Improve request package and add more unit tests

http/request/params.go

@@ -0,0 +1,84 @@
+// 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 "miniflux.app/http/request"
+
+import (
+	"net/http"
+	"strconv"
+
+	"github.com/gorilla/mux"
+)
+
+// FormInt64Value returns a form value as integer.
+func FormInt64Value(r *http.Request, param string) int64 {
+	value := r.FormValue(param)
+	integer, err := strconv.ParseInt(value, 10, 64)
+	if err != nil {
+		return 0
+	}
+
+	return integer
+}
+
+// RouteInt64Param returns an URL route parameter as int64.
+func RouteInt64Param(r *http.Request, param string) int64 {
+	vars := mux.Vars(r)
+	value, err := strconv.ParseInt(vars[param], 10, 64)
+	if err != nil {
+		return 0
+	}
+
+	if value < 0 {
+		return 0
+	}
+
+	return value
+}
+
+// RouteStringParam returns a URL route parameter as string.
+func RouteStringParam(r *http.Request, param string) string {
+	vars := mux.Vars(r)
+	return vars[param]
+}
+
+// QueryStringParam returns a query string parameter as string.
+func QueryStringParam(r *http.Request, param, defaultValue string) string {
+	value := r.URL.Query().Get(param)
+	if value == "" {
+		value = defaultValue
+	}
+	return value
+}
+
+// QueryIntParam returns a query string parameter as integer.
+func QueryIntParam(r *http.Request, param string, defaultValue int) int {
+	return int(QueryInt64Param(r, param, int64(defaultValue)))
+}
+
+// QueryInt64Param returns a query string parameter as int64.
+func QueryInt64Param(r *http.Request, param string, defaultValue int64) int64 {
+	value := r.URL.Query().Get(param)
+	if value == "" {
+		return defaultValue
+	}
+
+	val, err := strconv.ParseInt(value, 10, 64)
+	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
+}