implemented basic client-server communication

node_modules/body-parser/lib/read.js

@@ -0,0 +1,205 @@
+/*!
+ * body-parser
+ * Copyright(c) 2014-2015 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ * @private
+ */
+
+var createError = require('http-errors')
+var destroy = require('destroy')
+var getBody = require('raw-body')
+var iconv = require('iconv-lite')
+var onFinished = require('on-finished')
+var unpipe = require('unpipe')
+var zlib = require('zlib')
+
+/**
+ * Module exports.
+ */
+
+module.exports = read
+
+/**
+ * Read a request into a buffer and parse.
+ *
+ * @param {object} req
+ * @param {object} res
+ * @param {function} next
+ * @param {function} parse
+ * @param {function} debug
+ * @param {object} options
+ * @private
+ */
+
+function read (req, res, next, parse, debug, options) {
+  var length
+  var opts = options
+  var stream
+
+  // flag as parsed
+  req._body = true
+
+  // read options
+  var encoding = opts.encoding !== null
+    ? opts.encoding
+    : null
+  var verify = opts.verify
+
+  try {
+    // get the content stream
+    stream = contentstream(req, debug, opts.inflate)
+    length = stream.length
+    stream.length = undefined
+  } catch (err) {
+    return next(err)
+  }
+
+  // set raw-body options
+  opts.length = length
+  opts.encoding = verify
+    ? null
+    : encoding
+
+  // assert charset is supported
+  if (opts.encoding === null && encoding !== null && !iconv.encodingExists(encoding)) {
+    return next(createError(415, 'unsupported charset "' + encoding.toUpperCase() + '"', {
+      charset: encoding.toLowerCase(),
+      type: 'charset.unsupported'
+    }))
+  }
+
+  // read body
+  debug('read body')
+  getBody(stream, opts, function (error, body) {
+    if (error) {
+      var _error
+
+      if (error.type === 'encoding.unsupported') {
+        // echo back charset
+        _error = createError(415, 'unsupported charset "' + encoding.toUpperCase() + '"', {
+          charset: encoding.toLowerCase(),
+          type: 'charset.unsupported'
+        })
+      } else {
+        // set status code on error
+        _error = createError(400, error)
+      }
+
+      // unpipe from stream and destroy
+      if (stream !== req) {
+        unpipe(req)
+        destroy(stream, true)
+      }
+
+      // read off entire request
+      dump(req, function onfinished () {
+        next(createError(400, _error))
+      })
+      return
+    }
+
+    // verify
+    if (verify) {
+      try {
+        debug('verify body')
+        verify(req, res, body, encoding)
+      } catch (err) {
+        next(createError(403, err, {
+          body: body,
+          type: err.type || 'entity.verify.failed'
+        }))
+        return
+      }
+    }
+
+    // parse
+    var str = body
+    try {
+      debug('parse body')
+      str = typeof body !== 'string' && encoding !== null
+        ? iconv.decode(body, encoding)
+        : body
+      req.body = parse(str)
+    } catch (err) {
+      next(createError(400, err, {
+        body: str,
+        type: err.type || 'entity.parse.failed'
+      }))
+      return
+    }
+
+    next()
+  })
+}
+
+/**
+ * Get the content stream of the request.
+ *
+ * @param {object} req
+ * @param {function} debug
+ * @param {boolean} [inflate=true]
+ * @return {object}
+ * @api private
+ */
+
+function contentstream (req, debug, inflate) {
+  var encoding = (req.headers['content-encoding'] || 'identity').toLowerCase()
+  var length = req.headers['content-length']
+  var stream
+
+  debug('content-encoding "%s"', encoding)
+
+  if (inflate === false && encoding !== 'identity') {
+    throw createError(415, 'content encoding unsupported', {
+      encoding: encoding,
+      type: 'encoding.unsupported'
+    })
+  }
+
+  switch (encoding) {
+    case 'deflate':
+      stream = zlib.createInflate()
+      debug('inflate body')
+      req.pipe(stream)
+      break
+    case 'gzip':
+      stream = zlib.createGunzip()
+      debug('gunzip body')
+      req.pipe(stream)
+      break
+    case 'identity':
+      stream = req
+      stream.length = length
+      break
+    default:
+      throw createError(415, 'unsupported content encoding "' + encoding + '"', {
+        encoding: encoding,
+        type: 'encoding.unsupported'
+      })
+  }
+
+  return stream
+}
+
+/**
+ * Dump the contents of a request.
+ *
+ * @param {object} req
+ * @param {function} callback
+ * @api private
+ */
+
+function dump (req, callback) {
+  if (onFinished.isFinished(req)) {
+    callback(null)
+  } else {
+    onFinished(req, callback)
+    req.resume()
+  }
+}

