Failed to read error stream from Firebase HTTP connection

Error message

Failed to read error stream from Firebase HTTP connection

What it means

FirebaseHttpClient.readErrorStream reads the HTTP error body from a failed Firebase connection (bounded by MAX_ERROR_BODY_BYTES); if reading the stream throws an IOException, this warning is logged and an empty string is returned so the caller can still build an error from whatever is available. The original HTTP error will then surface without its body detail.

Source

Thrown at seatunnel-connectors-v2/connector-firebase/src/main/java/org/apache/seatunnel/connectors/seatunnel/firebase/client/FirebaseHttpClient.java:261

            StringBuilder builder = new StringBuilder();
            char[] buffer = new char[1024];
            int bytesRead;
            int totalRead = 0;
            while ((bytesRead =
                            reader.read(
                                    buffer,
                                    0,
                                    Math.min(buffer.length, MAX_ERROR_BODY_BYTES - totalRead)))
                    != -1) {
                builder.append(buffer, 0, bytesRead);
                totalRead += bytesRead;
                if (totalRead >= MAX_ERROR_BODY_BYTES) {
                    break;
                }
            }
            return builder.toString().trim();
        } catch (IOException e) {
            log.warn("Failed to read error stream from Firebase HTTP connection", e);
            return "";
        }
    }

    /** Retrieves or refreshes OAuth 2.0 access token safely. */
    private synchronized String getAccessToken() throws IOException {
        tokenLock.lock();
        try {
            AccessToken token = credentials.getAccessToken();
            if (token == null
                    || token.getExpirationTime() == null
                    || token.getExpirationTime().getTime() <= System.currentTimeMillis() + 60000) {
                credentials.refresh();
                token = credentials.getAccessToken();
            }
            return token.getTokenValue();
        } finally {
            tokenLock.unlock();

View on GitHub (pinned to cf67b549a7)

Solutions

Check the primary HTTP error/status handling — the empty error body is secondary
Retry the request; transient resets usually disappear
Verify proxy/firewall/TLS settings between the client and Firebase endpoints
Increase read timeout on the HTTP connection if large error bodies are truncated

Defensive patterns

Strategy: fallback

Validate before calling

// Guard before reading the error stream
URLConnection conn = ...;
if (conn == null) return "";
InputStream err = ((HttpURLConnection) conn).getErrorStream();
if (err == null) return ""; // no error body available

Try / catch

try { body = readErrorStream(conn); } catch (IOException e) { body = ""; } // then build the error message with HTTP status even when body is empty

Prevention

Always null-check getErrorStream() before reading
Bound error-body reads (as done with MAX_ERROR_BODY_BYTES) and set sane read timeouts
Retry transient resets; surface HTTP status even when the body is unreadable

When it happens

Trigger: rawErrorBody -> readErrorStream on an HttpURLConnection's error stream when the server closed the connection mid-body, the stream is already consumed, or a network interruption occurs while reading the error payload.

Common situations: Firebase/Google endpoints returning truncated error responses; TLS or proxy interception killing the stream; timeouts on error responses; retry storms producing connection resets.

Related errors

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/ea1a657a4394040e. Report an issue: GitHub.