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Compatibility

This page describes the JavaScript surface provided by njs:

• the njs and nginx objects, built-in modules, and the Buffer object, available with both the QuickJS and njs engines;
• the ECMAScript language features implemented by the njs engine.

Definitions of njs specific properties and methods not compliant with ECMAScript can be found in Reference. Definitions of standard ECMAScript objects and methods can be found in the ECMAScript specification.

njs and nginx objects, modules, and Buffer

The objects, modules, and methods listed below are available with both the QuickJS and njs engines, unless noted otherwise.

• Buffer methods (0.4.4):
  • alloc, allocUnsafe, byteLength, compare, concat, from, isBuffer, isEncoding
• Buffer prototype methods (0.4.4):
  • compare, copy, equals, fill, includes, indexOf, lastIndexOf, readIntBE, readInt8, readInt16BE, readInt32BE, readIntLE, readInt16LE, readInt32LE, readUIntBE, readUInt8, readUInt16BE, readUInt32BE, readUIntLE, readUInt16LE, readUInt32LE, readDoubleBE, readDoubleLE, readFloatBE, readFloatLE, subarray, slice, swap16, swap32, swap64, toJSON, toString, write, writeIntBE, writeInt8, writeInt16BE, writeInt32BE, writeIntLE, writeInt16LE, writeInt32LE, writeUIntBE, writeUInt8, writeUInt16BE, writeUInt32BE, writeUIntLE, writeUInt16LE, writeUInt32LE, writeDoubleBE, writeDoubleLE, writeFloatBE, writeFloatLE
• Crypto methods (0.2.0): crypto.createHash, crypto.createHmac
• Query String methods (0.4.3): querystring.decode, querystring.encode, querystring.escape, querystring.parse, querystring.stringify, querystring.unescape
• TextDecoder methods (0.4.3): encoding, fatal, ignoreBOM, decode
• TextEncoder methods (0.4.3): encode, encodeInto
• XML methods (0.7.10): parse, xml.c14n, xml.exclusiveC14n
• zlib methods (0.7.12): deflateRawSync, deflateSync, inflateRawSync, inflateSync
• File system methods: fs.accessSync (0.3.9), fs.appendFileSync, fs.closeSync, fs.existsSync (0.8.2), fs.FileHandle (0.7.7), fs.fstatSync (0.7.7), fs.lstatSync (0.7.1), fs.mkdirSync (0.4.2), fs.openSync (0.7.7), fs.promises.open (0.7.7), fs.readdirSync (0.4.2), fs.readFileSync, fs.readSync (0.7.7), fs.realpathSync (0.3.9), fs.renameSync (0.3.4), fs.rmdirSync (0.4.2), fs.symlinkSync (0.3.9), fs.unlinkSync (0.3.9), fs.writeFileSync, fs.writeSync (0.7.7)
• fs.promises API (0.3.9), asynchronous version of file system methods.
• Global functions: atob, btoa (available with the njs engine since 0.7.6 and with the QuickJS engine since 1.0.1)
• clearTimeout and setTimeout functions (0.2.0)
• Global objects (0.3.3):
  • console (0.8.2): error, info, log, time, timeEnd, warn
  • crypto (0.7.0): getRandomValues, randomUUID (0.9.7), subtle.encrypt, subtle.decrypt, subtle.deriveBits, subtle.deriveKey, subtle.digest, subtle.exportKey (0.7.10), subtle.generateKey (0.7.10), subtle.importKey, subtle.sign, subtle.verify, subtle.wrapKey (0.9.7), subtle.unwrapKey (0.9.7)
  • globalThis alias (0.3.8)
  • njs: version, version_number (0.7.4), dump (njs engine only), memoryStats (0.7.8, njs engine only), on (0.5.2)
  • process: argv, env, pid, ppid
• nginx object methods:
  • HTTP Request: r.done (0.5.2), r.error, r.finish, r.internalRedirect, r.log, r.return (0.5.0), r.send (0.5.0), r.sendBuffer (0.5.2), r.sendHeader, r.setReturnValue (0.7.0), r.subrequest, r.warn
  • Stream Session: s.allow (0.2.4), s.decline (0.2.4), s.deny (0.2.4), s.done (0.2.4), s.error, s.log, s.off (0.2.4), s.on (0.2.4), s.send (0.2.4), s.sendDownstream (0.7.8), s.sendUpstream (0.7.8), s.setReturnValue (0.7.0), s.warn
  • Headers (0.5.1): append, delete, get, getAll, forEach, has, set
  • Request (0.7.10): arrayBuffer, headers, json, text
  • Response (0.5.1): arrayBuffer, headers, json, text
  • ngx (0.5.0): fetch (0.5.1), log
  • ngx.shared (0.8.0): add, clear, delete, freeSpace, get, has, incr, items, keys, pop, replace, set, size, ttl (0.9.7)
• nginx object properties:
  • HTTP Request: r.args, r.headersIn, r.headersOut, r.httpVersion, r.internal, r.jsVarNames (0.9.9), r.method, r.parent, r.readRequestArrayBuffer (0.9.9), r.readRequestForm (0.9.9), r.readRequestJSON (0.9.9), r.readRequestText (0.9.9), r.rawHeadersIn (0.4.1), r.rawHeadersOut (0.4.1), r.rawVariables (0.5.0), r.remoteAddress, r.requestBuffer (0.5.0), r.requestText, r.responseBuffer (0.5.0), r.responseText (0.5.0), r.status, r.uri, r.variables (0.2.8)
  • Stream Session: s.jsVarNames (0.9.9), s.remoteAddress, s.rawVariables (0.5.0), s.status (0.5.2), s.variables (0.2.8)
  • Periodic Session (0.8.1): PeriodicSession.rawVariables, PeriodicSession.variables
  • Request (0.7.10): bodyUsed, cache, credentials, method, mode, url
  • Response (0.5.1): bodyUsed, ok, redirected, status, statusText, type, url
  • ngx (0.5.0): build (0.8.0), conf_file_path (0.8.0), conf_prefix (0.7.8), error_log_path (0.8.0), prefix (0.8.0), version (0.8.0), version_number (0.8.0), worker_id (0.8.0)
  • ngx.shared (0.8.0): capacity, name, type