node_modules/body-parser/lib/types/json.js

@@ -0,0 +1,236 @@
+/*!
+ * body-parser
+ * Copyright(c) 2014 Jonathan Ong
+ * Copyright(c) 2014-2015 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ * @private
+ */
+
+var bytes = require('bytes')
+var contentType = require('content-type')
+var createError = require('http-errors')
+var debug = require('debug')('body-parser:json')
+var read = require('../read')
+var typeis = require('type-is')
+
+/**
+ * Module exports.
+ */
+
+module.exports = json
+
+/**
+ * RegExp to match the first non-space in a string.
+ *
+ * Allowed whitespace is defined in RFC 7159:
+ *
+ *    ws = *(
+ *            %x20 /              ; Space
+ *            %x09 /              ; Horizontal tab
+ *            %x0A /              ; Line feed or New line
+ *            %x0D )              ; Carriage return
+ */
+
+var FIRST_CHAR_REGEXP = /^[\x20\x09\x0a\x0d]*([^\x20\x09\x0a\x0d])/ // eslint-disable-line no-control-regex
+
+/**
+ * Create a middleware to parse JSON bodies.
+ *
+ * @param {object} [options]
+ * @return {function}
+ * @public
+ */
+
+function json (options) {
+  var opts = options || {}
+
+  var limit = typeof opts.limit !== 'number'
+    ? bytes.parse(opts.limit || '100kb')
+    : opts.limit
+  var inflate = opts.inflate !== false
+  var reviver = opts.reviver
+  var strict = opts.strict !== false
+  var type = opts.type || 'application/json'
+  var verify = opts.verify || false
+
+  if (verify !== false && typeof verify !== 'function') {
+    throw new TypeError('option verify must be function')
+  }
+
+  // create the appropriate type checking function
+  var shouldParse = typeof type !== 'function'
+    ? typeChecker(type)
+    : type
+
+  function parse (body) {
+    if (body.length === 0) {
+      // special-case empty json body, as it's a common client-side mistake
+      // TODO: maybe make this configurable or part of "strict" option
+      return {}
+    }
+
+    if (strict) {
+      var first = firstchar(body)
+
+      if (first !== '{' && first !== '[') {
+        debug('strict violation')
+        throw createStrictSyntaxError(body, first)
+      }
+    }
+
+    try {
+      debug('parse json')
+      return JSON.parse(body, reviver)
+    } catch (e) {
+      throw normalizeJsonSyntaxError(e, {
+        message: e.message,
+        stack: e.stack
+      })
+    }
+  }
+
+  return function jsonParser (req, res, next) {
+    if (req._body) {
+      debug('body already parsed')
+      next()
+      return
+    }
+
+    req.body = req.body || {}
+
+    // skip requests without bodies
+    if (!typeis.hasBody(req)) {
+      debug('skip empty body')
+      next()
+      return
+    }
+
+    debug('content-type %j', req.headers['content-type'])
+
+    // determine if request should be parsed
+    if (!shouldParse(req)) {
+      debug('skip parsing')
+      next()
+      return
+    }
+
+    // assert charset per RFC 7159 sec 8.1
+    var charset = getCharset(req) || 'utf-8'
+    if (charset.slice(0, 4) !== 'utf-') {
+      debug('invalid charset')
+      next(createError(415, 'unsupported charset "' + charset.toUpperCase() + '"', {
+        charset: charset,
+        type: 'charset.unsupported'
+      }))
+      return
+    }
+
+    // read
+    read(req, res, next, parse, debug, {
+      encoding: charset,
+      inflate: inflate,
+      limit: limit,
+      verify: verify
+    })
+  }
+}
+
+/**
+ * Create strict violation syntax error matching native error.
+ *
+ * @param {string} str
+ * @param {string} char
+ * @return {Error}
+ * @private
+ */
+
+function createStrictSyntaxError (str, char) {
+  var index = str.indexOf(char)
+  var partial = index !== -1
+    ? str.substring(0, index) + '#'
+    : ''
+
+  try {
+    JSON.parse(partial); /* istanbul ignore next */ throw new SyntaxError('strict violation')
+  } catch (e) {
+    return normalizeJsonSyntaxError(e, {
+      message: e.message.replace('#', char),
+      stack: e.stack
+    })
+  }
+}
+
+/**
+ * Get the first non-whitespace character in a string.
+ *
+ * @param {string} str
+ * @return {function}
+ * @private
+ */
+
+function firstchar (str) {
+  var match = FIRST_CHAR_REGEXP.exec(str)
+
+  return match
+    ? match[1]
+    : undefined
+}
+
+/**
+ * Get the charset of a request.
+ *
+ * @param {object} req
+ * @api private
+ */
+
+function getCharset (req) {
+  try {
+    return (contentType.parse(req).parameters.charset || '').toLowerCase()
+  } catch (e) {
+    return undefined
+  }
+}
+
+/**
+ * Normalize a SyntaxError for JSON.parse.
+ *
+ * @param {SyntaxError} error
+ * @param {object} obj
+ * @return {SyntaxError}
+ */
+
+function normalizeJsonSyntaxError (error, obj) {
+  var keys = Object.getOwnPropertyNames(error)
+
+  for (var i = 0; i < keys.length; i++) {
+    var key = keys[i]
+    if (key !== 'stack' && key !== 'message') {
+      delete error[key]
+    }
+  }
+
+  // replace stack before message for Node.js 0.10 and below
+  error.stack = obj.stack.replace(error.message, obj.message)
+  error.message = obj.message
+
+  return error
+}
+
+/**
+ * Get the simple type checker.
+ *
+ * @param {string} type
+ * @return {function}
+ */
+
+function typeChecker (type) {
+  return function checkType (req) {
+    return Boolean(typeis(req, type))
+  }
+}

