Created writer mock.

Created mock server.
Added test for ping command plugin.

utils/mock.go

@@ -0,0 +1,51 @@
+package utils
+
+import (
+	"bytes"
+	"io"
+	"sync"
+)
+
+type CustomWriter struct {
+	Buf bytes.Buffer
+}
+
+func (cw *CustomWriter) Write(p []byte) (int, error) {
+	count := 0
+
+	for _, b := range p {
+		cw.Buf.WriteByte(b)
+		count += 1
+	}
+
+	if count != len(p) {
+		return count, io.ErrShortWrite
+	}
+
+	return count, nil
+}
+
+type MockData struct {
+	mu   sync.Mutex
+	data map[string]interface{}
+}
+
+type MockServer struct {
+	data MockData
+}
+
+func (server *MockServer) Lock() {
+	server.data.mu.Lock()
+}
+
+func (server *MockServer) Unlock() {
+	server.data.mu.Unlock()
+}
+
+func (server *MockServer) GetData(key string) interface{} {
+	return server.data.data[key]
+}
+
+func (server *MockServer) SetData(key string, value interface{}) {
+	server.data.data[key] = value
+}