add initial test for main and index route

endpoints.go

+package main
+
+import (
+	"io"
+	"net/http"
+
+	_ "git.thevis.us/skepto/env"
+	_ "git.thevis.us/skepto/rex"
+)
+
+func Index(w http.ResponseWriter, r *http.Request) {
+    io.WriteString(w, "pehpeh-api")
+}

go.mod

 require (
 	git.thevis.us/skepto/env v0.0.0-20200712040037-f8a5c3d1b0fa
 	git.thevis.us/skepto/rex v0.10.0
+	github.com/gorilla/mux v1.7.4
+	github.com/stretchr/testify v1.2.2
 )

main.go

 package main
 
 import (
-	"io"
 	"net/http"
 
 	"git.thevis.us/skepto/env"
 	"git.thevis.us/skepto/rex"
 )
 
+type Server interface {
+	Run()
+
+	Get(pattern string, handler interface{})
+
+	ServeHTTP(w http.ResponseWriter, r *http.Request)
+}
+
 func main() {
+	srv := Configure()
+	srv.Run()
+}
+
+func Configure() Server {
 	env.Set("PORT", 7777)
 
-	app := rex.New()
-	app.Get("/", func(w http.ResponseWriter, r *http.Request) {
-		io.WriteString(w, "pehpeh-api")
-	})
-	app.Run()
+	server := rex.New()
+	server.Get("/", Index)
+	return server
 }

main_test.go

+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestConfigure(t *testing.T) {
+	srv := Configure()
+	request, _ := http.NewRequest("GET", "/", nil)
+	response := httptest.NewRecorder()
+	srv.ServeHTTP(response, request)
+	assert.Equal(t, "pehpeh-api", response.Body.String(), "response body is expected")
+	assert.Equal(t, 200, response.Code, "OK response is expected")
+}