ECMAScript compliance (njs engine)

The ECMAScript language features listed below describe the njs engine, which is deprecated since 1.0.0. The QuickJS engine supports ES2023; new code should use the QuickJS engine instead.

The njs engine is implemented in compliance with ECMAScript 5.1 (strict mode) with some ECMAScript 6 and later extensions. The compliance is still evolving.

• Boolean values, numbers, strings, objects, arrays, functions, function constructors (0.3.6), and regular expressions
• ES5.1 operators, ES7 exponentiation operators, ES2020 optional chaining (0.9.6), ES2021 logical assignment operators ||=, &&=, ??= (0.9.6)
• ES5.1 statements: break, catch, continue, do while, else, finally, for, for in, if, return, switch, throw, try, var, while, labeled statements (0.2.8)
• ES6 statements: let (0.6.0), const (0.6.0), async (0.7.0), await (0.7.0)
• Math properties:
  • ES6: E, LN10, LN2, LOG10E, LOG2E, PI, SQRT1_2, SQRT2
• Math methods:
  • ES6: abs, acos, acosh, asin, asinh, atan, atan2, atanh, cbrt, ceil, clz32, cos, cosh, exp, expm1, floor, fround, hypot, imul, log, log10, log1p, log2, max, min, pow, random, round, sign, sin, sinh, sqrt, tan, tanh, trunc
• Number properties:
  • ES6: EPSILON, MAX_SAFE_INTEGER, MAX_VALUE, MIN_SAFE_INTEGER, MIN_VALUE, NEGATIVE_INFINITY, NaN, POSITIVE_INFINITY
• Number methods:
  • ES6: isFinite, isInteger, isNaN, isSafeInteger, parseFloat, parseInt
• Number prototype methods:
  • ES6: toExponential (0.3.6), toFixed (0.3.6), toPrecision (0.3.6)
• String methods:
  • ES5.1: fromCharCode
  • ES6: fromCodePoint
• String prototype methods:
  • ES5.1: charAt, concat, indexOf, lastIndexOf, match, replace, search, slice, split, substr, substring, toLowerCase, trim, toUpperCase
  • ES6: codePointAt, endsWith, includes, repeat, startsWith
  • ES8: padEnd, padStart
  • ES9: trimEnd (0.3.4), trimStart (0.3.4)
  • ES12: replaceAll (0.7.10)
• Object methods:
  • ES5.1: create (support without properties list), defineProperties (accessor descriptors support since 0.3.3), defineProperty (accessor descriptors support since 0.3.3), freeze, getOwnPropertyDescriptor, getOwnPropertyDescriptors (0.3.1), getOwnPropertyNames (0.3.1), getPrototypeOf, isExtensible, isFrozen, isSealed, keys, preventExtensions, seal
  • ES6: assign (0.3.7), is (0.3.8), setPrototypeOf (0.3.8)
  • ES8: entries (0.2.7), values (0.2.7)
• Object prototype methods:
  • ES5.1: hasOwnProperty, isPrototypeOf (0.3.0), propertyIsEnumerable, toString, valueOf
• Array methods:
  • ES5.1: isArray
  • ES6: of, from (0.8.0)
• Array prototype methods:
  • ES5.1: concat, every, filter, forEach, indexOf, join, lastIndexOf, map, pop, push, reduce, reduceRight, reverse, shift, slice, some, sort, splice, unshift
  • ES6: copyWithin (0.3.7), fill, find, findIndex
