Provide an API to dart:developer to control the web server hosting the Service Protocol

- [x] Add `ServiceProtocolnfo` class to dart:developer.
- [x] Add `Service` class to dart:developer.
- [x] Add `Service.getInfo` static method to dart:developer.
- [x] Add `Service.controlWebServer` static method to dart:developer.

API:

```dart

/// Information about the service protocol.
class ServiceProtocolInfo {
  /// The major version of the protocol.
  final int majorVersion;
  /// The minor version of the protocol.
  final int minorVersion;
  /// The Uri to access the service. If the web server is not running, this
  /// will be null.
  final Uri serverUri;
}

/// Access information about the service protocol and control the web server.
class Service {
  /// Get information about the service protocol.
  static Future<ServiceProtocolInfo> getInfo();

  /// Control the web server that the service protocol is accessed through.
  static Future<ServiceProtocolInfo> controlWebServer({bool enable: false});
}
```

... and add a randomly generated authentication token path prefix that must be passed in to access the service protocol.

Old base url:

Observatory listening on http://127.0.0.1:54804/

New base url:

Observatory listening on http://127.0.0.1:54804/<token>/

For example:

Observatory listening on http://127.0.0.1:54804/PTwjm8Ii8qg=/

Many tools will need to be updated.

Fixes #23320

BUG=
[email protected], [email protected]

Review URL: https://codereview.chromium.org/2438613002 .

Author: johnmccutchan

CHANGELOG.md

@@ -1,12 +1,16 @@
 ## 1.21.0
-### Core library changes
-
-* `dart:core`: `Set.difference` now takes a `Set<Object>` as argument.
 
 ### Language
 
 * Allow `=` as well as `:` as separator for named parameter default values.
 
+### Core library changes
+
+* `dart:core`: `Set.difference` now takes a `Set<Object>` as argument.
+
+* `dart:developer`:
+  * The service protocol http server can now be controlled from Dart code.
+
 ## 1.20.1 - 2016-10-13
 
 Patch release, resolves one issue:

runtime/bin/vmservice/server.dart

@@ -126,12 +126,23 @@ class Server {
   final bool _originCheckDisabled;
   HttpServer _server;
   bool get running => _server != null;
-  bool _displayMessages = false;
 
-  Server(this._service, this._ip, this._port, this._originCheckDisabled) {
-    _displayMessages = (_ip != '127.0.0.1' || _port != 8181);
+  /// Returns the server address including the auth token.
+  Uri get serverAddress {
+    if (!running) {
+      return null;
+    }
+    var ip = _server.address.address;
+    var port = _server.port;
+    if (useAuthToken) {
+      return Uri.parse('http://$ip:$port/$serviceAuthToken/');
+    } else {
+      return Uri.parse('http://$ip:$port/');
+    }
   }
 
+  Server(this._service, this._ip, this._port, this._originCheckDisabled);
+
   bool _isAllowedOrigin(String origin) {
     Uri uri;
     try {
@@ -179,6 +190,28 @@ class Server {
     return false;
   }
 
+  /// Checks the [requestUri] for the service auth token and returns the path.
+  /// If the service auth token check fails, returns null.
+  String _checkAuthTokenAndGetPath(Uri requestUri) {
+    if (!useAuthToken) {
+      return requestUri.path == '/' ? ROOT_REDIRECT_PATH : requestUri.path;
+    }
+    final List<String> requestPathSegments = requestUri.pathSegments;
+    if (requestPathSegments.length < 2) {
+      // Malformed.
+      return null;
+    }
+    // Check that we were given the auth token.
+    final String authToken = requestPathSegments[0];
+    if (authToken != serviceAuthToken) {
+      // Malformed.
+      return null;
+    }
+    // Construct the actual request path by chopping off the auth token.
+    return (requestPathSegments[1] == '') ?
+        ROOT_REDIRECT_PATH : '/${requestPathSegments.sublist(1).join('/')}';
+  }
+
   Future _requestHandler(HttpRequest request) async {
     if (!_originCheck(request)) {
       // This is a cross origin attempt to connect
@@ -231,8 +264,12 @@ class Server {
       return;
     }
 
