michael@0: // Public API
michael@0: // ==========
michael@0: 
michael@0: // The main governing power behind the http2 API design is that it should look very similar to the
michael@0: // existing node.js [HTTPS API][1] (which is, in turn, almost identical to the [HTTP API][2]). The
michael@0: // additional features of HTTP/2 are exposed as extensions to this API. Furthermore, node-http2
michael@0: // should fall back to using HTTP/1.1 if needed. Compatibility with undocumented or deprecated
michael@0: // elements of the node.js HTTP/HTTPS API is a non-goal.
michael@0: //
michael@0: // Additional and modified API elements
michael@0: // ------------------------------------
michael@0: //
michael@0: // - **Class: http2.Endpoint**: an API for using the raw HTTP/2 framing layer. For documentation
michael@0: //   see the [lib/endpoint.js](endpoint.html) file.
michael@0: //
michael@0: // - **Class: http2.Server**
michael@0: //   - **Event: 'connection' (socket, [endpoint])**: there's a second argument if the negotiation of
michael@0: //     HTTP/2 was successful: the reference to the [Endpoint](endpoint.html) object tied to the
michael@0: //     socket.
michael@0: //
michael@0: // - **http2.createServer(options, [requestListener])**: additional option:
michael@0: //   - **log**: an optional [bunyan](https://github.com/trentm/node-bunyan) logger object
michael@0: //   - **plain**: if `true`, the server will accept HTTP/2 connections over plain TCP instead of
michael@0: //     TLS
michael@0: //
michael@0: // - **Class: http2.ServerResponse**
michael@0: //   - **response.push(options)**: initiates a server push. `options` describes the 'imaginary'
michael@0: //     request to which the push stream is a response; the possible options are identical to the
michael@0: //     ones accepted by `http2.request`. Returns a ServerResponse object that can be used to send
michael@0: //     the response headers and content.
michael@0: //
michael@0: // - **Class: http2.Agent**
michael@0: //   - **new Agent(options)**: additional option:
michael@0: //     - **log**: an optional [bunyan](https://github.com/trentm/node-bunyan) logger object
michael@0: //   - **agent.sockets**: only contains TCP sockets that corresponds to HTTP/1 requests.
michael@0: //   - **agent.endpoints**: contains [Endpoint](endpoint.html) objects for HTTP/2 connections.
michael@0: //
michael@0: // - **http2.request(options, [callback])**: additional option:
michael@0: //   - **plain**: if `true`, the client will not try to build a TLS tunnel, instead it will use
michael@0: //     the raw TCP stream for HTTP/2
michael@0: //
michael@0: // - **Class: http2.ClientRequest**
michael@0: //   - **Event: 'socket' (socket)**: in case of an HTTP/2 incoming message, `socket` is a reference
michael@0: //     to the associated [HTTP/2 Stream](stream.html) object (and not to the TCP socket).
michael@0: //   - **Event: 'push' (promise)**: signals the intention of a server push associated to this
michael@0: //     request. `promise` is an IncomingPromise. If there's no listener for this event, the server
michael@0: //     push is cancelled.
michael@0: //   - **request.setPriority(priority)**: assign a priority to this request. `priority` is a number
michael@0: //     between 0 (highest priority) and 2^31-1 (lowest priority). Default value is 2^30.
michael@0: //
michael@0: // - **Class: http2.IncomingMessage**
michael@0: //   - has two subclasses for easier interface description: **IncomingRequest** and
michael@0: //     **IncomingResponse**
michael@0: //   - **message.socket**: in case of an HTTP/2 incoming message, it's a reference to the associated
michael@0: //     [HTTP/2 Stream](stream.html) object (and not to the TCP socket).
michael@0: //
michael@0: // - **Class: http2.IncomingRequest (IncomingMessage)**
michael@0: //   - **message.url**: in case of an HTTP/2 incoming request, the `url` field always contains the
michael@0: //     path, and never a full url (it contains the path in most cases in the HTTPS api as well).
michael@0: //   - **message.scheme**: additional field. Mandatory HTTP/2 request metadata.
michael@0: //   - **message.host**: additional field. Mandatory HTTP/2 request metadata. Note that this
michael@0: //     replaces the old Host header field, but node-http2 will add Host to the `message.headers` for
michael@0: //     backwards compatibility.
michael@0: //
michael@0: // - **Class: http2.IncomingPromise (IncomingRequest)**
michael@0: //   - contains the metadata of the 'imaginary' request to which the server push is an answer.
michael@0: //   - **Event: 'response' (response)**: signals the arrival of the actual push stream. `response`
michael@0: //     is an IncomingResponse.
michael@0: //   - **Event: 'push' (promise)**: signals the intention of a server push associated to this
michael@0: //     request. `promise` is an IncomingPromise. If there's no listener for this event, the server
michael@0: //     push is cancelled.
michael@0: //   - **promise.cancel()**: cancels the promised server push.
michael@0: //   - **promise.setPriority(priority)**: assign a priority to this push stream. `priority` is a
michael@0: //     number between 0 (highest priority) and 2^31-1 (lowest priority). Default value is 2^30.
michael@0: //
michael@0: // API elements not yet implemented
michael@0: // --------------------------------
michael@0: //
michael@0: // - **Class: http2.Server**
michael@0: //   - **server.maxHeadersCount**
michael@0: //
michael@0: // API elements that are not applicable to HTTP/2
michael@0: // ----------------------------------------------
michael@0: //
michael@0: // The reason may be deprecation of certain HTTP/1.1 features, or that some API elements simply
michael@0: // don't make sense when using HTTP/2. These will not be present when a request is done with HTTP/2,
michael@0: // but will function normally when falling back to using HTTP/1.1.
