diff options
Diffstat (limited to 'vendor/github.com/slack-go/slack/misc.go')
-rw-r--r-- | vendor/github.com/slack-go/slack/misc.go | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/vendor/github.com/slack-go/slack/misc.go b/vendor/github.com/slack-go/slack/misc.go new file mode 100644 index 00000000..0dcee950 --- /dev/null +++ b/vendor/github.com/slack-go/slack/misc.go @@ -0,0 +1,360 @@ +package slack + +import ( + "bytes" + "context" + "encoding/json" + "errors" + "fmt" + "io" + "io/ioutil" + "mime" + "mime/multipart" + "net/http" + "net/http/httputil" + "net/url" + "os" + "path/filepath" + "strconv" + "strings" + "time" +) + +// SlackResponse handles parsing out errors from the web api. +type SlackResponse struct { + Ok bool `json:"ok"` + Error string `json:"error"` +} + +func (t SlackResponse) Err() error { + if t.Ok { + return nil + } + + // handle pure text based responses like chat.post + // which while they have a slack response in their data structure + // it doesn't actually get set during parsing. + if strings.TrimSpace(t.Error) == "" { + return nil + } + + return errors.New(t.Error) +} + +// StatusCodeError represents an http response error. +// type httpStatusCode interface { HTTPStatusCode() int } to handle it. +type statusCodeError struct { + Code int + Status string +} + +func (t statusCodeError) Error() string { + return fmt.Sprintf("slack server error: %s", t.Status) +} + +func (t statusCodeError) HTTPStatusCode() int { + return t.Code +} + +func (t statusCodeError) Retryable() bool { + if t.Code >= 500 || t.Code == http.StatusTooManyRequests { + return true + } + return false +} + +// RateLimitedError represents the rate limit respond from slack +type RateLimitedError struct { + RetryAfter time.Duration +} + +func (e *RateLimitedError) Error() string { + return fmt.Sprintf("slack rate limit exceeded, retry after %s", e.RetryAfter) +} + +func (e *RateLimitedError) Retryable() bool { + return true +} + +func fileUploadReq(ctx context.Context, path string, values url.Values, r io.Reader) (*http.Request, error) { + req, err := http.NewRequest("POST", path, r) + if err != nil { + return nil, err + } + + req = req.WithContext(ctx) + req.URL.RawQuery = (values).Encode() + return req, nil +} + +func downloadFile(client httpClient, token string, downloadURL string, writer io.Writer, d debug) error { + if downloadURL == "" { + return fmt.Errorf("received empty download URL") + } + + req, err := http.NewRequest("GET", downloadURL, &bytes.Buffer{}) + if err != nil { + return err + } + + var bearer = "Bearer " + token + req.Header.Add("Authorization", bearer) + req.WithContext(context.Background()) + + resp, err := client.Do(req) + if err != nil { + return err + } + + defer resp.Body.Close() + + err = checkStatusCode(resp, d) + if err != nil { + return err + } + + _, err = io.Copy(writer, resp.Body) + + return err +} + +func formReq(endpoint string, values url.Values) (req *http.Request, err error) { + if req, err = http.NewRequest("POST", endpoint, strings.NewReader(values.Encode())); err != nil { + return nil, err + } + + req.Header.Set("Content-Type", "application/x-www-form-urlencoded") + return req, nil +} + +func jsonReq(endpoint string, body interface{}) (req *http.Request, err error) { + buffer := bytes.NewBuffer([]byte{}) + if err = json.NewEncoder(buffer).Encode(body); err != nil { + return nil, err + } + + if req, err = http.NewRequest("POST", endpoint, buffer); err != nil { + return nil, err + } + + req.Header.Set("Content-Type", "application/json; charset=utf-8") + return req, nil +} + +func parseResponseBody(body io.ReadCloser, intf interface{}, d debug) error { + response, err := ioutil.ReadAll(body) + if err != nil { + return err + } + + if d.Debug() { + d.Debugln("parseResponseBody", string(response)) + } + + return json.Unmarshal(response, intf) +} + +func postLocalWithMultipartResponse(ctx context.Context, client httpClient, method, fpath, fieldname string, values url.Values, intf interface{}, d debug) error { + fullpath, err := filepath.Abs(fpath) + if err != nil { + return err + } + file, err := os.Open(fullpath) + if err != nil { + return err + } + defer file.Close() + + return postWithMultipartResponse(ctx, client, method, filepath.Base(fpath), fieldname, values, file, intf, d) +} + +func postWithMultipartResponse(ctx context.Context, client httpClient, path, name, fieldname string, values url.Values, r io.Reader, intf interface{}, d debug) error { + pipeReader, pipeWriter := io.Pipe() + wr := multipart.NewWriter(pipeWriter) + errc := make(chan error) + go