Adjust HTTPError to read response body before it is closed

Author: Nathan

coder-sdk/activity.go

@@ -21,7 +21,7 @@ func (c *DefaultClient) PushActivity(ctx context.Context, source, workspaceID st
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return bodyError(resp)
+		return NewHTTPError(resp)
 	}
 	return nil
 }

coder-sdk/error.go

@@ -1,8 +1,10 @@
 package coder
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
+	"io"
 	"net/http"
 
 	"golang.org/x/xerrors"
@@ -29,11 +31,31 @@ type APIErrorMsg struct {
 	Details json.RawMessage `json:"details"`
 }
 
+// NewHTTPError reads the response body and stores metadata
+// about the response in order to be unpacked into
+// an *APIError.
+func NewHTTPError(resp *http.Response) *HTTPError {
+	var buf bytes.Buffer
+	_, err := io.CopyN(&buf, resp.Body, 1<<6)
+	if err != nil {
+		return &HTTPError{
+			cachedErr: err,
+		}
+	}
+	return &HTTPError{
+		url:        resp.Request.URL.String(),
+		statusCode: resp.StatusCode,
+		body:       buf.Bytes(),
+	}
+}
+
 // HTTPError represents an error from the Coder API.
 type HTTPError struct {
-	*http.Response
-	cached    *APIError
-	cachedErr error
+	url        string
+	statusCode int
+	body       []byte
+	cached     *APIError
+	cachedErr  error
 }
 
 // Payload decode the response body into the standard error structure. The `details`
@@ -46,7 +68,7 @@ func (e *HTTPError) Payload() (*APIError, error) {
 
 	// Try to decode the payload as an error, if it fails or if there is no error message,
 	// return the response URL with the status.
-	if err := json.NewDecoder(e.Response.Body).Decode(&msg); err != nil {
+	if err := json.Unmarshal(e.body, &msg); err != nil {
 		e.cachedErr = err
 		return nil, err
 	}
@@ -55,16 +77,16 @@ func (e *HTTPError) Payload() (*APIError, error) {
 	return &msg, nil
 }
 
+func (e *HTTPError) StatusCode() int {
+	return e.statusCode
+}
+
 func (e *HTTPError) Error() string {
 	apiErr, err := e.Payload()
 	if err != nil || apiErr.Err.Msg == "" {
-		return fmt.Sprintf("%s: %d %s", e.Request.URL, e.StatusCode, e.Status)
+		return fmt.Sprintf("%s: %d %s", e.url, e.statusCode, http.StatusText(e.statusCode))
 	}
 
 	// If the payload was a in the expected error format with a message, include it.
 	return apiErr.Err.Msg
 }
-
-func bodyError(resp *http.Response) error {
-	return &HTTPError{Response: resp}
-}

coder-sdk/request.go

@@ -114,7 +114,7 @@ func (c *DefaultClient) requestBody(ctx context.Context, method, path string, in
 	// Responses in the 100 are handled by the http lib, in the 200 range, we have a success.
 	// Consider anything at or above 300 to be an error.
 	if resp.StatusCode > 299 {
-		return fmt.Errorf("unexpected status code %d: %w", resp.StatusCode, bodyError(resp))
+		return fmt.Errorf("unexpected status code %d: %w", resp.StatusCode, NewHTTPError(resp))
 	}
 
 	// If we expect a payload, process it as json.

coder-sdk/ws.go

@@ -26,7 +26,7 @@ func (c *DefaultClient) dialWebsocket(ctx context.Context, path string, options
 	conn, resp, err := websocket.Dial(ctx, url.String(), &websocket.DialOptions{HTTPHeader: headers})
 	if err != nil {
 		if resp != nil {
-			return nil, bodyError(resp)
+			return nil, NewHTTPError(resp)
 		}
 		return nil, err
 	}

internal/cmd/auth.go

@@ -66,7 +66,7 @@ func newClient(ctx context.Context, checkVersion bool) (coder.Client, error) {
 	if err != nil {
 		var he *coder.HTTPError
 		if xerrors.As(err, &he) {
-			if he.StatusCode == http.StatusUnauthorized {
+			if he.StatusCode() == http.StatusUnauthorized {
 				return nil, xerrors.Errorf("not authenticated: try running \"coder login`\"")
 			}
 		}

internal/cmd/errors.go

@@ -61,7 +61,7 @@ func handleAPIError(origError error) error {
 			return origError
 		}
 
-		return clog.Error(fmt.Sprintf("Precondition Error : Status Code=%d", httpError.StatusCode),
+		return clog.Error(fmt.Sprintf("Precondition Error : Status Code=%d", httpError.StatusCode()),
 			p.Message,
 			clog.BlankLine,
 			clog.Tipf(p.Solution))

wsnet/dial.go

@@ -24,9 +24,7 @@ func DialWebsocket(ctx context.Context, broker string, iceServers []webrtc.ICESe
 			defer func() {
 				_ = resp.Body.Close()
 			}()
-			return nil, &coder.HTTPError{
-				Response: resp,
-			}
+			return nil, coder.NewHTTPError(resp)
 		}
 		return nil, fmt.Errorf("dial websocket: %w", err)
 	}

wsnet/listen.go

@@ -81,9 +81,7 @@ func (l *listener) dial(ctx context.Context) (<-chan error, error) {
 	conn, resp, err := websocket.Dial(ctx, l.broker, nil)
 	if err != nil {
 		if resp != nil {
-			return nil, &coder.HTTPError{
-				Response: resp,
-			}
+			return nil, coder.NewHTTPError(resp)
 		}
 		return nil, err
 	}