michael@0: //
michael@0: // - **Class: http2.Server**
michael@0: //   - **Event: 'checkContinue'**: not in the spec, yet (see [http-spec#18][expect-continue])
michael@0: //   - **Event: 'upgrade'**: upgrade is deprecated in HTTP/2
michael@0: //   - **Event: 'timeout'**: HTTP/2 sockets won't timeout because of application level keepalive
michael@0: //     (PING frames)
michael@0: //   - **Event: 'connect'**: not in the spec, yet (see [http-spec#230][connect])
michael@0: //   - **server.setTimeout(msecs, [callback])**
michael@0: //   - **server.timeout**
michael@0: //
michael@0: // - **Class: http2.ServerResponse**
michael@0: //   - **Event: 'close'**
michael@0: //   - **Event: 'timeout'**
michael@0: //   - **response.writeContinue()**
michael@0: //   - **response.writeHead(statusCode, [reasonPhrase], [headers])**: reasonPhrase will always be
michael@0: //     ignored since [it's not supported in HTTP/2][3]
michael@0: //   - **response.setTimeout(timeout, [callback])**
michael@0: //
michael@0: // - **Class: http2.Agent**
michael@0: //   - **agent.maxSockets**: only affects HTTP/1 connection pool. When using HTTP/2, there's always
michael@0: //     one connection per host.
michael@0: //
michael@0: // - **Class: http2.ClientRequest**
michael@0: //   - **Event: 'upgrade'**
michael@0: //   - **Event: 'connect'**
michael@0: //   - **Event: 'continue'**
michael@0: //   - **request.setTimeout(timeout, [callback])**
michael@0: //   - **request.setNoDelay([noDelay])**
michael@0: //   - **request.setSocketKeepAlive([enable], [initialDelay])**
michael@0: //
michael@0: // - **Class: http2.IncomingMessage**
michael@0: //   - **Event: 'close'**
michael@0: //   - **message.setTimeout(timeout, [callback])**
michael@0: //
michael@0: // [1]: http://nodejs.org/api/https.html
michael@0: // [2]: http://nodejs.org/api/http.html
michael@0: // [3]: http://tools.ietf.org/html/draft-ietf-httpbis-http2-10#section-8.1.3.2
michael@0: // [expect-continue]: https://github.com/http2/http2-spec/issues/18
michael@0: // [connect]: https://github.com/http2/http2-spec/issues/230
michael@0: 
michael@0: // Common server and client side code
michael@0: // ==================================
michael@0: 
michael@0: var net = require('net');
michael@0: var url = require('url');
michael@0: var util = require('util');
michael@0: var EventEmitter = require('events').EventEmitter;
michael@0: var PassThrough = require('stream').PassThrough;
michael@0: var Readable = require('stream').Readable;
michael@0: var Writable = require('stream').Writable;
michael@0: var Endpoint = require('http2-protocol').Endpoint;
michael@0: var implementedVersion = require('http2-protocol').ImplementedVersion;
michael@0: var http = require('http');
michael@0: var https = require('https');
michael@0: 
michael@0: exports.STATUS_CODES = http.STATUS_CODES;
michael@0: exports.IncomingMessage = IncomingMessage;
michael@0: exports.OutgoingMessage = OutgoingMessage;
michael@0: 
michael@0: var deprecatedHeaders = [
michael@0:   'connection',
michael@0:   'host',
michael@0:   'keep-alive',
michael@0:   'proxy-connection',
michael@0:   'te',
michael@0:   'transfer-encoding',
michael@0:   'upgrade'
michael@0: ];
michael@0: 
michael@0: // When doing NPN/ALPN negotiation, HTTP/1.1 is used as fallback
michael@0: var supportedProtocols = [implementedVersion, 'http/1.1', 'http/1.0'];
michael@0: 
michael@0: // Logging
michael@0: // -------
michael@0: 
michael@0: // Logger shim, used when no logger is provided by the user.
michael@0: function noop() {}
michael@0: var defaultLogger = {
michael@0:   fatal: noop,
michael@0:   error: noop,
michael@0:   warn : noop,
michael@0:   info : noop,
michael@0:   debug: noop,
michael@0:   trace: noop,
michael@0: 
michael@0:   child: function() { return this; }
michael@0: };
michael@0: 
michael@0: // Bunyan serializers exported by submodules that are worth adding when creating a logger.
michael@0: exports.serializers = require('http2-protocol').serializers;
michael@0: 
michael@0: // IncomingMessage class
michael@0: // ---------------------
michael@0: 
michael@0: function IncomingMessage(stream) {
michael@0:   // * This is basically a read-only wrapper for the [Stream](stream.html) class.
michael@0:   PassThrough.call(this);
michael@0:   stream.pipe(this);
michael@0:   this.socket = this.stream = stream;
michael@0: 
michael@0:   this._log = stream._log.child({ component: 'http' });
michael@0: 
michael@0:   // * HTTP/2.0 does not define a way to carry the version identifier that is included in the
michael@0:   //   HTTP/1.1 request/status line. Version is always 2.0.
michael@0:   this.httpVersion = '2.0';
michael@0:   this.httpVersionMajor = 2;
michael@0:   this.httpVersionMinor = 0;
michael@0: 
michael@0:   // * `this.headers` will store the regular headers (and none of the special colon headers)
michael@0:   this.headers = {};
michael@0:   this.trailers = undefined;
michael@0:   this._lastHeadersSeen = undefined;
michael@0: 
michael@0:   // * Other metadata is filled in when the headers arrive.
michael@0:   stream.once('headers', this._onHeaders.bind(this));
michael@0:   stream.once('end', this._onEnd.bind(this));
michael@0: }
michael@0: IncomingMessage.prototype = Object.create(PassThrough.prototype, { constructor: { value: IncomingMessage } });
michael@0: 
michael@0: // [Request Header Fields](http://tools.ietf.org/html/draft-ietf-httpbis-http2-10#section-8.1.3.1)
michael@0: // * `headers` argument: HTTP/2.0 request and response header fields carry information as a series
michael@0: //   of key-value pairs. This includes the target URI for the request, the status code for the
michael@0: //   response, as well as HTTP header fields.
