code.gitea.io/gitea@v1.21.7/routers/common/redirect.go (about)

     1  // Copyright 2023 The Gitea Authors. All rights reserved.
     2  // SPDX-License-Identifier: MIT
     3  
     4  package common
     5  
     6  import (
     7  	"net/http"
     8  
     9  	"code.gitea.io/gitea/modules/httplib"
    10  )
    11  
    12  // FetchRedirectDelegate helps the "fetch" requests to redirect to the correct location
    13  func FetchRedirectDelegate(resp http.ResponseWriter, req *http.Request) {
    14  	// When use "fetch" to post requests and the response is a redirect, browser's "location.href = uri" has limitations.
    15  	// 1. change "location" from old "/foo" to new "/foo#hash", the browser will not reload the page.
    16  	// 2. when use "window.reload()", the hash is not respected, the newly loaded page won't scroll to the hash target.
    17  	// The typical page is "issue comment" page. The backend responds "/owner/repo/issues/1#comment-2",
    18  	// then frontend needs this delegate to redirect to the new location with hash correctly.
    19  	redirect := req.PostFormValue("redirect")
    20  	if httplib.IsRiskyRedirectURL(redirect) {
    21  		resp.WriteHeader(http.StatusBadRequest)
    22  		return
    23  	}
    24  	resp.Header().Add("Location", redirect)
    25  	resp.WriteHeader(http.StatusSeeOther)
    26  }