Added functions to create generic servers and clients

5 files changed, 119 insertions, 63 deletions

diff --git a/src/node/index.js b/src/node/index.js
index ad3dd96af7..0b768edc6b 100644
--- a/src/node/index.js
+++ b/src/node/index.js
@@ -56,7 +56,7 @@ function loadObject(value) {
     });
     return result;
   } else if (value.className === 'Service') {
-    return client.makeClientConstructor(value);
+    return client.makeProtobufClientConstructor(value);
   } else if (value.className === 'Message' || value.className === 'Enum') {
     return value.build();
   } else {
@@ -119,7 +119,7 @@ exports.load = load;
 /**
  * See docs for server.makeServerConstructor
  */
-exports.buildServer = server.makeServerConstructor;
+exports.buildServer = server.makeProtobufServerConstructor;
 
 /**
  * Status name to code number mapping
@@ -141,3 +141,7 @@ exports.Credentials = grpc.Credentials;
 exports.ServerCredentials = grpc.ServerCredentials;
 
 exports.getGoogleAuthDelegate = getGoogleAuthDelegate;
+
+exports.makeGenericClientConstructor = client.makeClientConstructor;
+
+exports.makeGenericServerConstructor = server.makeServerConstructor;
diff --git a/src/node/src/client.js b/src/node/src/client.js
index 54b8dbdc9c..c46f7d0526 100644
--- a/src/node/src/client.js
+++ b/src/node/src/client.js
@@ -35,9 +35,6 @@
 
 var _ = require('underscore');
 
-var capitalize = require('underscore.string/capitalize');
-var decapitalize = require('underscore.string/decapitalize');
-
 var grpc = require('bindings')('grpc.node');
 
 var common = require('./common.js');
@@ -463,13 +460,18 @@ var requester_makers = {
 };
 
 /**
- * Creates a constructor for clients for the given service
- * @param {ProtoBuf.Reflect.Service} service The service to generate a client
- *     for
+ * Creates a constructor for a client with the given methods. The methods object
+ * maps method name to an object with the following keys:
+ * path: The path on the server for accessing the method. For example, for
+ *     protocol buffers, we use "/service_name/method_name"
+ * requestStream: bool indicating whether the client sends a stream
+ * resonseStream: bool indicating whether the server sends a stream
+ * requestSerialize: function to serialize request objects
+ * responseDeserialize: function to deserialize response objects
+ * @param {Object} methods An object mapping method names to method attributes
  * @return {function(string, Object)} New client constructor
  */
-function makeClientConstructor(service) {
-  var prefix = '/' + common.fullyQualifiedName(service) + '/';
+function makeClientConstructor(methods) {
   /**
    * Create a client with the given methods
    * @constructor
@@ -489,30 +491,41 @@ function makeClientConstructor(service) {
     this.channel = new grpc.Channel(address, options);
   }
 
-  _.each(service.children, function(method) {
+  _.each(methods, function(attrs, name) {
     var method_type;
-    if (method.requestStream) {
-      if (method.responseStream) {
+    if (attrs.requestStream) {
+      if (attrs.responseStream) {
         method_type = 'bidi';
       } else {
         method_type = 'client_stream';
       }
     } else {
-      if (method.responseStream) {
+      if (attrs.responseStream) {
         method_type = 'server_stream';
       } else {
         method_type = 'unary';
       }
     }
-    var serialize = common.serializeCls(method.resolvedRequestType.build());
-    var deserialize = common.deserializeCls(
-        method.resolvedResponseType.build());
-    Client.prototype[decapitalize(method.name)] = requester_makers[method_type](
-        prefix + capitalize(method.name), serialize, deserialize);
-    Client.prototype[decapitalize(method.name)].serialize = serialize;
-    Client.prototype[decapitalize(method.name)].deserialize = deserialize;
+    var serialize = attrs.requestSerialize;
+    var deserialize = attrs.responseDeserialize;
+    Client.prototype[name] = requester_makers[method_type](
+        attrs.path, serialize, deserialize);
+    Client.prototype[name].serialize = serialize;
+    Client.prototype[name].deserialize = deserialize;
   });
 