michael@0: IncomingMessage.prototype._onHeaders = function _onHeaders(headers) {
michael@0:   // * An HTTP/2.0 request or response MUST NOT include any of the following header fields:
michael@0:   //   Connection, Host, Keep-Alive, Proxy-Connection, TE, Transfer-Encoding, and Upgrade. A server
michael@0:   //   MUST treat the presence of any of these header fields as a stream error of type
michael@0:   //   PROTOCOL_ERROR.
michael@0:   for (var i = 0; i < deprecatedHeaders.length; i++) {
michael@0:     var key = deprecatedHeaders[i];
michael@0:     if (key in headers) {
michael@0:       this._log.error({ key: key, value: headers[key] }, 'Deprecated header found');
michael@0:       this.stream.emit('error', 'PROTOCOL_ERROR');
michael@0:       return;
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // * Store the _regular_ headers in `this.headers`
michael@0:   for (var name in headers) {
michael@0:     if (name[0] !== ':') {
michael@0:       this.headers[name] = headers[name];
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   // * The last header block, if it's not the first, will represent the trailers
michael@0:   var self = this;
michael@0:   this.stream.on('headers', function(headers) {
michael@0:     self._lastHeadersSeen = headers;
michael@0:   });
michael@0: };
michael@0: 
michael@0: IncomingMessage.prototype._onEnd = function _onEnd() {
michael@0:   this.trailers = this._lastHeadersSeen;
michael@0: };
michael@0: 
michael@0: IncomingMessage.prototype.setTimeout = noop;
michael@0: 
michael@0: IncomingMessage.prototype._checkSpecialHeader = function _checkSpecialHeader(key, value) {
michael@0:   if ((typeof value !== 'string') || (value.length === 0)) {
michael@0:     this._log.error({ key: key, value: value }, 'Invalid or missing special header field');
michael@0:     this.stream.emit('error', 'PROTOCOL_ERROR');
michael@0:   }
michael@0: 
michael@0:   return value;
michael@0: }
michael@0: ;
michael@0: 
michael@0: // OutgoingMessage class
michael@0: // ---------------------
michael@0: 
michael@0: function OutgoingMessage() {
michael@0:   // * This is basically a read-only wrapper for the [Stream](stream.html) class.
michael@0:   Writable.call(this);
michael@0: 
michael@0:   this._headers = {};
michael@0:   this._trailers = undefined;
michael@0:   this.headersSent = false;
michael@0: 
michael@0:   this.on('finish', this._finish);
michael@0: }
michael@0: OutgoingMessage.prototype = Object.create(Writable.prototype, { constructor: { value: OutgoingMessage } });
michael@0: 
michael@0: OutgoingMessage.prototype._write = function _write(chunk, encoding, callback) {
michael@0:   if (this.stream) {
michael@0:     this.stream.write(chunk, encoding, callback);
michael@0:   } else {
michael@0:     this.once('socket', this._write.bind(this, chunk, encoding, callback));
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype._finish = function _finish() {
michael@0:   if (this.stream) {
michael@0:     if (this._trailers) {
michael@0:       if (this.request) {
michael@0:         this.request.addTrailers(this._trailers);
michael@0:       } else {
michael@0:         this.stream.headers(this._trailers);
michael@0:       }
michael@0:     }
michael@0:     this.stream.end();
michael@0:   } else {
michael@0:     this.once('socket', this._finish.bind(this));
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype.setHeader = function setHeader(name, value) {
michael@0:   if (this.headersSent) {
michael@0:     throw new Error('Can\'t set headers after they are sent.');
michael@0:   } else {
michael@0:     name = name.toLowerCase();
michael@0:     if (deprecatedHeaders.indexOf(name) !== -1) {
michael@0:       throw new Error('Cannot set deprecated header: ' + name);
michael@0:     }
michael@0:     this._headers[name] = value;
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype.removeHeader = function removeHeader(name) {
michael@0:   if (this.headersSent) {
michael@0:     throw new Error('Can\'t remove headers after they are sent.');
michael@0:   } else {
michael@0:     delete this._headers[name.toLowerCase()];
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype.getHeader = function getHeader(name) {
michael@0:   return this._headers[name.toLowerCase()];
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype.addTrailers = function addTrailers(trailers) {
michael@0:   this._trailers = trailers;
michael@0: };
michael@0: 
michael@0: OutgoingMessage.prototype.setTimeout = noop;
michael@0: 
michael@0: OutgoingMessage.prototype._checkSpecialHeader = IncomingMessage.prototype._checkSpecialHeader;
michael@0: 
michael@0: // Server side
michael@0: // ===========
michael@0: 
michael@0: exports.createServer = createServer;
michael@0: exports.Server = Server;
michael@0: exports.IncomingRequest = IncomingRequest;
michael@0: exports.OutgoingResponse = OutgoingResponse;
michael@0: exports.ServerResponse = OutgoingResponse; // for API compatibility
michael@0: 
michael@0: // Server class
michael@0: // ------------
michael@0: 
michael@0: function Server(options) {
michael@0:   options = util._extend({}, options);
michael@0: 
michael@0:   this._log = (options.log || defaultLogger).child({ component: 'http' });
michael@0:   this._settings = options.settings;
michael@0: 
michael@0:   var start = this._start.bind(this);
michael@0:   var fallback = this._fallback.bind(this);
michael@0: 
michael@0:   // HTTP2 over TLS (using NPN or ALPN)
