basic common app packages

request/query.go

@@ -0,0 +1,42 @@
+// Copyright 2024 Patial Tech (Ankit Patial).
+// All rights reserved.
+
+package request
+
+import (
+	"fmt"
+	"net/http"
+	"reflect"
+	"strconv"
+)
+
+type Number interface {
+	int | int8 | int16 | int32 | int64 | uint | uint8 | uint16 | uint32 | uint64 | float32 | float64
+}
+
+// NumberParam from request query string
+func NumberParam[T Number](r *http.Request, key string) (T, error) {
+	var noop T
+	if !r.URL.Query().Has(key) {
+		return noop, fmt.Errorf("query param: %q is missing", key)
+	}
+
+	p := r.URL.Query().Get(key)
+	t := reflect.TypeOf(noop)
+	k := t.Kind()
+	// float param
+	if k == reflect.Float32 || k == reflect.Float64 {
+		n, err := strconv.ParseFloat(p, 64)
+		if err != nil {
+			return noop, fmt.Errorf("query param: %q is not a valid float", key)
+		}
+		return T(n), nil
+	}
+
+	// int param
+	n, err := strconv.ParseInt(p, 10, 64)
+	if err != nil {
+		return noop, fmt.Errorf("query param: %q is not a valid integer", key)
+	}
+	return T(n), nil
+}