added test for index

.drone.yml

@@ -0,0 +1,15 @@
+kind: pipeline
+type: docker
+name: default
+
+steps:
+  - name: test
+    image: golang:1.14.4
+    commands:
+      - go build
+      - go test
+trigger:
+  branch:
+    - master
+  event:
+    - push

main_test.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestIndexHandler(t *testing.T) {
+	// TestIndexHandler tests the index
+	req, err := http.NewRequest("GET", "/", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	rr := httptest.NewRecorder()
+	handler := http.HandlerFunc(index)
+
+	handler.ServeHTTP(rr, req)
+
+	if status := rr.Code; status != http.StatusOK {
+		t.Errorf("Index returned wrong status code: got %v want %v",
+			status, http.StatusOK)
+	}
+
+	indexTemplate, err := ioutil.ReadFile("index.html")
+	if err != nil {
+		t.Fatal("Can't read index.html")
+	}
+
+	if rr.Body.String() != string(indexTemplate) {
+		t.Fatal("Index response is not the same as index.html")
+	}
+}