Handle DNS errors for existing hosts but wrong protocol (fixes #851) (#852)

* Handle DNS errors for existing hosts but wrong protocol (fixes #851)

* Bump version

* isDNSErr -> _isDNSErr

Author: inikulin

package.json

@@ -1,7 +1,7 @@
 {
   "name": "testcafe-hammerhead",
   "description": "A powerful web-proxy used as a core for the TestCafe testing framework (https://github.com/DevExpress/testcafe).",
-  "version": "9.3.8",
+  "version": "9.3.9",
   "homepage": "https://github.com/DevExpress/testcafe-hammerhead",
   "bugs": {
     "url": "https://github.com/DevExpress/testcafe-hammerhead/issues"

src/request-pipeline/destination-request/index.js

@@ -12,10 +12,6 @@ import { MESSAGE, getText } from '../../messages';
 // doesn't work (see: https://github.com/mikeal/request/issues/418).
 process.env.NODE_TLS_REJECT_UNAUTHORIZED = '0';
 
-// Utils
-function isDNSErr (err) {
-    return err.message && /ECONNREFUSED|ENOTFOUND/.test(err.message);
-}
 
 // DestinationRequest
 export default class DestinationRequest extends EventEmitter {
@@ -24,6 +20,7 @@ export default class DestinationRequest extends EventEmitter {
 
         this.req               = null;
         this.hasResponse       = false;
+        this.aborted           = false;
         this.opts              = opts;
         this.isHttps           = opts.protocol === 'https:';
         this.protocolInterface = this.isHttps ? https : http;
@@ -73,11 +70,21 @@ export default class DestinationRequest extends EventEmitter {
         }
     }
 
+    _abort () {
+        this.aborted = true;
+        this.req.abort();
+    }
+
+    _isDNSErr (err) {
+        return err.message && /ECONNREFUSED|ENOTFOUND/.test(err.message) ||
+               !this.aborted && !this.hasResponse && err.code && /ECONNRESET/.test(err.code);
+    }
+
     _onTimeout () {
         // NOTE: this handler is also called if we get an error response (for example, 404). So, we should check
         // for the response presence before raising the timeout error.
         if (!this.hasResponse) {
-            this.req.abort();
+            this._abort();
             this.emit('fatalError', getText(MESSAGE.destRequestTimeout, this.opts.url));
         }
     }
@@ -88,7 +95,7 @@ export default class DestinationRequest extends EventEmitter {
             this._send();
         }
 
-        else if (isDNSErr(err))
+        else if (this._isDNSErr(err))
             this.emit('fatalError', getText(MESSAGE.cantResolveUrl, this.opts.url));
         else
             this.emit('error');

test/server/proxy-test.js

@@ -301,6 +301,24 @@ describe('Proxy', function () {
             request(options);
         });
 
+        it('Should pass protocol DNS errors for existing host to session', function (done) {
+            session.handlePageError = function (ctx, err) {
+                expect(err).eql('Failed to find a DNS-record for the resource at <a href="https://127.0.0.1:2000">https://127.0.0.1:2000</a>.');
+                ctx.res.end();
+                done();
+                return true;
+            };
+
+            var options = {
+                url:     proxy.openSession('https://127.0.0.1:2000', session),
+                headers: {
+                    accept: 'text/html,application/xhtml+xml,application/xml;q=0.9,*!/!*;q=0.8'
+                }
+            };
+
+            request(options);
+        });
+
         it('Should pass service message processing to session', function (done) {
             var options = {
                 method: 'POST',