make client to know the process ID of the server

core/general-client/include/general_model.h

@@ -53,10 +53,15 @@ class PredictorRes {
       const std::string& name) {
     return _float_map[name];
   }
+  void set_server_pid(int pid) { _server_pid = pid; }
+  int server_pid() { return _server_pid; }
 
  public:
   std::map<std::string, std::vector<std::vector<int64_t>>> _int64_map;
   std::map<std::string, std::vector<std::vector<float>>> _float_map;
+
+ private:
+  int _server_pid;
 };
 
 class PredictorClient {

core/general-client/src/general_model.cpp

@@ -237,6 +237,7 @@ int PredictorClient::predict(const std::vector<std::vector<float>> &float_feed,
       }
       postprocess_end = timeline.TimeStampUS();
     }
+    predict_res.set_server_pid(res.server_pid());
   }
 
   if (FLAGS_profile_client) {
@@ -400,6 +401,7 @@ int PredictorClient::batch_predict(
       }
     }
     postprocess_end = timeline.TimeStampUS();
+    predict_res_batch.set_server_pid(res.server_pid());
   }
 
   if (FLAGS_profile_client) {

core/general-client/src/pybind_general_model.cpp

@@ -39,7 +39,8 @@ PYBIND11_MODULE(serving_client, m) {
            [](PredictorRes &self, std::string &name) {
              return self.get_float_by_name(name);
            },
-           py::return_value_policy::reference);
+           py::return_value_policy::reference)
+      .def("server_pid", [](PredictorRes &self) { return self.server_pid(); });
 
   py::class_<PredictorClient>(m, "PredictorClient", py::buffer_protocol())
       .def(py::init())

core/general-server/op/general_response_op.cpp

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 #include "core/general-server/op/general_response_op.h"
+#include <unistd.h>
 #include <algorithm>
 #include <iostream>
 #include <memory>
@@ -74,6 +75,10 @@ int GeneralResponseOp::inference() {
   // response inst with only fetch_var_names
   Response *res = mutable_data<Response>();
 
+  // to let the client know which server the current response comes from
+  VLOG(2) << "getpid: " << getpid();
+  res->set_server_pid(static_cast<int>(getpid()));
+
   for (int i = 0; i < batch_size; ++i) {
     FetchInst *fetch_inst = res->add_insts();
     for (auto &idx : fetch_index) {

core/general-server/proto/general_model_service.proto

@@ -41,6 +41,7 @@ message Request {
 message Response {
   repeated FetchInst insts = 1;
   repeated int64 profile_time = 2;
+  optional int64 server_pid = 3;
 };
 
 service GeneralModelService {

core/sdk-cpp/proto/general_model_service.proto

@@ -41,6 +41,7 @@ message Request {
 message Response {
   repeated FetchInst insts = 1;
   repeated int64 profile_time = 2;
+  optional int64 server_pid = 3;
 };
 
 service GeneralModelService {

python/examples/fit_a_line/test_client.py

@@ -18,7 +18,8 @@ import sys
 
 client = Client()
 client.load_client_config(sys.argv[1])
-client.connect(["127.0.0.1:9393"])
+client.add_variant("var1", ["127.0.0.1:9393"], 50)
+client.connect()
 
 import paddle
 test_reader = paddle.batch(
@@ -27,5 +28,6 @@ test_reader = paddle.batch(
     batch_size=1)
 
 for data in test_reader():
-    fetch_map = client.predict(feed={"x": data[0][0]}, fetch=["price"])
-    print("{} {}".format(fetch_map["price"][0], data[0][1][0]))
+    [fetch_map, server_pid] = client.predict(
+        feed={"x": data[0][0]}, fetch=["price"], need_server_pid=True)
+    print("[{}] {} {}".format(server_pid, fetch_map["price"][0], data[0][1][0]))

python/paddle_serving_client/__init__.py

@@ -11,6 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+# pylint: disable=doc-string-missing
 
 import paddle_serving_client
 import os
@@ -27,10 +28,14 @@ float_type = 1
 class SDKConfig(object):
     def __init__(self):
         self.sdk_desc = sdk.SDKConf()
-        self.endpoints = []
+        self.tag_list = []
+        self.cluster_list = []
+        self.variant_weight_list = []
 