node_modules/body-parser/lib/types/raw.js

@@ -0,0 +1,101 @@
+/*!
+ * body-parser
+ * Copyright(c) 2014-2015 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ */
+
+var bytes = require('bytes')
+var debug = require('debug')('body-parser:raw')
+var read = require('../read')
+var typeis = require('type-is')
+
+/**
+ * Module exports.
+ */
+
+module.exports = raw
+
+/**
+ * Create a middleware to parse raw bodies.
+ *
+ * @param {object} [options]
+ * @return {function}
+ * @api public
+ */
+
+function raw (options) {
+  var opts = options || {}
+
+  var inflate = opts.inflate !== false
+  var limit = typeof opts.limit !== 'number'
+    ? bytes.parse(opts.limit || '100kb')
+    : opts.limit
+  var type = opts.type || 'application/octet-stream'
+  var verify = opts.verify || false
+
+  if (verify !== false && typeof verify !== 'function') {
+    throw new TypeError('option verify must be function')
+  }
+
+  // create the appropriate type checking function
+  var shouldParse = typeof type !== 'function'
+    ? typeChecker(type)
+    : type
+
+  function parse (buf) {
+    return buf
+  }
+
+  return function rawParser (req, res, next) {
+    if (req._body) {
+      debug('body already parsed')
+      next()
+      return
+    }
+
+    req.body = req.body || {}
+
+    // skip requests without bodies
+    if (!typeis.hasBody(req)) {
+      debug('skip empty body')
+      next()
+      return
+    }
+
+    debug('content-type %j', req.headers['content-type'])
+
+    // determine if request should be parsed
+    if (!shouldParse(req)) {
+      debug('skip parsing')
+      next()
+      return
+    }
+
+    // read
+    read(req, res, next, parse, debug, {
+      encoding: null,
+      inflate: inflate,
+      limit: limit,
+      verify: verify
+    })
+  }
+}
+
+/**
+ * Get the simple type checker.
+ *
+ * @param {string} type
+ * @return {function}
+ */
+
+function typeChecker (type) {
+  return function checkType (req) {
+    return Boolean(typeis(req, type))
+  }
+}