+  return Client;
+}
+
+/**
+ * Creates a constructor for clients for the given service
+ * @param {ProtoBuf.Reflect.Service} service The service to generate a client
+ *     for
+ * @return {function(string, Object)} New client constructor
+ */
+function makeProtobufClientConstructor(service) {
+  var method_attrs = common.getProtobufServiceAttrs(service);
+  var Client = makeClientConstructor(method_attrs);
   Client.service = service;
 
   return Client;
@@ -520,6 +533,8 @@ function makeClientConstructor(service) {
 
 exports.makeClientConstructor = makeClientConstructor;
 
+exports.makeProtobufClientConstructor = makeProtobufClientConstructor;
+
 /**
  * See docs for client.status
  */
diff --git a/src/node/src/common.js b/src/node/src/common.js
index eec8f0f987..55a6b13782 100644
--- a/src/node/src/common.js
+++ b/src/node/src/common.js
@@ -36,6 +36,7 @@
 var _ = require('underscore');
 
 var capitalize = require('underscore.string/capitalize');
+var decapitalize = require('underscore.string/decapitalize');
 
 /**
  * Get a function that deserializes a specific type of protobuf.
@@ -110,6 +111,26 @@ function wrapIgnoreNull(func) {
 }
 
 /**
+ * Return a map from method names to method attributes for the service.
+ * @param {ProtoBuf.Reflect.Service} service The service to get attributes for
+ * @return {Object} The attributes map
+ */
+function getProtobufServiceAttrs(service) {
+  var prefix = '/' + fullyQualifiedName(service) + '/';
+  return _.object(_.map(service.children, function(method) {
+    return [decapitalize(method.name), {
+      path: prefix + capitalize(method.name),
+      requestStream: method.requestStream,
+      responseStream: method.responseStream,
+      requestSerialize: serializeCls(method.resolvedRequestType.build()),
+      requestDeserialize: deserializeCls(method.resolvedRequestType.build()),
+      responseSerialize: serializeCls(method.resolvedResponseType.build()),
+      responseDeserialize: deserializeCls(method.resolvedResponseType.build())
+    }];
+  }));
+}
+
+/**
  * See docs for deserializeCls
  */
 exports.deserializeCls = deserializeCls;
@@ -128,3 +149,5 @@ exports.fullyQualifiedName = fullyQualifiedName;
  * See docs for wrapIgnoreNull
  */
 exports.wrapIgnoreNull = wrapIgnoreNull;
+
+exports.getProtobufServiceAttrs = getProtobufServiceAttrs;
diff --git a/src/node/src/server.js b/src/node/src/server.js
index b72d110666..e214d76dc5 100644
--- a/src/node/src/server.js
+++ b/src/node/src/server.js
@@ -35,9 +35,6 @@
 
 var _ = require('underscore');
 
-var capitalize = require('underscore.string/capitalize');
-var decapitalize = require('underscore.string/decapitalize');
-
 var grpc = require('bindings')('grpc.node');
 
 var common = require('./common');
@@ -532,26 +529,20 @@ Server.prototype.bind = function(port, creds) {
 };
 