-    final String path =
-          request.uri.path == '/' ? ROOT_REDIRECT_PATH : request.uri.path;
+    final String path = _checkAuthTokenAndGetPath(request.uri);
+    if (path == null) {
+      // Malformed.
+      request.response.close();
+      return;
+    }
 
     if (path == WEBSOCKET_PATH) {
       WebSocketTransformer.upgrade(request).then(
@@ -274,18 +311,14 @@ class Server {
     return HttpServer.bind(address, _port).then((s) {
       _server = s;
       _server.listen(_requestHandler, cancelOnError: true);
-      var ip = _server.address.address;
-      var port = _server.port;
-      if (_displayMessages) {
-        print('Observatory listening on http://$ip:$port');
-      }
+      print('Observatory listening on $serverAddress');
       // Server is up and running.
-      _notifyServerState(ip, _server.port);
-      onServerAddressChange('http://$ip:$port');
+      _notifyServerState(serverAddress.toString());
+      onServerAddressChange('$serverAddress');
       return this;
     }).catchError((e, st) {
       print('Could not start Observatory HTTP server:\n$e\n$st\n');
-      _notifyServerState("", 0);
+      _notifyServerState("");
       onServerAddressChange(null);
       return this;
     });
@@ -304,30 +337,24 @@ class Server {
       return new Future.value(this);
     }
 
-    // Force displaying of status messages if we are forcibly shutdown.
-    _displayMessages = _displayMessages || forced;
-
     // Shutdown HTTP server and subscription.
-    var ip = _server.address.address.toString();
-    var port = _server.port.toString();
+    String oldServerAddress = serverAddress;
     return cleanup(forced).then((_) {
-      if (_displayMessages) {
-        print('Observatory no longer listening on http://$ip:$port');
-      }
+      print('Observatory no longer listening on $oldServerAddress');
       _server = null;
-      _notifyServerState("", 0);
+      _notifyServerState("");
       onServerAddressChange(null);
       return this;
     }).catchError((e, st) {
       _server = null;
       print('Could not shutdown Observatory HTTP server:\n$e\n$st\n');
-      _notifyServerState("", 0);
+      _notifyServerState("");
       onServerAddressChange(null);
       return this;
     });
   }
 
 }
 
-void _notifyServerState(String ip, int port)
+void _notifyServerState(String uri)
     native "VMServiceIO_NotifyServerState";

runtime/bin/vmservice/vmservice_io.dart

@@ -162,6 +162,27 @@ Future<List<Map<String,String>>> listFilesCallback(Uri dirPath) async {
   return result;
 }
 
+Future<Uri> serverInformationCallback() async {
+  _lazyServerBoot();
+  return server.serverAddress;
+}
+
+Future<Uri> webServerControlCallback(bool enable) async {
+  _lazyServerBoot();
+  if (server.running == enable) {
+    // No change.
+    return server.serverAddress;
+  }
+
+  if (enable) {
+    await server.startup();
+    return server.serverAddress;
+  } else {
+    await server.shutdown(true);
+    return server.serverAddress;
+  }
+}
+
 _clearFuture(_) {
   serverFuture = null;
 }
@@ -204,6 +225,8 @@ main() {
   VMServiceEmbedderHooks.writeStreamFile = writeStreamFileCallback;
   VMServiceEmbedderHooks.readFile = readFileCallback;
   VMServiceEmbedderHooks.listFiles = listFilesCallback;
+  VMServiceEmbedderHooks.serverInformation = serverInformationCallback;
+  VMServiceEmbedderHooks.webServerControl = webServerControlCallback;
   // Always instantiate the vmservice object so that the exit message
   // can be delivered and waiting loaders can be cancelled.
   var service = new VMService();

runtime/bin/vmservice_dartium.cc

@@ -77,13 +77,8 @@ Dart_Isolate VmServiceServer::CreateIsolate(const uint8_t* snapshot_buffer) {
 }
 
 
-const char* VmServiceServer::GetServerIP() {
-  return VmService::GetServerIP();
-}
-
-
-intptr_t VmServiceServer::GetServerPort() {
-  return VmService::GetServerPort();
+const char* VmServiceServer::GetServerAddress() {
+  return VmService::GetServerAddress();
 }
 
 

runtime/bin/vmservice_dartium.h

@@ -18,8 +18,7 @@ class VmServiceServer {
   static void Bootstrap();
   static Dart_Isolate CreateIsolate(const uint8_t* snapshot_buffer);
 