node_modules/body-parser/lib/types/text.js

@@ -0,0 +1,121 @@
+/*!
+ * body-parser
+ * Copyright(c) 2014-2015 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ */
+
+var bytes = require('bytes')
+var contentType = require('content-type')
+var debug = require('debug')('body-parser:text')
+var read = require('../read')
+var typeis = require('type-is')
+
+/**
+ * Module exports.
+ */
+
+module.exports = text
+
+/**
+ * Create a middleware to parse text bodies.
+ *
+ * @param {object} [options]
+ * @return {function}
+ * @api public
+ */
+
+function text (options) {
+  var opts = options || {}
+
+  var defaultCharset = opts.defaultCharset || 'utf-8'
+  var inflate = opts.inflate !== false
+  var limit = typeof opts.limit !== 'number'
+    ? bytes.parse(opts.limit || '100kb')
+    : opts.limit
+  var type = opts.type || 'text/plain'
+  var verify = opts.verify || false
+
+  if (verify !== false && typeof verify !== 'function') {
+    throw new TypeError('option verify must be function')
+  }
+
+  // create the appropriate type checking function
+  var shouldParse = typeof type !== 'function'
+    ? typeChecker(type)
+    : type
+
+  function parse (buf) {
+    return buf
+  }
+
+  return function textParser (req, res, next) {
+    if (req._body) {
+      debug('body already parsed')
+      next()
+      return
+    }
+
+    req.body = req.body || {}
+
+    // skip requests without bodies
+    if (!typeis.hasBody(req)) {
+      debug('skip empty body')
+      next()
+      return
+    }
+
+    debug('content-type %j', req.headers['content-type'])
+
+    // determine if request should be parsed
+    if (!shouldParse(req)) {
+      debug('skip parsing')
+      next()
+      return
+    }
+
+    // get charset
+    var charset = getCharset(req) || defaultCharset
+
+    // read
+    read(req, res, next, parse, debug, {
+      encoding: charset,
+      inflate: inflate,
+      limit: limit,
+      verify: verify
+    })
+  }
+}
+
+/**
+ * Get the charset of a request.
+ *
+ * @param {object} req
+ * @api private
+ */
+
+function getCharset (req) {
+  try {
+    return (contentType.parse(req).parameters.charset || '').toLowerCase()
+  } catch (e) {
+    return undefined
+  }
+}
+
+/**
+ * Get the simple type checker.
+ *
+ * @param {string} type
+ * @return {function}
+ */
+
+function typeChecker (type) {
+  return function checkType (req) {
+    return Boolean(typeis(req, type))
+  }
+}

