add "unit test" for ReadQuestion

Author: chiaryan

apps/question-service/tests/read_test.go

@@ -0,0 +1,71 @@
+package tests
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"question-service/handlers"
+	"strings"
+	"testing"
+
+	"cloud.google.com/go/firestore"
+	firebase "firebase.google.com/go/v4"
+	"github.com/go-chi/chi/v5"
+	"github.com/joho/godotenv"
+	"google.golang.org/api/option"
+)
+
+func createService(t testing.TB) *handlers.Service {
+	err := godotenv.Load(filepath.Join("../", ".env"))
+	if err != nil {
+		log.Fatalf("Error loading .env file")
+	}
+
+	ctx := context.Background()
+	client, err := initFirestore(ctx)
+
+	if err != nil {
+		t.Fatalf("failed to initialize Firestore: %v", err)
+	}
+
+	return &handlers.Service{Client: client}
+}
+
+// initFirestore initializes the Firestore client
+func initFirestore(ctx context.Context) (*firestore.Client, error) {
+	credentialsPath := "../" + os.Getenv("FIREBASE_CREDENTIAL_PATH")
+	opt := option.WithCredentialsFile(credentialsPath)
+	app, err := firebase.NewApp(ctx, nil, opt)
+	if err != nil {
+		return nil, fmt.Errorf("failed to initialize Firebase App: %v", err)
+	}
+
+	client, err := app.Firestore(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get Firestore client: %v", err)
+	}
+	return client, nil
+}
+
+func Test_Read(t *testing.T) {
+	service := createService(t)
+	res := httptest.NewRecorder()
+
+	// adds chi context
+	// https://stackoverflow.com/questions/54580582/testing-chi-routes-w-path-variables
+	rctx := chi.NewRouteContext()
+	rctx.URLParams.Add("docRefID", "6SdbW4Awcfm5x0UQtWmg")
+
+	req := httptest.NewRequest(http.MethodGet, "http://localhost:8080/questions/6SdbW4Awcfm5x0UQtWmg", strings.NewReader(""))
+	req = req.WithContext(context.WithValue(req.Context(), chi.RouteCtxKey, rctx))
+
+	service.ReadQuestion(res, req)
+
+	if res.Result().StatusCode != 200 {
+		t.Fatalf("expected status code 200 but got %v", res.Result())
+	}
+}