michael@0:   if ((options.key && options.cert) || options.pfx) {
michael@0:     this._log.info('Creating HTTP/2 server over TLS');
michael@0:     this._mode = 'tls';
michael@0:     options.ALPNProtocols = supportedProtocols;
michael@0:     options.NPNProtocols = supportedProtocols;
michael@0:     this._server = https.createServer(options);
michael@0:     this._originalSocketListeners = this._server.listeners('secureConnection');
michael@0:     this._server.removeAllListeners('secureConnection');
michael@0:     this._server.on('secureConnection', function(socket) {
michael@0:       var negotiatedProtocol = socket.alpnProtocol || socket.npnProtocol;
michael@0:       if ((negotiatedProtocol === implementedVersion) && socket.servername) {
michael@0:         start(socket);
michael@0:       } else {
michael@0:         fallback(socket);
michael@0:       }
michael@0:     });
michael@0:     this._server.on('request', this.emit.bind(this, 'request'));
michael@0:   }
michael@0: 
michael@0:   // HTTP2 over plain TCP
michael@0:   else if (options.plain) {
michael@0:     this._log.info('Creating HTTP/2 server over plain TCP');
michael@0:     this._mode = 'plain';
michael@0:     this._server = net.createServer(start);
michael@0:   }
michael@0: 
michael@0:   // HTTP/2 with HTTP/1.1 upgrade
michael@0:   else {
michael@0:     this._log.error('Trying to create HTTP/2 server with Upgrade from HTTP/1.1');
michael@0:     throw new Error('HTTP1.1 -> HTTP2 upgrade is not yet supported. Please provide TLS keys.');
michael@0:   }
michael@0: 
michael@0:   this._server.on('close', this.emit.bind(this, 'close'));
michael@0: }
michael@0: Server.prototype = Object.create(EventEmitter.prototype, { constructor: { value: Server } });
michael@0: 
michael@0: // Starting HTTP/2
michael@0: Server.prototype._start = function _start(socket) {
michael@0:   var endpoint = new Endpoint(this._log, 'SERVER', this._settings);
michael@0: 
michael@0:   this._log.info({ e: endpoint,
michael@0:                    client: socket.remoteAddress + ':' + socket.remotePort,
michael@0:                    SNI: socket.servername
michael@0:                  }, 'New incoming HTTP/2 connection');
michael@0: 
michael@0:   endpoint.pipe(socket).pipe(endpoint);
michael@0: 
michael@0:   var self = this;
michael@0:   endpoint.on('stream', function _onStream(stream) {
michael@0:     var response = new OutgoingResponse(stream);
michael@0:     var request = new IncomingRequest(stream);
michael@0: 
michael@0:     request.once('ready', self.emit.bind(self, 'request', request, response));
michael@0:   });
michael@0: 
michael@0:   endpoint.on('error', this.emit.bind(this, 'clientError'));
michael@0:   socket.on('error', this.emit.bind(this, 'clientError'));
michael@0: 
michael@0:   this.emit('connection', socket, endpoint);
michael@0: };
michael@0: 
michael@0: Server.prototype._fallback = function _fallback(socket) {
michael@0:   var negotiatedProtocol = socket.alpnProtocol || socket.npnProtocol;
michael@0: 
michael@0:   this._log.info({ client: socket.remoteAddress + ':' + socket.remotePort,
michael@0:                    protocol: negotiatedProtocol,
michael@0:                    SNI: socket.servername
michael@0:                  }, 'Falling back to simple HTTPS');
michael@0: 
michael@0:   for (var i = 0; i < this._originalSocketListeners.length; i++) {
michael@0:     this._originalSocketListeners[i].call(this._server, socket);
michael@0:   }
michael@0: 
michael@0:   this.emit('connection', socket);
michael@0: };
michael@0: 
michael@0: // There are [3 possible signatures][1] of the `listen` function. Every arguments is forwarded to
michael@0: // the backing TCP or HTTPS server.
michael@0: // [1]: http://nodejs.org/api/http.html#http_server_listen_port_hostname_backlog_callback
michael@0: Server.prototype.listen = function listen(port, hostname) {
michael@0:   this._log.info({ on: ((typeof hostname === 'string') ? (hostname + ':' + port) : port) },
michael@0:                  'Listening for incoming connections');
michael@0:   this._server.listen.apply(this._server, arguments);
michael@0: };
michael@0: 
michael@0: Server.prototype.close = function close(callback) {
michael@0:   this._log.info('Closing server');
michael@0:   this._server.close(callback);
michael@0: };
michael@0: 
michael@0: Server.prototype.setTimeout = function setTimeout(timeout, callback) {
michael@0:   if (this._mode === 'tls') {
michael@0:     this._server.setTimeout(timeout, callback);
michael@0:   }
michael@0: };
michael@0: 
michael@0: Object.defineProperty(Server.prototype, 'timeout', {
michael@0:   get: function getTimeout() {
michael@0:     if (this._mode === 'tls') {
michael@0:       return this._server.timeout;
michael@0:     } else {
michael@0:       return undefined;
michael@0:     }
michael@0:   },
michael@0:   set: function setTimeout(timeout) {
michael@0:     if (this._mode === 'tls') {
michael@0:       this._server.timeout = timeout;
michael@0:     }
michael@0:   }
michael@0: });
michael@0: 
michael@0: // Overriding `EventEmitter`'s `on(event, listener)` method to forward certain subscriptions to
michael@0: // `server`.There are events on the `http.Server` class where it makes difference whether someone is
michael@0: // listening on the event or not. In these cases, we can not simply forward the events from the
michael@0: // `server` to `this` since that means a listener. Instead, we forward the subscriptions.