  • ES7: includes
  • ES2023: toReversed (0.8.0), toSorted (0.8.0), toSpliced (0.8.0)
• ArrayBuffer methods (0.3.8):
  • ES6: isView
• ArrayBuffer prototype methods (0.3.8):
  • ES6: slice
• Typed-array constructors (0.3.8):
  • ES6: Int8Array, Uint8Array, Uint8ClampedArray, Int16Array, Uint16Array, Int32Array, Uint32Array, Float32Array, Float64Array
• Typed-array prototype methods (0.3.8):
  • ES6: copyWithin, every (0.4.4), fill, filter (0.4.4), find (0.4.4), findIndex (0.4.4), forEach (0.4.4), includes (0.4.4), indexOf (0.4.4), join, lastIndexOf (0.4.4), map (0.4.4), reduce (0.4.4), reduceRight (0.4.4), reverse (0.4.4), set, slice, some (0.4.4), sort (0.4.2), subarray, toString
  • ES2023: toReversed (0.8.0), toSorted (0.8.0)
• Promise methods (0.3.8):
  • ES6: all (0.6.2), race (0.6.2), reject, resolve
  • ES2020: allSettled (0.6.2)
  • ES2021: any (0.6.2)
• Promise prototype methods (0.3.8):
  • ES6: catch, finally, then
• Function prototype methods:
  • ES5.1: apply, bind, call
• RegExp prototype accessor properties:
  • flags (0.6.0), global, ignoreCase, multiline, source, sticky (0.6.0)
• RegExp prototype methods:
  • [@@replace] (0.4.2), [@@split] (0.6.0)
  • ES5.1: exec, test, toString
• RegExp instance properties:
  • lastIndex
• RegExp ES9 named capture groups (0.3.2)
• DataView prototype methods (0.4.4):
  • ES6: getFloat32, getFloat64, getInt16, getInt32, getInt8, getUint16, getUint32, getUint8, setFloat32, setFloat64, setInt16, setInt32, setInt8, setUint16, setUint32, setUint8
• Date methods:
  • ES5.1: now, parse, UTC
• Date prototype methods:
  • ES5.1: getDate, getDay, getFullYear, getHours, getMilliseconds, getMinutes, getMonth, getSeconds, getTime, getTimezoneOffset, getUTCDate, getUTCDay, getUTCFullYear, getUTCHours, getUTCMilliseconds, getUTCMinutes, getUTCMonth, getUTCSeconds, toDateString, toISOString, toLocaleDateString, toLocaleString, toLocaleTimeString, toTimeString, toUTCString, setDate, setFullYear, setHours, setMinutes, setMilliseconds, setMonth, setSeconds, setTime, setUTCDate, setUTCFullYear, setUTCHours, setUTCMilliseconds, setUTCMinutes, setUTCMonth, setUTCSeconds
• JSON methods:
  • ES5.1: parse, stringify
• Symbol methods (0.7.6):
  • for, keyFor
• ES5.1 arguments object (0.2.5)
• ES6 rest parameters syntax (without destructuring support) (0.2.7)
• ES5.1 global functions: decodeURI, decodeURIComponent, encodeURI, encodeURIComponent, isFinite, isNaN, parseFloat, parseInt
• Error objects: Error, EvalError, InternalError, RangeError, ReferenceError, SyntaxError, TypeError, URIError
• ES6 modules support: default export and default import statements (0.3.0)
• ES6 arrow functions (0.3.1)
• Template literals: multiline strings, expression interpolation, nesting templates (0.3.2)