 /**
- * Creates a constructor for servers with a service defined by the methods
- * object. The methods object has string keys and values of this form:
- * {serialize: function, deserialize: function, client_stream: bool,
- *  server_stream: bool}
- * @param {Object} methods Method descriptor for each method the server should
- *     expose
- * @param {string} prefix The prefex to prepend to each method name
- * @return {function(Object, Object)} New server constructor
+ * Create a constructor for servers with services defined by service_attr_map.
+ * That is an object that maps (namespaced) service names to objects that in
+ * turn map method names to objects with the following keys:
+ * path: The path on the server for accessing the method. For example, for
+ *     protocol buffers, we use "/service_name/method_name"
+ * requestStream: bool indicating whether the client sends a stream
+ * resonseStream: bool indicating whether the server sends a stream
+ * requestDeserialize: function to deserialize request objects
+ * responseSerialize: function to serialize response objects
+ * @param {Object} service_attr_map An object mapping service names to method
+ *     attribute map objects
+ * @return {function(Object, function, Object=)} New server constructor
  */
-function makeServerConstructor(services) {
-  var qual_names = [];
-  _.each(services, function(service) {
-    _.each(service.children, function(method) {
-      var name = common.fullyQualifiedName(method);
-      if (_.indexOf(qual_names, name) !== -1) {
-        throw new Error('Method ' + name + ' exposed by more than one service');
-      }
-      qual_names.push(name);
-    });
-  });
+function makeServerConstructor(service_attr_map) {
   /**
    * Create a server with the given handlers for all of the methods.
    * @constructor
@@ -565,41 +556,34 @@ function makeServerConstructor(services) {
   function SurfaceServer(service_handlers, getMetadata, options) {
     var server = new Server(getMetadata, options);
     this.inner_server = server;
-    _.each(services, function(service) {
-      var service_name = common.fullyQualifiedName(service);
+    _.each(service_attr_map, function(service_attrs, service_name) {
       if (service_handlers[service_name] === undefined) {
         throw new Error('Handlers for service ' +
             service_name + ' not provided.');
       }
-      var prefix = '/' + common.fullyQualifiedName(service) + '/';
-      _.each(service.children, function(method) {
+      _.each(service_attrs, function(attrs, name) {
         var method_type;
-        if (method.requestStream) {
-          if (method.responseStream) {
+        if (attrs.requestStream) {
+          if (attrs.responseStream) {
             method_type = 'bidi';
           } else {
             method_type = 'client_stream';
           }
         } else {
-          if (method.responseStream) {
+          if (attrs.responseStream) {
             method_type = 'server_stream';
           } else {
             method_type = 'unary';
           }
         }
-        if (service_handlers[service_name][decapitalize(method.name)] ===
-            undefined) {
-          throw new Error('Method handler for ' +
-              common.fullyQualifiedName(method) + ' not provided.');
+        if (service_handlers[service_name][name] === undefined) {
+          throw new Error('Method handler for ' + attrs.path +
+              ' not provided.');
         }
-        var serialize = common.serializeCls(
-            method.resolvedResponseType.build());
-        var deserialize = common.deserializeCls(
-            method.resolvedRequestType.build());
-        server.register(
-            prefix + capitalize(method.name),
-            service_handlers[service_name][decapitalize(method.name)],
-            serialize, deserialize, method_type);
+        var serialize = attrs.responseSerialize;
+        var deserialize = attrs.requestDeserialize;
+        server.register(attrs.path, service_handlers[service_name][name],
+                        serialize, deserialize, method_type);
       });
     }, this);
   }
@@ -636,6 +620,36 @@ function makeServerConstructor(services) {
 }
 
 /**
+ * Create a constructor for servers that serve the given services.
+ * @param {Array<ProtoBuf.Reflect.Service>} services The services that the
+ *     servers will serve
+ * @return {function(Object, function, Object=)} New server constructor
+ */
+function makeProtobufServerConstructor(services) {
+  var qual_names = [];
+  var service_attr_map = {};
+  _.each(services, function(service) {
+    var service_name = common.fullyQualifiedName(service);
+    _.each(service.children, function(method) {
+      var name = common.fullyQualifiedName(method);
+      if (_.indexOf(qual_names, name) !== -1) {
+        throw new Error('Method ' + name + ' exposed by more than one service');
+      }
+      qual_names.push(name);
+    });
+    var method_attrs = common.getProtobufServiceAttrs(service);
+    if (!service_attr_map.hasOwnProperty(service_name)) {
+      service_attr_map[service_name] = {};
+    }
+    service_attr_map[service_name] = _.extend(service_attr_map[service_name],
+                                              method_attrs);
+  });
+  return makeServerConstructor(service_attr_map);
+}
+
+/**
  * See documentation for makeServerConstructor
  */
 exports.makeServerConstructor = makeServerConstructor;
+
+exports.makeProtobufServerConstructor = makeProtobufServerConstructor;
diff --git a/src/node/test/surface_test.js b/src/node/test/surface_test.js
index 91d8197bee..6fae483e6c 100644
--- a/src/node/test/surface_test.js
+++ b/src/node/test/surface_test.js
@@ -89,7 +89,7 @@ describe('Cancelling surface client', function() {
       }
     });
     var port = server.bind('localhost:0');
-    var Client = surface_client.makeClientConstructor(mathService);
+    var Client = surface_client.makeProtobufClientConstructor(mathService);
     client = new Client('localhost:' + port);
   });
   after(function() {