package dependencyproxy import ( "context" "fmt" "io" "net/http" "gitlab.com/gitlab-org/labkit/log" "gitlab.com/gitlab-org/gitlab/workhorse/internal/helper" "gitlab.com/gitlab-org/gitlab/workhorse/internal/helper/httptransport" "gitlab.com/gitlab-org/gitlab/workhorse/internal/senddata" ) var httpClient = &http.Client{ Transport: httptransport.New(), } type Injector struct { senddata.Prefix uploadHandler http.Handler } type entryParams struct { Url string Header http.Header } type nullResponseWriter struct { header http.Header status int } func (nullResponseWriter) Write(p []byte) (int, error) { return len(p), nil } func (w *nullResponseWriter) Header() http.Header { return w.header } func (w *nullResponseWriter) WriteHeader(status int) { if w.status == 0 { w.status = status } } func NewInjector() *Injector { return &Injector{Prefix: "send-dependency:"} } func (p *Injector) SetUploadHandler(uploadHandler http.Handler) { p.uploadHandler = uploadHandler } func (p *Injector) Inject(w http.ResponseWriter, r *http.Request, sendData string) { dependencyResponse, err := p.fetchUrl(r.Context(), sendData) if err != nil { helper.Fail500(w, r, err) return } defer dependencyResponse.Body.Close() if dependencyResponse.StatusCode >= 400 { w.WriteHeader(dependencyResponse.StatusCode) io.Copy(w, dependencyResponse.Body) return } w.Header().Set("Content-Length", dependencyResponse.Header.Get("Content-Length")) teeReader := io.TeeReader(dependencyResponse.Body, w) saveFileRequest, err := http.NewRequestWithContext(r.Context(), "POST", r.URL.String()+"/upload", teeReader) if err != nil { helper.Fail500(w, r, fmt.Errorf("dependency proxy: failed to create request: %w", err)) } saveFileRequest.Header = helper.HeaderClone(r.Header) // forward headers from dependencyResponse to rails and client for key, values := range dependencyResponse.Header { saveFileRequest.Header.Del(key) w.Header().Del(key) for _, value := range values { saveFileRequest.Header.Add(key, value) w.Header().Add(key, value) } } // workhorse hijack overwrites the Content-Type header, but we need this header value saveFileRequest.Header.Set("Workhorse-Proxy-Content-Type", dependencyResponse.Header.Get("Content-Type")) saveFileRequest.ContentLength = dependencyResponse.ContentLength nrw := &nullResponseWriter{header: make(http.Header)} p.uploadHandler.ServeHTTP(nrw, saveFileRequest) if nrw.status != http.StatusOK { fields := log.Fields{"code": nrw.status} helper.Fail500WithFields(nrw, r, fmt.Errorf("dependency proxy: failed to upload file"), fields) } } func (p *Injector) fetchUrl(ctx context.Context, sendData string) (*http.Response, error) { var params entryParams if err := p.Unpack(¶ms, sendData); err != nil { return nil, fmt.Errorf("dependency proxy: unpack sendData: %v", err) } r, err := http.NewRequestWithContext(ctx, "GET", params.Url, nil) if err != nil { return nil, fmt.Errorf("dependency proxy: failed to fetch dependency: %v", err) } r.Header = params.Header return httpClient.Do(r) }