Create IMDB_GO_CLIENT.md

doc/IMDB_GO_CLIENT.md

+# How to use Go Client of Paddle Serving
+
+This document shows how to use Go as your client language. For Go client in Paddle Serving, a simple client package is provided https://github.com/PaddlePaddle/Serving/tree/develop/go/serving_client, a user can import this package as needed. Here is a simple example of sentiment analysis task based on IMDB dataset.
+
+### Install
+
+We suppose you have 1.9.2 or later version installed and python 2.7 version installed
+
+```shell
+go get github.com/PaddlePaddle/Serving/go/serving_client
+go get github.com/PaddlePaddle/Serving/go/proto
+pip install paddle-serving-server
+```
+
+### Download Text Classification Model
+
+``` shell
+wget https://paddle-serving.bj.bcebos.com/data%2Ftext_classification%2Fimdb_serving_example.tar.gz
+tar -xzf imdb_serving_example.tar.gz
+```
+
+### Server Side Code
+
+```python
+# test_server_go.py
+import os
+import sys
+from paddle_serving_server import OpMaker
+from paddle_serving_server import OpSeqMaker
+from paddle_serving_server import Server
+
+op_maker = OpMaker()
+read_op = op_maker.create('general_text_reader')
+general_infer_op = op_maker.create('general_text_infer')
+
+op_seq_maker = OpSeqMaker()
+op_seq_maker.add_op(read_op)
+op_seq_maker.add_op(general_infer_op)
+
+server = Server()
+server.set_op_sequence(op_seq_maker.get_op_sequence())
+server.load_model_config(sys.argv[1])
+server.prepare_server(workdir="work_dir1", port=9292, device="cpu")
+server.run_server()
+```
+
+### Start Server
+
+``` shell
+python test_server_go.py ./serving_server_model/ 9292
+```
+
+### Client code example
+
+``` go
+// imdb_client.go
+package main
+
+import (
+       "io"
+       "fmt"
+       "strings"
+       "bufio"
+       "strconv"
+       "os"
+       "serving_client"
+)
+
+func main() {
+     var config_file_path string
+     config_file_path = os.Args[1]
+     handle := serving_client.LoadModelConfig(config_file_path)
+     handle = serving_client.Connect("127.0.0.1", "9292", handle)
+
+     test_file_path := os.Args[2]
+     fi, err := os.Open(test_file_path)
+     if err != nil {
+     	fmt.Print(err)
+     }
+
+     defer fi.Close()
+     br := bufio.NewReader(fi)
+
+     fetch := []string{"cost", "acc", "prediction"}     
+
+     var result map[string][]float32
+
+     for {
+     	 line, err := br.ReadString('\n')
+	 		 if err == io.EOF {
+	       break
+	     }
+
+	 		 line = strings.Trim(line, "\n")
+
+	 		 var words = []int64{}
+
+	     s := strings.Split(line, " ")
+	     value, err := strconv.Atoi(s[0])
+	     var feed_int_map map[string][]int64
+       
+	     for _, v := range s[1:value + 1] {
+	       int_v, _ := strconv.Atoi(v)
+	       words = append(words, int64(int_v))
+	     }
+
+	     label, err := strconv.Atoi(s[len(s)-1])
+
+	     if err != nil {
+	       panic(err)
+	     }
+
+	     feed_int_map = map[string][]int64{}
+	     feed_int_map["words"] = words
+	     feed_int_map["label"] = []int64{int64(label)}
+	 
+	     result = serving_client.Predict(handle, feed_int_map, fetch)
+	     fmt.Println(result["prediction"][1], "\t", int64(label))
+    }
+}
+```
+
+### Prediction based on IMDB Test set
+
+``` python
+go run imdb_client.go serving_client_conf/serving_client_conf.stream.prototxt test.data > result
+```
+
+
+
+### Compute accuracy
+
+```python
+// acc.go
+package main
+
+import (
+       "io"
+       "os"
+       "fmt"
+       "bufio"
+       "strings"
+       "strconv"
+)
+
+func main() {
+     score_file := os.Args[1]
+     fi, err := os.Open(score_file)
+     if err != nil {
+     	fmt.Print(err)
+     }
+
+     defer fi.Close()
+     br := bufio.NewReader(fi)     
+    
+     total := int(0)
+     acc := int(0)
+     for {
+     	 line, err := br.ReadString('\n')
+     if err == io.EOF {
+        break
+     }
+    
+     line = strings.Trim(line, "\n")
+     s := strings.Split(line, "\t")
+     prob_str := strings.Trim(s[0], " ")
+     label_str := strings.Trim(s[1], " ")
+     prob, err := strconv.ParseFloat(prob_str, 32)
+     if err != nil {
+        panic(err)
+     }
+     label, err := strconv.ParseFloat(label_str, 32)
+     if err != nil {
+        panic(err)
+     }
+     if (prob - 0.5) * (label - 0.5) > 0 {
+        acc++
+     }
+     total++
+    }
+    fmt.Println("total num: ", total)
+    fmt.Println("acc num: ", acc)
+    fmt.Println("acc: ", float32(acc) / float32(total))    
+
+}
+```
+
+```
+go acc.go result
+```
+
+
+