node_modules/body-parser/lib/types/urlencoded.js

@@ -0,0 +1,284 @@
+/*!
+ * body-parser
+ * Copyright(c) 2014 Jonathan Ong
+ * Copyright(c) 2014-2015 Douglas Christopher Wilson
+ * MIT Licensed
+ */
+
+'use strict'
+
+/**
+ * Module dependencies.
+ * @private
+ */
+
+var bytes = require('bytes')
+var contentType = require('content-type')
+var createError = require('http-errors')
+var debug = require('debug')('body-parser:urlencoded')
+var deprecate = require('depd')('body-parser')
+var read = require('../read')
+var typeis = require('type-is')
+
+/**
+ * Module exports.
+ */
+
+module.exports = urlencoded
+
+/**
+ * Cache of parser modules.
+ */
+
+var parsers = Object.create(null)
+
+/**
+ * Create a middleware to parse urlencoded bodies.
+ *
+ * @param {object} [options]
+ * @return {function}
+ * @public
+ */
+
+function urlencoded (options) {
+  var opts = options || {}
+
+  // notice because option default will flip in next major
+  if (opts.extended === undefined) {
+    deprecate('undefined extended: provide extended option')
+  }
+
+  var extended = opts.extended !== false
+  var inflate = opts.inflate !== false
+  var limit = typeof opts.limit !== 'number'
+    ? bytes.parse(opts.limit || '100kb')
+    : opts.limit
+  var type = opts.type || 'application/x-www-form-urlencoded'
+  var verify = opts.verify || false
+
+  if (verify !== false && typeof verify !== 'function') {
+    throw new TypeError('option verify must be function')
+  }
+
+  // create the appropriate query parser
+  var queryparse = extended
+    ? extendedparser(opts)
+    : simpleparser(opts)
+
+  // create the appropriate type checking function
+  var shouldParse = typeof type !== 'function'
+    ? typeChecker(type)
+    : type
+
+  function parse (body) {
+    return body.length
+      ? queryparse(body)
+      : {}
+  }
+
+  return function urlencodedParser (req, res, next) {
+    if (req._body) {
+      debug('body already parsed')
+      next()
+      return
+    }
+
+    req.body = req.body || {}
+
+    // skip requests without bodies
+    if (!typeis.hasBody(req)) {
+      debug('skip empty body')
+      next()
+      return
+    }
+
+    debug('content-type %j', req.headers['content-type'])
+
+    // determine if request should be parsed
+    if (!shouldParse(req)) {
+      debug('skip parsing')
+      next()
+      return
+    }
+
+    // assert charset
+    var charset = getCharset(req) || 'utf-8'
+    if (charset !== 'utf-8') {
+      debug('invalid charset')
+      next(createError(415, 'unsupported charset "' + charset.toUpperCase() + '"', {
+        charset: charset,
+        type: 'charset.unsupported'
+      }))
+      return
+    }
+
+    // read
+    read(req, res, next, parse, debug, {
+      debug: debug,
+      encoding: charset,
+      inflate: inflate,
+      limit: limit,
+      verify: verify
+    })
+  }
+}
+
+/**
+ * Get the extended query parser.
+ *
+ * @param {object} options
+ */
+
+function extendedparser (options) {
+  var parameterLimit = options.parameterLimit !== undefined
+    ? options.parameterLimit
+    : 1000
+  var parse = parser('qs')
+
+  if (isNaN(parameterLimit) || parameterLimit < 1) {
+    throw new TypeError('option parameterLimit must be a positive number')
+  }
+
+  if (isFinite(parameterLimit)) {
+    parameterLimit = parameterLimit | 0
+  }
+
+  return function queryparse (body) {
+    var paramCount = parameterCount(body, parameterLimit)
+
+    if (paramCount === undefined) {
+      debug('too many parameters')
+      throw createError(413, 'too many parameters', {
+        type: 'parameters.too.many'
+      })
+    }
+
+    var arrayLimit = Math.max(100, paramCount)
+
+    debug('parse extended urlencoding')
+    return parse(body, {
+      allowPrototypes: true,
+      arrayLimit: arrayLimit,
+      depth: Infinity,
+      parameterLimit: parameterLimit
+    })
+  }
+}
+
+/**
+ * Get the charset of a request.
+ *
+ * @param {object} req
+ * @api private
+ */
+
+function getCharset (req) {
+  try {
+    return (contentType.parse(req).parameters.charset || '').toLowerCase()
+  } catch (e) {
+    return undefined
+  }
+}
+
+/**
+ * Count the number of parameters, stopping once limit reached
+ *
+ * @param {string} body
+ * @param {number} limit
+ * @api private
+ */
+
+function parameterCount (body, limit) {
+  var count = 0
+  var index = 0
+
+  while ((index = body.indexOf('&', index)) !== -1) {
+    count++
+    index++
+
+    if (count === limit) {
+      return undefined
+    }
+  }
+
+  return count
+}
+
+/**
+ * Get parser for module name dynamically.
+ *
+ * @param {string} name
+ * @return {function}
+ * @api private
+ */
+
+function parser (name) {
+  var mod = parsers[name]
+
+  if (mod !== undefined) {
+    return mod.parse
+  }
+
+  // this uses a switch for static require analysis
+  switch (name) {
+    case 'qs':
+      mod = require('qs')
+      break
+    case 'querystring':
+      mod = require('querystring')
+      break
+  }
+
+  // store to prevent invoking require()
+  parsers[name] = mod
+
+  return mod.parse
+}
+
+/**
+ * Get the simple query parser.
+ *
+ * @param {object} options
+ */
+
+function simpleparser (options) {
+  var parameterLimit = options.parameterLimit !== undefined
+    ? options.parameterLimit
+    : 1000
+  var parse = parser('querystring')
+
+  if (isNaN(parameterLimit) || parameterLimit < 1) {
+    throw new TypeError('option parameterLimit must be a positive number')
+  }
+
+  if (isFinite(parameterLimit)) {
+    parameterLimit = parameterLimit | 0
+  }
+
+  return function queryparse (body) {
+    var paramCount = parameterCount(body, parameterLimit)
+
+    if (paramCount === undefined) {
+      debug('too many parameters')
+      throw createError(413, 'too many parameters', {
+        type: 'parameters.too.many'
+      })
+    }
+
+    debug('parse urlencoding')
+    return parse(body, undefined, undefined, { maxKeys: parameterLimit })
+  }
+}
+
+/**
+ * Get the simple type checker.
+ *
+ * @param {string} type
+ * @return {function}
+ */
+
+function typeChecker (type) {
+  return function checkType (req) {
+    return Boolean(typeis(req, type))
+  }
+}