func() { + defer pipeWriter.Close() + ioWriter, err := wr.CreateFormFile(fieldname, name) + if err != nil { + errc <- err + return + } + _, err = io.Copy(ioWriter, r) + if err != nil { + errc <- err + return + } + if err = wr.Close(); err != nil { + errc <- err + return + } + }() + req, err := fileUploadReq(ctx, path, values, pipeReader) + if err != nil { + return err + } + req.Header.Add("Content-Type", wr.FormDataContentType()) + req = req.WithContext(ctx) + resp, err := client.Do(req) + + if err != nil { + return err + } + defer resp.Body.Close() + + err = checkStatusCode(resp, d) + if err != nil { + return err + } + + select { + case err = <-errc: + return err + default: + return newJSONParser(intf)(resp) + } +} + +func doPost(ctx context.Context, client httpClient, req *http.Request, parser responseParser, d debug) error { + req = req.WithContext(ctx) + resp, err := client.Do(req) + if err != nil { + return err + } + defer resp.Body.Close() + + err = checkStatusCode(resp, d) + if err != nil { + return err + } + + return parser(resp) +} + +// post JSON. +func postJSON(ctx context.Context, client httpClient, endpoint, token string, json []byte, intf interface{}, d debug) error { + reqBody := bytes.NewBuffer(json) + req, err := http.NewRequest("POST", endpoint, reqBody) + if err != nil { + return err + } + req.Header.Set("Content-Type", "application/json") + req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token)) + + return doPost(ctx, client, req, newJSONParser(intf), d) +} + +// post a url encoded form. +func postForm(ctx context.Context, client httpClient, endpoint string, values url.Values, intf interface{}, d debug) error { + reqBody := strings.NewReader(values.Encode()) + req, err := http.NewRequest("POST", endpoint, reqBody) + if err != nil { + return err + } + req.Header.Set("Content-Type", "application/x-www-form-urlencoded") + return doPost(ctx, client, req, newJSONParser(intf), d) +} + +func getResource(ctx context.Context, client httpClient, endpoint string, values url.Values, intf interface{}, d debug) error { + req, err := http.NewRequest("GET", endpoint, nil) + if err != nil { + return err + } + req.Header.Set("Content-Type", "application/x-www-form-urlencoded") + req.URL.RawQuery = values.Encode() + + return doPost(ctx, client, req, newJSONParser(intf), d) +} + +func parseAdminResponse(ctx context.Context, client httpClient, method string, teamName string, values url.Values, intf interface{}, d debug) error { + endpoint := fmt.Sprintf(WEBAPIURLFormat, teamName, method, time.Now().Unix()) + return postForm(ctx, client, endpoint, values, intf, d) +} + +func logResponse(resp *http.Response, d debug) error { + if d.Debug() { + text, err := httputil.DumpResponse(resp, true) + if err != nil { + return err + } + d.Debugln(string(text)) + } + + return nil +} + +func okJSONHandler(rw http.ResponseWriter, r *http.Request) { + rw.Header().Set("Content-Type", "application/json") + response, _ := json.Marshal(SlackResponse{ + Ok: true, + }) + rw.Write(response) +} + +// timerReset safely reset a timer, see time.Timer.Reset for details. +func timerReset(t *time.Timer, d time.Duration) { + if !t.Stop() { + <-t.C + } + t.Reset(d) +} + +func checkStatusCode(resp *http.Response, d debug) error { + if resp.StatusCode == http.StatusTooManyRequests { + retry, err := strconv.ParseInt(resp.Header.Get("Retry-After"), 10, 64) + if err != nil { + return err + } + return &RateLimitedError{time.Duration(retry) * time.Second} + } + + // Slack seems to send an HTML body along with 5xx error codes. Don't parse it. + if resp.StatusCode != http.StatusOK { + logResponse(resp, d) + return statusCodeError{Code: resp.StatusCode, Status: resp.Status} + } + + return nil +} + +type responseParser func(*http.Response) error + +func newJSONParser(dst interface{}) responseParser { + return func(resp *http.Response) error { + return json.NewDecoder(resp.Body).Decode(dst) + } +} + +func newTextParser(dst interface{}) responseParser { + return func(resp *http.Response) error { + b, err := ioutil.ReadAll(resp.Body) + if err != nil { + return err + } + + if !bytes.Equal(b, []byte("ok")) { + return errors.New(string(b)) + } + + return nil + } +} + +func newContentTypeParser(dst interface{}) responseParser { + return func(req *http.Response) (err error) { + var ( + ctype string + ) + + if ctype, _, err = mime.ParseMediaType(req.Header.Get("Content-Type")); err != nil { + return err + } + + switch ctype { + case "application/json": + return newJSONParser(dst)(req) + default: + return newTextParser(dst)(req) + } + } +} |