func ContextClient(ctx context.Context) (*http.Client, error) { if ctx != nil { if hc, ok := ctx.Value(HTTPClient).(*http.Client); ok { return hc, nil } } for _, fn := range contextClientFuncs { c, err := fn(ctx) if err != nil { return nil, err } if c != nil { return c, nil } } return http.DefaultClient, nil }
// Do sends an HTTP request with the provided http.Client and returns an HTTP response. // If the client is nil, http.DefaultClient is used. // If the context is canceled or times out, ctx.Err() will be returned. func Do(ctx context.Context, client *http.Client, req *http.Request) (*http.Response, error) { if client == nil { client = http.DefaultClient } // Request cancelation changed in Go 1.5, see cancelreq.go and cancelreq_go14.go. cancel := canceler(client, req) type responseAndError struct { resp *http.Response err error } result := make(chan responseAndError, 1) go func() { resp, err := client.Do(req) testHookDoReturned() result <- responseAndError{resp, err} }() var resp *http.Response select { case <-ctx.Done(): testHookContextDoneBeforeHeaders() cancel() // Clean up after the goroutine calling client.Do: go func() { if r := <-result; r.resp != nil { testHookDidBodyClose() r.resp.Body.Close() } }() return nil, ctx.Err() case r := <-result: var err error resp, err = r.resp, r.err if err != nil { return resp, err } } c := make(chan struct{}) go func() { select { case <-ctx.Done(): cancel() case <-c: // The response's Body is closed. } }() resp.Body = ¬ifyingReader{resp.Body, c} return resp, nil }