miniflux/internal/proxy/proxy.go

// SPDX-FileCopyrightText: Copyright The Miniflux Authors. All rights reserved.
// SPDX-License-Identifier: Apache-2.0

package proxy // import "miniflux.app/v2/internal/proxy"

import (
	"crypto/hmac"
	"crypto/sha256"
	"encoding/base64"
	"net/url"
	"path"

	"miniflux.app/v2/internal/http/route"

	"github.com/gorilla/mux"

	"miniflux.app/v2/internal/config"
)

// ProxifyURL generates a relative URL for a proxified resource.
func ProxifyURL(router *mux.Router, link string) string {
	if link == "" {
		return ""
	}

	if proxyImageUrl := config.Opts.ProxyUrl(); proxyImageUrl != "" {
		proxyUrl, err := url.Parse(proxyImageUrl)
		if err != nil {
			return ""
		}
		proxyUrl.Path = path.Join(proxyUrl.Path, base64.URLEncoding.EncodeToString([]byte(link)))
		return proxyUrl.String()
	}

	mac := hmac.New(sha256.New, config.Opts.ProxyPrivateKey())
	mac.Write([]byte(link))
	digest := mac.Sum(nil)
	return route.Path(router, "proxy", "encodedDigest", base64.URLEncoding.EncodeToString(digest), "encodedURL", base64.URLEncoding.EncodeToString([]byte(link)))
}

// AbsoluteProxifyURL generates an absolute URL for a proxified resource.
func AbsoluteProxifyURL(router *mux.Router, host, link string) string {
	proxifiedUrl := ProxifyURL(router, link)

	if config.Opts.ProxyUrl() == "" {
		return proxifiedUrl
	}
	if config.Opts.HTTPS {
		return "https://" + host + proxifiedUrl
	}
	return "http://" + host + proxifiedUrl
}