Added the ability for testrunner to start the HTTP server with a random port and communicate that p…

utils/testrunner/run_pipeline.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /** The default pipeline code for running a test file. */
 library pipeline;
 import 'dart:isolate';
 import 'dart:io';
+import 'dart:math';
 part 'pipeline_utils.dart';
 
 /**
  * The configuration passed in to the pipeline runner; this essentially
  * contains all the command line arguments passded to testrunner plus some
  * synthesized ones.
  */
 Map config;
 
 /** Paths to the various generated temporary files. */
@@ skipping 11 matching lines @@
 
 /** Path to the script file referenced from the HTML wrapper (Dart or JS). */
 String scriptFile = null;
 
 /** MIME type of the script. */
 String scriptType;
 
 /** Process id for the HTTP server. */
 int serverId;
 
+/** Port used by HTTP server. */
+int serverPort;
+
+/** Root directory for static files used by HTTP server. */
+String serverRoot;
+
+/** Path of the HTTP server script. */
+String serverPath;
+
+/** Number of attempts we will make to start the HTTP server. */
+const int MAX_SERVER_TRIES = 10;
+
+/** Amount of time we give the server to start, in msec. */
+const int SERVER_DELAY = 1000;
+
 void main() {
   port.receive((cfg, replyPort) {
     config = cfg;
     initPipeline(replyPort);
-    wrapStage();
+    startHTTPServerStage();
+  });
+}
+
+/** Initial pipeline stage - starts the HTTP server, if appropriate. */
+
+startHTTPServerStage() {
+  if (config["server"]) {
+    serverPath = config["testfile"];
+    // Replace .dart with _server.dart to get test's server file, if any.
+    var truncLen = serverPath.length - '.dart'.length;
+    serverPath = '${serverPath.substring(0, truncLen)}_server.dart';
+    var serverFile = new File(serverPath);
+    if (!serverFile.existsSync()) {
+      // No custom server; run the default server.
+      serverPath = '${config["runnerDir"]}/http_server_runner.dart';
+    }
+    if (serverPath != null) {
+      serverRoot = config["root"];
+      if (serverRoot == null) {
+        // Set the root to be the directory containing the test file.
+        serverRoot =  getDirectory(config["testfile"]);
+      }
+
+      if (config["port"] == null) {
+        // In this case we have to choose a random port and we need
+        // to see if the server starts successfully on that port.
+        var r = new Random();
+        tryStartHTTPServer(r, MAX_SERVER_TRIES);
+      } else {
+        serverPort = parseInt(config["port"]);
+        // Start the HTTP server.
+        serverId = startProcess(config["dart"],
+            [ serverPath, '--port=$serverPort', '--root=$serverRoot']);
+      }
+    }
+  }
+  wrapStage();
+}
+
+void tryStartHTTPServer(Random r, int remainingAttempts) {
+  // Pick a port from 1024 to 32767.
+  serverPort = 1024 + r.nextInt(32768-1024);

[Siggi Cherem (dart-lang), 2012/10/10 22:07:28]

nit: spaces around - 

[gram, 2012/10/10 23:36:04]

Done.

+  logMessage('Trying ${config["dart"]} $serverPath --port=$serverPort '
+      '--root=$serverRoot');
+  serverId = startProcess(config["dart"],
+      [ serverPath, '--port=$serverPort', '--root=$serverRoot']);
+  // Wait a second; if the process has exited try again with
+  // a different port, else go to next stage.
+  var t = new Timer(SERVER_DELAY, (t) {

[Siggi Cherem (dart-lang), 2012/10/10 22:07:28]

seems a bit brittle to wait 1 sec.

How about print something out from the subprocess so we can tell whether the
port was accepted? If the process exists before you get the print message, then
you try again?

[gram, 2012/10/10 23:36:04]

Done.

+    if (isProcessRunning(serverId)) {
+      wrapStage();
+    } else if (remainingAttempts == 0){

[Siggi Cherem (dart-lang), 2012/10/10 22:07:28]

nit: space before {

[gram, 2012/10/10 23:36:04]

Done.

[gram, 2012/10/10 23:36:04]

Done.

+      print('Failed to start HTTP server after numerous attempts; aborting.');
+      exit(1);
+    } else {
+      tryStartHTTPServer(r, remainingAttempts-1);

[Siggi Cherem (dart-lang), 2012/10/10 22:07:28]

nit: spaces

[gram, 2012/10/10 23:36:04]

Done.

