// GoToSocial // Copyright (C) GoToSocial Authors admin@gotosocial.org // SPDX-License-Identifier: AGPL-3.0-or-later // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Affero General Public License for more details. // // You should have received a copy of the GNU Affero General Public License // along with this program. If not, see . package middleware import ( "strings" "github.com/gin-gonic/gin" ) type CacheControlConfig struct { // Slice of Cache-Control directives, which will be // joined comma-separated and served as the value of // the Cache-Control header. // // If no directives are set, the Cache-Control header // will not be sent in the response at all. // // For possible Cache-Control directive values, see: // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control Directives []string // Slice of Vary header values, which will be joined // comma-separated and served as the value of the Vary // header in the response. // // If no Vary header values are supplied, then the // Vary header will be omitted in the response. // // https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Vary Vary []string } // CacheControl returns a new gin middleware which allows // routes to control cache settings on response headers. func CacheControl(config CacheControlConfig) gin.HandlerFunc { if len(config.Directives) == 0 { // No Cache-Control directives provided, // return empty/stub function. return func(c *gin.Context) {} } // Cache control is usually done on hot paths so // parse vars outside of the returned function. var ( ccHeader = strings.Join(config.Directives, ", ") varyHeader = strings.Join(config.Vary, ", ") ) if varyHeader == "" { return func(c *gin.Context) { c.Header("Cache-Control", ccHeader) } } return func(c *gin.Context) { c.Header("Cache-Control", ccHeader) c.Header("Vary", varyHeader) } }