-    def set_server_endpoints(self, endpoints):
-        self.endpoints = endpoints
+    def add_server_variant(self, tag, cluster, variant_weight):
+        self.tag_list.append(tag)
+        self.cluster_list.append(cluster)
+        self.variant_weight_list.append(variant_weight)
 
     def gen_desc(self):
         predictor_desc = sdk.Predictor()
@@ -38,13 +43,14 @@ class SDKConfig(object):
         predictor_desc.service_name = \
             "baidu.paddle_serving.predictor.general_model.GeneralModelService"
         predictor_desc.endpoint_router = "WeightedRandomRender"
-        predictor_desc.weighted_random_render_conf.variant_weight_list = "100"
+        predictor_desc.weighted_random_render_conf.variant_weight_list = "|".join(
+            self.variant_weight_list)
 
+        for idx, tag in enumerate(self.tag_list):
             variant_desc = sdk.VariantConf()
-        variant_desc.tag = "var1"
-        variant_desc.naming_conf.cluster = "list://{}".format(":".join(
-            self.endpoints))
-
+            variant_desc.tag = tag
+            variant_desc.naming_conf.cluster = "list://{}".format(",".join(
+                self.cluster_list[idx]))
             predictor_desc.variants.extend([variant_desc])
 
         self.sdk_desc.predictors.extend([predictor_desc])
@@ -79,6 +85,7 @@ class Client(object):
         self.feed_names_to_idx_ = {}
         self.rpath()
         self.pid = os.getpid()
+        self.predictor_sdk_ = SDKConfig()
 
     def rpath(self):
         lib_path = os.path.dirname(paddle_serving_client.__file__)
@@ -130,13 +137,15 @@ class Client(object):
 
         return
 
-    def connect(self, endpoints):
+    def add_variant(self, tag, cluster, variant_weight):
+        self.predictor_sdk_.add_server_variant(tag, cluster,
+                                               str(variant_weight))
+
+    def connect(self):
         # check whether current endpoint is available
         # init from client config
         # create predictor here
-        predictor_sdk = SDKConfig()
-        predictor_sdk.set_server_endpoints(endpoints)
-        sdk_desc = predictor_sdk.gen_desc()
+        sdk_desc = self.predictor_sdk_.gen_desc()
         print(sdk_desc)
         self.client_handle_.create_predictor_by_desc(sdk_desc.SerializeToString(
         ))
@@ -155,7 +164,7 @@ class Client(object):
             raise SystemExit("The shape of feed tensor {} not match.".format(
                 key))
 
-    def predict(self, feed={}, fetch=[]):
+    def predict(self, feed={}, fetch=[], need_server_pid=False):
         int_slot = []
         float_slot = []
         int_feed_names = []
@@ -190,9 +199,10 @@ class Client(object):
                 result_map[name] = self.result_handle_.get_float_by_name(name)[
                     0]
 
-        return result_map
+        return [result_map, self.result_handle_.server_pid()
+                ] if need_server_pid else result_map
 
-    def batch_predict(self, feed_batch=[], fetch=[]):
+    def batch_predict(self, feed_batch=[], fetch=[], need_server_pid=False):
         int_slot_batch = []
         float_slot_batch = []
         int_feed_names = []
@@ -239,7 +249,8 @@ class Client(object):
                         index]
             result_map_batch.append(result_map)
 
-        return result_map_batch
+        return [result_map, self.result_handle_.server_pid()
+                ] if need_server_pid else result_map
 
     def release(self):
         self.client_handle_.destroy_predictor()