michael@0: Server.prototype.on = function on(event, listener) {
michael@0:   if ((event === 'upgrade') || (event === 'timeout')) {
michael@0:     this._server.on(event, listener && listener.bind(this));
michael@0:   } else {
michael@0:     EventEmitter.prototype.on.call(this, event, listener);
michael@0:   }
michael@0: };
michael@0: 
michael@0: // `addContext` is used to add Server Name Indication contexts
michael@0: Server.prototype.addContext = function addContext(hostname, credentials) {
michael@0:   if (this._mode === 'tls') {
michael@0:     this._server.addContext(hostname, credentials);
michael@0:   }
michael@0: };
michael@0: 
michael@0: function createServer(options, requestListener) {
michael@0:   if (typeof options === 'function') {
michael@0:     requestListener = options;
michael@0:     options = undefined;
michael@0:   }
michael@0: 
michael@0:   var server = new Server(options);
michael@0: 
michael@0:   if (requestListener) {
michael@0:     server.on('request', requestListener);
michael@0:   }
michael@0: 
michael@0:   return server;
michael@0: }
michael@0: 
michael@0: // IncomingRequest class
michael@0: // ---------------------
michael@0: 
michael@0: function IncomingRequest(stream) {
michael@0:   IncomingMessage.call(this, stream);
michael@0: }
michael@0: IncomingRequest.prototype = Object.create(IncomingMessage.prototype, { constructor: { value: IncomingRequest } });
michael@0: 
michael@0: // [Request Header Fields](http://tools.ietf.org/html/draft-ietf-httpbis-http2-10#section-8.1.3.1)
michael@0: // * `headers` argument: HTTP/2.0 request and response header fields carry information as a series
michael@0: //   of key-value pairs. This includes the target URI for the request, the status code for the
michael@0: //   response, as well as HTTP header fields.
michael@0: IncomingRequest.prototype._onHeaders = function _onHeaders(headers) {
michael@0:   // * The ":method" header field includes the HTTP method
michael@0:   // * The ":scheme" header field includes the scheme portion of the target URI
michael@0:   // * The ":authority" header field includes the authority portion of the target URI
michael@0:   // * The ":path" header field includes the path and query parts of the target URI.
michael@0:   //   This field MUST NOT be empty; URIs that do not contain a path component MUST include a value
michael@0:   //   of '/', unless the request is an OPTIONS request for '*', in which case the ":path" header
michael@0:   //   field MUST include '*'.
michael@0:   // * All HTTP/2.0 requests MUST include exactly one valid value for all of these header fields. A
michael@0:   //   server MUST treat the absence of any of these header fields, presence of multiple values, or
michael@0:   //   an invalid value as a stream error of type PROTOCOL_ERROR.
michael@0:   this.method = this._checkSpecialHeader(':method'   , headers[':method']);
michael@0:   this.scheme = this._checkSpecialHeader(':scheme'   , headers[':scheme']);
michael@0:   this.host   = this._checkSpecialHeader(':authority', headers[':authority']  );
michael@0:   this.url    = this._checkSpecialHeader(':path'     , headers[':path']  );
michael@0: 
michael@0:   // * Host header is included in the headers object for backwards compatibility.
michael@0:   this.headers.host = this.host;
michael@0: 
michael@0:   // * Handling regular headers.
michael@0:   IncomingMessage.prototype._onHeaders.call(this, headers);
michael@0: 
michael@0:   // * Signaling that the headers arrived.
michael@0:   this._log.info({ method: this.method, scheme: this.scheme, host: this.host,
michael@0:                    path: this.url, headers: this.headers }, 'Incoming request');
michael@0:   this.emit('ready');
michael@0: };
michael@0: 
michael@0: // OutgoingResponse class
michael@0: // ----------------------
michael@0: 
michael@0: function OutgoingResponse(stream) {
michael@0:   OutgoingMessage.call(this);
michael@0: 
michael@0:   this._log = stream._log.child({ component: 'http' });
michael@0: 
michael@0:   this.stream = stream;
michael@0:   this.statusCode = 200;
michael@0:   this.sendDate = true;
michael@0: 
michael@0:   this.stream.once('headers', this._onRequestHeaders.bind(this));
michael@0: }
michael@0: OutgoingResponse.prototype = Object.create(OutgoingMessage.prototype, { constructor: { value: OutgoingResponse } });
michael@0: 
michael@0: OutgoingResponse.prototype.writeHead = function writeHead(statusCode, reasonPhrase, headers) {
michael@0:   if (typeof reasonPhrase === 'string') {
michael@0:     this._log.warn('Reason phrase argument was present but ignored by the writeHead method');
michael@0:   } else {
michael@0:     headers = reasonPhrase;
michael@0:   }
michael@0: 
michael@0:   for (var name in headers) {
michael@0:     this.setHeader(name, headers[name]);
michael@0:   }
michael@0:   headers = this._headers;
michael@0: 
michael@0:   if (this.sendDate && !('date' in this._headers)) {
michael@0:     headers.date = (new Date()).toUTCString();
michael@0:   }
michael@0: 
michael@0:   this._log.info({ status: statusCode, headers: this._headers }, 'Sending server response');
michael@0: 
michael@0:   headers[':status'] = this.statusCode = statusCode;
michael@0: 
michael@0:   this.stream.headers(headers);
michael@0:   this.headersSent = true;
michael@0: };
michael@0: 
michael@0: OutgoingResponse.prototype._implicitHeaders = function _implicitHeaders() {
michael@0:   if (!this.headersSent) {
michael@0:     this.writeHead(this.statusCode);
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingResponse.prototype.write = function write() {
michael@0:   this._implicitHeaders();
michael@0:   return OutgoingMessage.prototype.write.apply(this, arguments);
michael@0: };
michael@0: 
michael@0: OutgoingResponse.prototype.end = function end() {
michael@0:   this._implicitHeaders();
michael@0:   return OutgoingMessage.prototype.end.apply(this, arguments);
michael@0: };
michael@0: 
michael@0: OutgoingResponse.prototype._onRequestHeaders = function _onRequestHeaders(headers) {
michael@0:   this._requestHeaders = headers;
michael@0: };
michael@0: 
michael@0: OutgoingResponse.prototype.push = function push(options) {
michael@0:   if (typeof options === 'string') {
michael@0:     options = url.parse(options);
michael@0:   }
michael@0: 
michael@0:   if (!options.path) {
michael@0:     throw new Error('`path` option is mandatory.');
michael@0:   }
michael@0: 
michael@0:   var promise = util._extend({
michael@0:     ':method': (options.method || 'GET').toUpperCase(),
michael@0:     ':scheme': (options.protocol && options.protocol.slice(0, -1)) || this._requestHeaders[':scheme'],
michael@0:     ':authority': options.hostname || options.host || this._requestHeaders[':authority'],
michael@0:     ':path': options.path
michael@0:   }, options.headers);
michael@0: 
michael@0:   this._log.info({ method: promise[':method'], scheme: promise[':scheme'],
michael@0:                    authority: promise[':authority'], path: promise[':path'],
michael@0:                    headers: options.headers }, 'Promising push stream');
michael@0: 
michael@0:   var pushStream = this.stream.promise(promise);
michael@0: 
michael@0:   return new OutgoingResponse(pushStream);
michael@0: };
michael@0: 
michael@0: // Overriding `EventEmitter`'s `on(event, listener)` method to forward certain subscriptions to
michael@0: // `request`. See `Server.prototype.on` for explanation.
