JSON) {
if (lookups.length === 1 && !opts.array) {
/**
* Special case: For JSON output of a *single* lookup, *don't*
* use the full table structure, else there is no way to get
* string quoting for a single value:
* $ echo '{"a": [], "b": "[]"}' | json -j a
* []
* $ echo '{"a": [], "b": "[]"}' | json -j b
* '[]'
* See <https://github.com/trentm/json/issues/35> for why.
*/
data = data[lookups[0].join('.')];
} else if (lookupsAreIndeces) {
/**
* Special case: Lookups that are all indeces into an input
* array are more likely to be wanted as an array of selected
* items rather than a 'JSON table' thing that we use otherwise.
*/
var flattened = [];
for (i = 0; i < lookups.length; i++) {
var lookupStr = lookups[i].join('.');
if (data.hasOwnProperty(lookupStr)) {
flattened.push(data[lookupStr])
}
}
data = flattened;
}
// If JSON output mode, then always just output full set of data to
// ensure valid JSON output.
datasets.push([data, '\n', false]);
} else if (lookups.length) {
if (opts.array) {
// Output `data` as a 'table' of lookup results.
for (j = 0; j < data.length; j++) {
var row = data[j];
for (i = 0; i < lookups.length - 1; i++) {
datasets.push([row[lookups[i].join('.')],
opts.delim, true]);
}
datasets.push([row[lookups[i].join('.')], '\n', true]);
}
} else {
for (i = 0; i < lookups.length; i++) {
datasets.push([data[lookups[i].join('.')], '\n', false]);
}
}
} else if (opts.array) {
if (!Array.isArray(data)) data = [data];
for (j = 0; j < data.length; j++) {
datasets.push([data[j], '\n', false]);
}
} else {
// Output `data` as is.
datasets.push([data, '\n', false]);
}
printDatasets(datasets, inPlace ? filename : undefined, headers, opts);
}
}
if (require.main === module) {
// HACK guard for <https://github.com/trentm/json/issues/24>.
// We override the `process.stdout.end` guard that core node.js puts in
// place. The real fix is that `.end()` shouldn't be called on stdout
// in node core. Hopefully node v0.6.9 will fix that. Only guard
// for v0.6.0..v0.6.8.
var nodeVer = process.versions.node.split('.').map(Number);
if ([0, 6, 0] <= nodeVer && nodeVer <= [0, 6, 8]) {
var stdout = process.stdout;
stdout.end = stdout.destroy = stdout.destroySoon = function () {
/* pass */
};
}
main(process.argv);
}