Merge pull request #342 from ably/cloudflare-xhr

Disable upgrade to xhr_streaming if cloudflare headers detected
ably · Oct 21, 2016 · c8bb648 · c8bb648
2 parents 30041cd + 8dcfb40
commit c8bb648
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Showing 3 changed files with 33 additions and 7 deletions.
diff --git a/browser/lib/transport/xhrrequest.js b/browser/lib/transport/xhrrequest.js
@@ -30,8 +30,8 @@ var XHRRequest = (function() {
 		return isIE && (version = ieVersion()) && version === 10;
 	}
 
-	function getContentType(xhr) {
-		return xhr.getResponseHeader && xhr.getResponseHeader('content-type');
+	function getHeader(xhr, header) {
+		return xhr.getResponseHeader && xhr.getResponseHeader(header);
 	}
 
 	/* Safari mysteriously returns 'Identity' for transfer-encoding
@@ -158,8 +158,9 @@ var XHRRequest = (function() {
 
 		function onEnd() {
 			try {
-				var contentType = getContentType(xhr),
-					headers = null,
+				var contentType = getHeader(xhr, 'content-type'),
+					headers,
+					server,
 					json = contentType ? (contentType == 'application/json') : (xhr.responseType == 'text');
 
 				responseBody = json ? xhr.responseText : xhr.response;
@@ -178,6 +179,10 @@ var XHRRequest = (function() {
 					successResponse = (statusCode < 400);
 					headers = responseBody.headers;
 					responseBody = responseBody.response;
+				} else {
+					headers = {};
+					if(contentType) { headers['content-type'] = contentType };
+					if(server = getHeader(xhr, 'server')) { headers['server'] = server };
 				}
 			} catch(e) {
 				var err = new Error('Malformed response body from server: ' + e.message);
@@ -187,7 +192,7 @@ var XHRRequest = (function() {
 			}
 
 			if(successResponse) {
-				self.complete(null, responseBody, headers || (contentType && {'content-type': contentType}), unpacked);
+				self.complete(null, responseBody, headers, unpacked);
 				return;
 			}
 

diff --git a/common/lib/transport/comettransport.js b/common/lib/transport/comettransport.js
@@ -5,6 +5,20 @@ var CometTransport = (function() {
 		REQ_RECV_POLL = 2,
 		REQ_RECV_STREAM = 3;
 
+	function actOnConnectHeaders(headers, host, connectionManager) {
+		if(headers && headers.server && (headers.server.indexOf('cloudflare') > -1)) {
+			/* Cloudflare doesn't support xhr streaming */
+			var blacklist = connectionManager.transportHostBlacklist[host];
+			if(!blacklist) {
+				connectionManager.transportHostBlacklist[host] = ['xhr_streaming'];
+				return;
+			}
+			if(!Utils.arrIn(blacklist, 'xhr_streaming')) {
+				blacklist.push('xhr_streaming');
+			}
+		}
+	}
+
 	/*
 	 * A base comet transport class
 	 */
@@ -64,7 +78,8 @@ var CometTransport = (function() {
 				}
 				self.onData(data);
 			});
-			connectRequest.on('complete', function(err) {
+			connectRequest.on('complete', function(err, _body, headers) {
+				actOnConnectHeaders(headers, host, self.connectionManager);
 				if(!self.recvRequest) {
 					/* the transport was disposed before we connected */
 					err = err || new ErrorInfo('Request cancelled', 80000, 400);

diff --git a/common/lib/transport/connectionmanager.js b/common/lib/transport/connectionmanager.js
@@ -120,6 +120,8 @@ var ConnectionManager = (function() {
 		* transport, it'll just be that one. */
 		this.baseTransport = Utils.intersect(Defaults.transports, this.transports)[0];
 		this.upgradeTransports = Utils.intersect(this.transports, Defaults.upgradeTransports);
+		/* Map of hosts to an array of transports to not be tried for that host */
+		this.transportHostBlacklist = {};
 		this.transportPreference = null;
 
 		this.httpHosts = Defaults.getHosts(options);
@@ -218,8 +220,12 @@ var ConnectionManager = (function() {
 	 * @param callback
 	 */
 	ConnectionManager.prototype.tryATransport = function(transportParams, candidate, callback) {
-		var self = this;
+		var self = this, host = transportParams.host;
 		Logger.logAction(Logger.LOG_MICRO, 'ConnectionManager.tryATransport()', 'trying ' + candidate);
+		if((host in this.transportHostBlacklist) && Utils.arrIn(this.transportHostBlacklist[host], candidate)) {
+			Logger.logAction(Logger.LOG_MINOR, 'ConnectionManager.tryATransport()', candidate + ' transport is blacklisted for host ' + transportParams.host);
+			return;
+		}
 		(ConnectionManager.supportedTransports[candidate]).tryConnect(this, this.realtime.auth, transportParams, function(err, transport) {
 			var state = self.state;
 			if(state == self.states.closing || state == self.states.closed || state == self.states.failed) {