-  static const char* GetServerIP();
-  static intptr_t GetServerPort();
+  static const char* GetServerAddress();
 
   static void DecompressAssets(const uint8_t* input, unsigned int input_len,
                                uint8_t** output, unsigned int* output_length);

runtime/bin/vmservice_impl.cc

@@ -91,27 +91,20 @@ class Resources {
 
 void NotifyServerState(Dart_NativeArguments args) {
   Dart_EnterScope();
-  const char* ip_chars;
-  Dart_Handle ip_arg = Dart_GetNativeArgument(args, 0);
-  if (Dart_IsError(ip_arg)) {
-    VmService::SetServerIPAndPort("", 0);
+  const char* uri_chars;
+  Dart_Handle uri_arg = Dart_GetNativeArgument(args, 0);
+  if (Dart_IsError(uri_arg)) {
+    VmService::SetServerAddress("");
     Dart_ExitScope();
     return;
   }
-  Dart_Handle result = Dart_StringToCString(ip_arg, &ip_chars);
+  Dart_Handle result = Dart_StringToCString(uri_arg, &uri_chars);
   if (Dart_IsError(result)) {
-    VmService::SetServerIPAndPort("", 0);
+    VmService::SetServerAddress("");
     Dart_ExitScope();
     return;
   }
-  Dart_Handle port_arg = Dart_GetNativeArgument(args, 1);
-  if (Dart_IsError(port_arg)) {
-    VmService::SetServerIPAndPort("", 0);
-    Dart_ExitScope();
-    return;
-  }
-  int64_t port = DartUtils::GetInt64ValueCheckRange(port_arg, 0, 65535);
-  VmService::SetServerIPAndPort(ip_chars, port);
+  VmService::SetServerAddress(uri_chars);
   Dart_ExitScope();
 }
 
@@ -129,7 +122,7 @@ struct VmServiceIONativeEntry {
 
 
 static VmServiceIONativeEntry _VmServiceIONativeEntries[] = {
-  {"VMServiceIO_NotifyServerState", 2, NotifyServerState},
+  {"VMServiceIO_NotifyServerState", 1, NotifyServerState},
   {"VMServiceIO_Shutdown", 0, Shutdown },
 };
 
@@ -156,8 +149,7 @@ static Dart_NativeFunction VmServiceIONativeResolver(Dart_Handle name,
 
 
 const char* VmService::error_msg_ = NULL;
-char VmService::server_ip_[kServerIpStringBufferSize];
-intptr_t VmService::server_port_ = 0;
+char VmService::server_uri_[kServerUriStringBufferSize];
 
 
 bool VmService::LoadForGenPrecompiled() {
@@ -180,7 +172,7 @@ bool VmService::Setup(const char* server_ip,
                       bool dev_mode_server) {
   Dart_Isolate isolate = Dart_CurrentIsolate();
   ASSERT(isolate != NULL);
-  SetServerIPAndPort("", 0);
+  SetServerAddress("");
 
   Dart_Handle result;
 
@@ -290,13 +282,16 @@ const char* VmService::GetErrorMessage() {
 }
 
 
-void VmService::SetServerIPAndPort(const char* ip, intptr_t port) {
-  if (ip == NULL) {
-    ip = "";
+void VmService::SetServerAddress(const char* server_uri) {
+  if (server_uri == NULL) {
+    server_uri = "";
+  }
+  const intptr_t server_uri_len = strlen(server_uri);
+  if (server_uri_len >= (kServerUriStringBufferSize - 1)) {
+    FATAL1("vm-service: Server URI exceeded length: %s\n", server_uri);
   }
-  strncpy(server_ip_, ip, kServerIpStringBufferSize);
-  server_ip_[kServerIpStringBufferSize - 1] = '\0';
-  server_port_ = port;
+  strncpy(server_uri_, server_uri, kServerUriStringBufferSize);
+  server_uri_[kServerUriStringBufferSize - 1] = '\0';
 }
 
 

runtime/bin/vmservice_impl.h

@@ -24,21 +24,16 @@ class VmService {
   // Error message if startup failed.
   static const char* GetErrorMessage();
 
-  // HTTP server's IP.
-  static const char* GetServerIP() {
-    return &server_ip_[0];
-  }
-
-  // HTTP server's port.
-  static intptr_t GetServerPort() {
-    return server_port_;
+  // HTTP Server's address.
+  static const char* GetServerAddress() {
+    return &server_uri_[0];
   }
 
  private:
-  static const intptr_t kServerIpStringBufferSize = 256;
+  static const intptr_t kServerUriStringBufferSize = 1024;
   friend void NotifyServerState(Dart_NativeArguments args);
 
-  static void SetServerIPAndPort(const char* ip, intptr_t port);
+  static void SetServerAddress(const char* server_uri_);
   static Dart_Handle GetSource(const char* name);
   static Dart_Handle LoadScript(const char* name);
   static Dart_Handle LoadLibrary(const char* name);
@@ -49,8 +44,7 @@ class VmService {
                                        Dart_Handle url);
 
   static const char* error_msg_;
-  static char server_ip_[kServerIpStringBufferSize];
-  static intptr_t server_port_;
+  static char server_uri_[kServerUriStringBufferSize];
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(VmService);