Add hello world http methode and test

server/plugin_test.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+	"io/ioutil"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestServeHTTP(t *testing.T) {
+	assert := assert.New(t)
+	plugin := Plugin{}
+	w := httptest.NewRecorder()
+	r := httptest.NewRequest("GET", "/", nil)
+
+	plugin.ServeHTTP(nil, w, r)
+
+	result := w.Result()
+	assert.NotNil(result)
+	bodyBytes, err := ioutil.ReadAll(result.Body)
+	assert.Nil(err)
+	bodyString := string(bodyBytes)
+
+	assert.Equal("Hello, world!", bodyString)
+}