Use vanilla HTTP handlers (refactoring)

http/request/request.go

@@ -0,0 +1,90 @@
+// Copyright 2018 Frédéric Guillot. All rights reserved.
+// Use of this source code is governed by the Apache 2.0
+// license that can be found in the LICENSE file.
+
+package request
+
+import (
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/gorilla/mux"
+)
+
+// Cookie returns the cookie value.
+func Cookie(r *http.Request, name string) string {
+	cookie, err := r.Cookie(name)
+	if err == http.ErrNoCookie {
+		return ""
+	}
+
+	return cookie.Value
+}
+
+// FormIntValue returns a form value as integer.
+func FormIntValue(r *http.Request, param string) int64 {
+	value := r.FormValue(param)
+	integer, _ := strconv.Atoi(value)
+	return int64(integer)
+}
+
+// IntParam returns an URL route parameter as integer.
+func IntParam(r *http.Request, param string) (int64, error) {
+	vars := mux.Vars(r)
+	value, err := strconv.Atoi(vars[param])
+	if err != nil {
+		return 0, fmt.Errorf("request: %s parameter is not an integer", param)
+	}
+
+	if value < 0 {
+		return 0, nil
+	}
+
+	return int64(value), nil
+}
+
+// Param returns an URL route parameter as string.
+func Param(r *http.Request, param, defaultValue string) string {
+	vars := mux.Vars(r)
+	value := vars[param]
+	if value == "" {
+		value = defaultValue
+	}
+	return value
+}
+
+// QueryParam returns a querystring parameter as string.
+func QueryParam(r *http.Request, param, defaultValue string) string {
+	value := r.URL.Query().Get(param)
+	if value == "" {
+		value = defaultValue
+	}
+	return value
+}
+
+// QueryIntParam returns a querystring parameter as integer.
+func QueryIntParam(r *http.Request, param string, defaultValue int) int {
+	value := r.URL.Query().Get(param)
+	if value == "" {
+		return defaultValue
+	}
+
+	val, err := strconv.Atoi(value)
+	if err != nil {
+		return defaultValue
+	}
+
+	if val < 0 {
+		return defaultValue
+	}
+
+	return val
+}
+
+// HasQueryParam checks if the query string contains the given parameter.
+func HasQueryParam(r *http.Request, param string) bool {
+	values := r.URL.Query()
+	_, ok := values[param]
+	return ok
+}