michael@0: OutgoingResponse.prototype.on = function on(event, listener) {
michael@0:   if (this.request && (event === 'timeout')) {
michael@0:     this.request.on(event, listener && listener.bind(this));
michael@0:   } else {
michael@0:     OutgoingMessage.prototype.on.call(this, event, listener);
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Client side
michael@0: // ===========
michael@0: 
michael@0: exports.ClientRequest = OutgoingRequest; // for API compatibility
michael@0: exports.OutgoingRequest = OutgoingRequest;
michael@0: exports.IncomingResponse = IncomingResponse;
michael@0: exports.Agent = Agent;
michael@0: exports.globalAgent = undefined;
michael@0: exports.request = function request(options, callback) {
michael@0:   return (options.agent || exports.globalAgent).request(options, callback);
michael@0: };
michael@0: exports.get = function get(options, callback) {
michael@0:   return (options.agent || exports.globalAgent).get(options, callback);
michael@0: };
michael@0: 
michael@0: // Agent class
michael@0: // -----------
michael@0: 
michael@0: function Agent(options) {
michael@0:   EventEmitter.call(this);
michael@0: 
michael@0:   options = util._extend({}, options);
michael@0: 
michael@0:   this._settings = options.settings;
michael@0:   this._log = (options.log || defaultLogger).child({ component: 'http' });
michael@0:   this.endpoints = {};
michael@0: 
michael@0:   // * Using an own HTTPS agent, because the global agent does not look at `NPN/ALPNProtocols` when
michael@0:   //   generating the key identifying the connection, so we may get useless non-negotiated TLS
michael@0:   //   channels even if we ask for a negotiated one. This agent will contain only negotiated
michael@0:   //   channels.
michael@0:   var agentOptions = {};
michael@0:   agentOptions.ALPNProtocols = supportedProtocols;
michael@0:   agentOptions.NPNProtocols = supportedProtocols;
michael@0:   this._httpsAgent = new https.Agent(agentOptions);
michael@0: 
michael@0:   this.sockets = this._httpsAgent.sockets;
michael@0:   this.requests = this._httpsAgent.requests;
michael@0: }
michael@0: Agent.prototype = Object.create(EventEmitter.prototype, { constructor: { value: Agent } });
michael@0: 
michael@0: Agent.prototype.request = function request(options, callback) {
michael@0:   if (typeof options === 'string') {
michael@0:     options = url.parse(options);
michael@0:   } else {
michael@0:     options = util._extend({}, options);
michael@0:   }
michael@0: 
michael@0:   options.method = (options.method || 'GET').toUpperCase();
michael@0:   options.protocol = options.protocol || 'https:';
michael@0:   options.host = options.hostname || options.host || 'localhost';
michael@0:   options.port = options.port || 443;
michael@0:   options.path = options.path || '/';
michael@0: 
michael@0:   if (!options.plain && options.protocol === 'http:') {
michael@0:     this._log.error('Trying to negotiate client request with Upgrade from HTTP/1.1');
michael@0:     throw new Error('HTTP1.1 -> HTTP2 upgrade is not yet supported.');
michael@0:   }
michael@0: 
michael@0:   var request = new OutgoingRequest(this._log);
michael@0: 
michael@0:   if (callback) {
michael@0:     request.on('response', callback);
michael@0:   }
michael@0: 
michael@0:   var key = [
michael@0:     !!options.plain,
michael@0:     options.host,
michael@0:     options.port
michael@0:   ].join(':');
michael@0: 
michael@0:   // * There's an existing HTTP/2 connection to this host
michael@0:   if (key in this.endpoints) {
michael@0:     var endpoint = this.endpoints[key];
michael@0:     request._start(endpoint.createStream(), options);
michael@0:   }
michael@0: 
michael@0:   // * HTTP/2 over plain TCP
michael@0:   else if (options.plain) {
michael@0:     endpoint = new Endpoint(this._log, 'CLIENT', this._settings);
michael@0:     endpoint.socket = net.connect({
michael@0:       host: options.host,
michael@0:       port: options.port,
michael@0:       localAddress: options.localAddress
michael@0:     });
michael@0:     endpoint.pipe(endpoint.socket).pipe(endpoint);
michael@0:     request._start(endpoint.createStream(), options);
michael@0:   }
michael@0: 
michael@0:   // * HTTP/2 over TLS negotiated using NPN or ALPN
michael@0:   else {
michael@0:     var started = false;
michael@0:     options.ALPNProtocols = supportedProtocols;
michael@0:     options.NPNProtocols = supportedProtocols;
michael@0:     options.servername = options.host; // Server Name Indication
michael@0:     options.agent = this._httpsAgent;
michael@0:     var httpsRequest = https.request(options);
michael@0: 
michael@0:     httpsRequest.on('socket', function(socket) {
michael@0:       var negotiatedProtocol = socket.alpnProtocol || socket.npnProtocol;
michael@0:       if (negotiatedProtocol !== undefined) {
michael@0:         negotiated();
michael@0:       } else {
michael@0:         socket.on('secureConnect', negotiated);
michael@0:       }
michael@0:     });
michael@0: 
michael@0:     var self = this;
michael@0:     function negotiated() {
michael@0:       var endpoint;
michael@0:       var negotiatedProtocol = httpsRequest.socket.alpnProtocol || httpsRequest.socket.npnProtocol;
