🔥 write integer Query Parser. (#2306)

* Feature: write integer Query Parser.

* request changes on #2306 (comment)

* ref(test): separate test cases for QueryInt

ctx.go

@@ -1086,6 +1086,28 @@ func (c *Ctx) Query(key string, defaultValue ...string) string {
 	return defaultString(c.app.getString(c.fasthttp.QueryArgs().Peek(key)), defaultValue)
 }
 
+// QueryInt returns integer value of key string parameter in the url.
+// Default to empty or invalid key is 0.
+//
+//	GET /?name=alex&wanna_cake=2&id=
+//	QueryInt("wanna_cake", 1) == 2
+//	QueryInt("name", 1) == 1
+//	QueryInt("id", 1) == 1
+//	QueryInt("id") == 0
+func (c *Ctx) QueryInt(key string, defaultValue ...int) int {
+	// Use Atoi to convert the param to an int or return zero and an error
+	value, err := strconv.Atoi(c.app.getString(c.fasthttp.QueryArgs().Peek(key)))
+	if err != nil {
+		if len(defaultValue) > 0 {
+			return defaultValue[0]
+		} else {
+			return 0
+		}
+	}
+
+	return value
+}
+
 // QueryParser binds the query string to a struct.
 func (c *Ctx) QueryParser(out interface{}) error {
 	data := make(map[string][]string)

ctx_test.go

@@ -2115,12 +2115,27 @@ func Test_Ctx_Query(t *testing.T) {
 	app := New()
 	c := app.AcquireCtx(&fasthttp.RequestCtx{})
 	defer app.ReleaseCtx(c)
-	c.Request().URI().SetQueryString("search=john&age=20")
+	c.Request().URI().SetQueryString("search=john&age=20&id=")
 	utils.AssertEqual(t, "john", c.Query("search"))
 	utils.AssertEqual(t, "20", c.Query("age"))
 	utils.AssertEqual(t, "default", c.Query("unknown", "default"))
 }
 
+func Test_Ctx_QueryInt(t *testing.T) {
+	t.Parallel()
+	app := New()
+	c := app.AcquireCtx(&fasthttp.RequestCtx{})
+	defer app.ReleaseCtx(c)
+	c.Request().URI().SetQueryString("search=john&age=20&id=")
+
+	utils.AssertEqual(t, 0, c.QueryInt("foo"))
+	utils.AssertEqual(t, 20, c.QueryInt("age", 12))
+	utils.AssertEqual(t, 0, c.QueryInt("search"))
+	utils.AssertEqual(t, 1, c.QueryInt("search", 1))
+	utils.AssertEqual(t, 0, c.QueryInt("id"))
+	utils.AssertEqual(t, 2, c.QueryInt("id", 2))
+}
+
 // go test -run Test_Ctx_Range
 func Test_Ctx_Range(t *testing.T) {
 	t.Parallel()