Reuse http clients with the same configuration

cmd/http.go

@@ -16,7 +16,7 @@ var httpCmd = &cobra.Command{
 		plugin.Serve(&plugin.ServeConfig{
 			HandshakeConfig: dkplugin.Handshake,
 			Plugins: map[string]plugin.Plugin{
-				"executor": &dkplugin.ExecutorPlugin{Executor: &http.HTTP{}},
+				"executor": &dkplugin.ExecutorPlugin{Executor: http.New()},
 			},
 
 			// A non-nil value here enables gRPC serving for this plugin...

plugin/http/http.go

@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"log"
 	"net/http"
@@ -31,6 +32,14 @@ const (
 
 // HTTP process http request
 type HTTP struct {
+	clientPool map[string]http.Client
+}
+
+// New
+func New() *HTTP {
+	return &HTTP{
+		clientPool: make(map[string]http.Client),
+	}
 }
 
 // Execute Process method of the plugin
@@ -96,18 +105,31 @@ func (s *HTTP) ExecuteImpl(args *types.ExecuteRequest) ([]byte, error) {
 		log.Printf("request  %#v\n\n", req)
 	}
 
-	client, warns := createClient(args.Config)
-	for _, warn := range warns {
-		output.Write([]byte(fmt.Sprintf("Warning: %s.\n", warn.Error())))
+	// get client from pool
+	var (
+		client http.Client
+		ok     bool
+	)
+
+	cc := args.Config["timeout"] + args.Config["tlsRootCAsFile"] + args.Config["tlsCertificateFile"] + args.Config["tlsCertificateKeyFile"]
+
+	if client, ok = s.clientPool[cc]; !ok {
+		var warns []error
+		client, warns = createClient(args.Config)
+		for _, warn := range warns {
+			_, _ = output.Write([]byte(fmt.Sprintf("Warning: %s.\n", warn.Error())))
+		}
+		s.clientPool[cc] = client
 	}
 
+	// do request
 	resp, err := client.Do(req)
 	if err != nil {
 		return output.Bytes(), err
 	}
 
 	defer resp.Body.Close()
-	out, err := ioutil.ReadAll(resp.Body)
+	out, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return output.Bytes(), err
 	}

plugin/http/http_test.go

@@ -3,7 +3,7 @@ package http
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"net/http/httptest"
@@ -43,13 +43,13 @@ func newTestServer() *httptest.Server {
 		// Echo POST body back to request
 		case "/echo":
 			if r.Method == http.MethodPost {
-				in, err := ioutil.ReadAll(r.Body)
+				in, err := io.ReadAll(r.Body)
 				if err != nil {
 					w.WriteHeader(500)
 					return
 				}
 				r.Body.Close()
-				w.Write(in)
+				_, _ = w.Write(in)
 				w.WriteHeader(200)
 				return
 			}
@@ -81,7 +81,7 @@ func TestExecute(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			http := &HTTP{}
+			http := New()
 			pa := &types.ExecuteRequest{
 				JobName: tt.name,
 				Config:  tt.config,
@@ -113,7 +113,7 @@ func TestNoVerifyPeer(t *testing.T) {
 			"tlsNoVerifyPeer": "true",
 		},
 	}
-	http := &HTTP{}
+	http := New()
 	output, _ := http.Execute(pa, nil)
 	fmt.Println(string(output.Output))
 	fmt.Println(output.Error)
@@ -133,7 +133,7 @@ func TestClientSSLCert(t *testing.T) {
 			"tlsCertificateKeyFile": "testdata/badssl.com-client-key-decrypted.pem",
 		},
 	}
-	http := &HTTP{}
+	http := New()
 	output, _ := http.Execute(pa, nil)
 	fmt.Println(string(output.Output))
 	fmt.Println(output.Error)
@@ -152,7 +152,7 @@ func TestRootCA(t *testing.T) {
 			"tlsRootCAsFile": "testdata/badssl-ca-untrusted-root.crt",
 		},
 	}
-	http := &HTTP{}
+	http := New()
 	output, _ := http.Execute(pa, nil)
 	fmt.Println(string(output.Output))
 	fmt.Println(output.Error)