Add GET /user/:userId/allowance/:allowanceId (#50)

Reviewed-on: #50

backend/api_test.go

@@ -421,6 +421,47 @@ func TestGetHistory(t *testing.T) {
 	response.Value(2).Object().Value("allowance").Number().IsEqual(-10)
 }
 
+func TestGetUserAllowanceById(t *testing.T) {
+	e := startServer(t)
+
+	// Create a new allowance
+	requestBody := map[string]interface{}{
+		"name":   TestAllowanceName,
+		"target": 5000,
+		"weight": 10,
+	}
+	resp := e.POST("/user/1/allowance").WithJSON(requestBody).Expect().Status(201).JSON().Object()
+	allowanceId := int(resp.Value("id").Number().Raw())
+
+	// Retrieve the created allowance by ID
+	result := e.GET("/user/1/allowance/" + strconv.Itoa(allowanceId)).Expect().Status(200).JSON().Object()
+	result.Value("id").IsEqual(allowanceId)
+	result.Value("name").IsEqual(TestAllowanceName)
+	result.Value("target").IsEqual(5000)
+	result.Value("weight").IsEqual(10)
+	result.Value("progress").IsEqual(0)
+}
+
+func TestGetUserByAllowanceIdInvalidAllowance(t *testing.T) {
+	e := startServer(t)
+	e.GET("/user/1/allowance/9999").Expect().Status(404)
+}
+
+func TestGetUserByAllowanceByIdInvalidUserId(t *testing.T) {
+	e := startServer(t)
+	e.GET("/user/999/allowance/1").Expect().Status(404)
+}
+
+func TestGetUserByAllowanceByIdBadUserId(t *testing.T) {
+	e := startServer(t)
+	e.GET("/user/bad/allowance/1").Expect().Status(400)
+}
+
+func TestGetUserByAllowanceByIdBadAllowanceId(t *testing.T) {
+	e := startServer(t)
+	e.GET("/user/1/allowance/bad").Expect().Status(400)
+}
+
 func getDelta(base time.Time, delta float64) (time.Time, time.Time) {
 	start := base.Add(-time.Duration(delta) * time.Second)
 	end := base.Add(time.Duration(delta) * time.Second)