[gram, 2012/10/10 23:36:04]

Done.

+    }
   });
 }
 
 /** Initial pipeline stage - generates Dart and HTML wrapper files. */
 wrapStage() {
   var tmpDir = config["tempdir"];
   var testFile = config["testfile"];
 
   // Make sure the temp dir exists.
   var d = new Directory(tmpDir);
@@ skipping 40 matching lines @@
       import 'dart:isolate';
       import '${config["unittest"]}' as unittest;
       import '${config["testfile"]}' as test;
       part '${config["runnerDir"]}/standard_test_runner.dart';
     ''';
     extras = '''
       includeFilters = ${config["include"]};
       excludeFilters = ${config["exclude"]};
       tprint = (msg) => print('###\$msg');
       notifyDone = (e) {};
+      unittest.testState["port"] = $serverPort;
     ''';
   } else {
     directives = '''
       import 'dart:html';
       import 'dart:isolate';
       import '${config["unittest"]}' as unittest;
       import '${config["testfile"]}' as test;
       part '${config["runnerDir"]}/standard_test_runner.dart';
     ''';
     extras = '''
       includeFilters = ${config["include"]};
       excludeFilters = ${config["exclude"]};
       tprint = (msg) => query('#console').addText('###\$msg\\n');
       notifyDone = (e) => window.postMessage('done', '*');
+      unittest.testState["port"] = $serverPort;
     ''';
   }
 
   var action = 'process(test.main, unittest.runTests)';
   if (config["layout-text"]) {
     action = 'runTextLayoutTests()';
   } else if (config["layout-pixel"]) {
     action = 'runPixelLayoutTests()';
   } else if (config["list-tests"]) {
     action = 'process(test.main, listTests)';
@@ skipping 33 matching lines @@
         import 'dart:isolate';
         import 'dart:html';
         import 'dart:uri';
         import '${config["unittest"]}' as 'unittest' ;
         import '$testFile', prefix: 'test' ;
         part '${config["runnerDir"]}/layout_test_runner.dart';
 
         main() {
           includeFilters = ${config["include"]};
           excludeFilters = ${config["exclude"]};
+          unittest.testState["port"] = $serverPort;
           runTests(test.main);
         }
     ''');
   }
 
-
   // Create the HTML wrapper and compile to Javascript if necessary.
   var isJavascript = config["runtime"] == 'drt-js';
   if (config["runtime"] == 'drt-dart' || isJavascript) {
     var bodyElements, runAsText;
 
     if (config["layout"]) {
       sourceFile = tempChildDartFile;
       scriptFile = isJavascript ? tempChildJsFile : tempChildDartFile;
       bodyElements = '';
     } else {
@@ skipping 56 matching lines @@
           [ '--out=$scriptFile', '$sourceFile' ]).
           then(runTestStage);
     }
   } else {
     runTestStage(0);
   }
 }
 
 /** Third stage of pipeline - runs the tests. */
 runTestStage(_) {
-  if (config["server"]) {
-    var serverPath = config["testfile"];
-    // Replace .dart with _server.dart to get test's server file, if any.
-    var truncLen = serverPath.length - '.dart'.length;
-    serverPath = '${serverPath.substring(0, truncLen)}_server.dart';
-    var serverFile = new File(serverPath);
-    if (!serverFile.existsSync()) {
-      // No custom server; run the default server.
-      serverPath = '${config["runnerDir"]}/http_server_runner.dart';
-    }
-    if (serverPath != null) {
-      var root = config["root"];
-      if (root == null) {
-        // Set the root to be the directory containing the test file.
-        root =  getDirectory(config["testfile"]);
-      }
-      // Start the HTTP server.
-      serverId = startProcess(config["dart"],
-          [ serverPath, '--port=${config["port"]}', '--root=$root']);
-    }
-  }
-
   var cmd, args;
   if (config["runtime"] == 'vm' || config["layout"]) { // Run the tests.
     if (config["checked"]) {
       cmd = config["dart"];
       args = [ '--enable_asserts', '--enable_type_checks', tempDartFile ];
     } else {
       cmd = config["dart"];
       args = [ tempDartFile ];
     }
   } else {
@@ skipping 14 matching lines @@
 
   if (!config["keep-files"]) { // Remove the temporary files.
     cleanup(tempDartFile);
     cleanup(tempHtmlFile);
     cleanup(tempJsFile);
     cleanup(tempChildDartFile);
     cleanup(tempChildJsFile);
   }
   completePipeline(exitcode);
 }