michael@0:       if (negotiatedProtocol === implementedVersion) {
michael@0:         httpsRequest.socket.emit('agentRemove');
michael@0:         unbundleSocket(httpsRequest.socket);
michael@0:         endpoint = new Endpoint(self._log, 'CLIENT', self._settings);
michael@0:         endpoint.socket = httpsRequest.socket;
michael@0:         endpoint.pipe(endpoint.socket).pipe(endpoint);
michael@0:       }
michael@0:       if (started) {
michael@0:         if (endpoint) {
michael@0:           endpoint.close();
michael@0:         } else {
michael@0:           httpsRequest.abort();
michael@0:         }
michael@0:       } else {
michael@0:         if (endpoint) {
michael@0:           self._log.info({ e: endpoint, server: options.host + ':' + options.port },
michael@0:                          'New outgoing HTTP/2 connection');
michael@0:           self.endpoints[key] = endpoint;
michael@0:           self.emit(key, endpoint);
michael@0:         } else {
michael@0:           self.emit(key, undefined);
michael@0:         }
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     this.once(key, function(endpoint) {
michael@0:       started = true;
michael@0:       if (endpoint) {
michael@0:         request._start(endpoint.createStream(), options);
michael@0:       } else {
michael@0:         request._fallback(httpsRequest);
michael@0:       }
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   return request;
michael@0: };
michael@0: 
michael@0: Agent.prototype.get = function get(options, callback) {
michael@0:   var request = this.request(options, callback);
michael@0:   request.end();
michael@0:   return request;
michael@0: };
michael@0: 
michael@0: function unbundleSocket(socket) {
michael@0:   socket.removeAllListeners('data');
michael@0:   socket.removeAllListeners('end');
michael@0:   socket.removeAllListeners('readable');
michael@0:   socket.removeAllListeners('close');
michael@0:   socket.removeAllListeners('error');
michael@0:   socket.unpipe();
michael@0:   delete socket.ondata;
michael@0:   delete socket.onend;
michael@0: }
michael@0: 
michael@0: Object.defineProperty(Agent.prototype, 'maxSockets', {
michael@0:   get: function getMaxSockets() {
michael@0:     return this._httpsAgent.maxSockets;
michael@0:   },
michael@0:   set: function setMaxSockets(value) {
michael@0:     this._httpsAgent.maxSockets = value;
michael@0:   }
michael@0: });
michael@0: 
michael@0: exports.globalAgent = new Agent();
michael@0: 
michael@0: // OutgoingRequest class
michael@0: // ---------------------
michael@0: 
michael@0: function OutgoingRequest() {
michael@0:   OutgoingMessage.call(this);
michael@0: 
michael@0:   this._log = undefined;
michael@0: 
michael@0:   this.stream = undefined;
michael@0: }
michael@0: OutgoingRequest.prototype = Object.create(OutgoingMessage.prototype, { constructor: { value: OutgoingRequest } });
michael@0: 
michael@0: OutgoingRequest.prototype._start = function _start(stream, options) {
michael@0:   this.stream = stream;
michael@0: 
michael@0:   this._log = stream._log.child({ component: 'http' });
michael@0: 
michael@0:   for (var key in options.headers) {
michael@0:     this.setHeader(key, options.headers[key]);
michael@0:   }
michael@0:   var headers = this._headers;
michael@0:   delete headers.host;
michael@0: 
michael@0:   if (options.auth) {
michael@0:     headers.authorization = 'Basic ' + new Buffer(options.auth).toString('base64');
michael@0:   }
michael@0: 
michael@0:   headers[':scheme'] = options.protocol.slice(0, -1);
michael@0:   headers[':method'] = options.method;
michael@0:   headers[':authority'] = options.host;
michael@0:   headers[':path'] = options.path;
michael@0: 
michael@0:   this._log.info({ scheme: headers[':scheme'], method: headers[':method'],
michael@0:                    authority: headers[':authority'], path: headers[':path'],
michael@0:                    headers: (options.headers || {}) }, 'Sending request');
michael@0:   this.stream.headers(headers);
michael@0:   this.headersSent = true;
michael@0: 
michael@0:   this.emit('socket', this.stream);
michael@0: 
michael@0:   var response = new IncomingResponse(this.stream);
michael@0:   response.once('ready', this.emit.bind(this, 'response', response));
michael@0: 
michael@0:   this.stream.on('promise', this._onPromise.bind(this));
michael@0: };
michael@0: 
michael@0: OutgoingRequest.prototype._fallback = function _fallback(request) {
michael@0:   request.on('response', this.emit.bind(this, 'response'));
michael@0:   this.stream = this.request = request;
michael@0:   this.emit('socket', this.socket);
michael@0: };
michael@0: 
michael@0: OutgoingRequest.prototype.setPriority = function setPriority(priority) {
michael@0:   if (this.stream) {
michael@0:     this.stream.priority(priority);
michael@0:   } else {
michael@0:     this.once('socket', this.setPriority.bind(this, priority));
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Overriding `EventEmitter`'s `on(event, listener)` method to forward certain subscriptions to
michael@0: // `request`. See `Server.prototype.on` for explanation.
michael@0: OutgoingRequest.prototype.on = function on(event, listener) {
michael@0:   if (this.request && (event === 'upgrade')) {
michael@0:     this.request.on(event, listener && listener.bind(this));
michael@0:   } else {
michael@0:     OutgoingMessage.prototype.on.call(this, event, listener);
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Methods only in fallback mode
michael@0: OutgoingRequest.prototype.setNoDelay = function setNoDelay(noDelay) {
michael@0:   if (this.request) {
michael@0:     this.request.setNoDelay(noDelay);
michael@0:   } else if (!this.stream) {
michael@0:     this.on('socket', this.setNoDelay.bind(this, noDelay));
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingRequest.prototype.setSocketKeepAlive = function setSocketKeepAlive(enable, initialDelay) {
michael@0:   if (this.request) {
michael@0:     this.request.setSocketKeepAlive(enable, initialDelay);
michael@0:   } else if (!this.stream) {
michael@0:     this.on('socket', this.setSocketKeepAlive.bind(this, enable, initialDelay));
michael@0:   }
michael@0: };
michael@0: 
michael@0: OutgoingRequest.prototype.setTimeout = function setTimeout(timeout, callback) {
michael@0:   if (this.request) {
michael@0:     this.request.setTimeout(timeout, callback);
michael@0:   } else if (!this.stream) {
michael@0:     this.on('socket', this.setTimeout.bind(this, timeout, callback));
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Aborting the request
michael@0: OutgoingRequest.prototype.abort = function abort() {
michael@0:   if (this.request) {
michael@0:     this.request.abort();
michael@0:   } else if (this.stream) {
michael@0:     this.stream.reset('CANCEL');
michael@0:   } else {
michael@0:     this.on('socket', this.abort.bind(this));
michael@0:   }
michael@0: };
michael@0: 
michael@0: // Receiving push promises
michael@0: OutgoingRequest.prototype._onPromise = function _onPromise(stream, headers) {
michael@0:   this._log.info({ push_stream: stream.id }, 'Receiving push promise');
michael@0: 
michael@0:   var promise = new IncomingPromise(stream, headers);
michael@0: 
michael@0:   if (this.listeners('push').length > 0) {
michael@0:     this.emit('push', promise);
michael@0:   } else {
michael@0:     promise.cancel();
michael@0:   }
michael@0: };
michael@0: 
michael@0: // IncomingResponse class
michael@0: // ----------------------
michael@0: 
michael@0: function IncomingResponse(stream) {
michael@0:   IncomingMessage.call(this, stream);
michael@0: }
michael@0: IncomingResponse.prototype = Object.create(IncomingMessage.prototype, { constructor: { value: IncomingResponse } });
michael@0: 
michael@0: // [Response Header Fields](http://tools.ietf.org/html/draft-ietf-httpbis-http2-10#section-8.1.3.2)
michael@0: // * `headers` argument: HTTP/2.0 request and response header fields carry information as a series
michael@0: //   of key-value pairs. This includes the target URI for the request, the status code for the
michael@0: //   response, as well as HTTP header fields.
michael@0: IncomingResponse.prototype._onHeaders = function _onHeaders(headers) {
michael@0:   // * A single ":status" header field is defined that carries the HTTP status code field. This
michael@0:   //   header field MUST be included in all responses.
michael@0:   // * A client MUST treat the absence of the ":status" header field, the presence of multiple
michael@0:   //   values, or an invalid value as a stream error of type PROTOCOL_ERROR.
michael@0:   //   Note: currently, we do not enforce it strictly: we accept any format, and parse it as int
michael@0:   // * HTTP/2.0 does not define a way to carry the reason phrase that is included in an HTTP/1.1
michael@0:   //   status line.
michael@0:   this.statusCode = parseInt(this._checkSpecialHeader(':status', headers[':status']));
michael@0: 
michael@0:   // * Handling regular headers.
michael@0:   IncomingMessage.prototype._onHeaders.call(this, headers);
michael@0: 
michael@0:   // * Signaling that the headers arrived.
michael@0:   this._log.info({ status: this.statusCode, headers: this.headers}, 'Incoming response');
michael@0:   this.emit('ready');
michael@0: };
michael@0: 
michael@0: // IncomingPromise class
michael@0: // -------------------------
michael@0: 
michael@0: function IncomingPromise(responseStream, promiseHeaders) {
michael@0:   var stream = new Readable();
michael@0:   stream._read = noop;
michael@0:   stream.push(null);
michael@0:   stream._log = responseStream._log;
michael@0: 
michael@0:   IncomingRequest.call(this, stream);
michael@0: 
michael@0:   this._onHeaders(promiseHeaders);
michael@0: 
michael@0:   this._responseStream = responseStream;
michael@0: 
michael@0:   var response = new IncomingResponse(this._responseStream);
michael@0:   response.once('ready', this.emit.bind(this, 'response', response));
michael@0: 
michael@0:   this.stream.on('promise', this._onPromise.bind(this));
michael@0: }
michael@0: IncomingPromise.prototype = Object.create(IncomingRequest.prototype, { constructor: { value: IncomingPromise } });
michael@0: 
michael@0: IncomingPromise.prototype.cancel = function cancel() {
michael@0:   this._responseStream.reset('CANCEL');
michael@0: };
michael@0: 
michael@0: IncomingPromise.prototype.setPriority = function setPriority(priority) {
michael@0:   this._responseStream.priority(priority);
michael@0: };
michael@0: 
michael@0: IncomingPromise.prototype._onPromise = OutgoingRequest.prototype._onPromise;