eclipse-vertx/vert.x · error

502 Bad Gateway

Error message

502 Bad Gateway

What it means

Constant defining the 502 Bad Gateway response expectation: with expecting(SC_BAD_GATEWAY), a 502 response fails the request future. The server (acting as gateway/proxy) got an invalid upstream response; the 'message' is the reason attached to the expectation failure.

Source

Thrown at vertx-core/src/main/java/io/vertx/core/http/HttpResponseExpectation.java:300

  /**
   * Any 5XX server error
   */
  HttpResponseExpectation SC_SERVER_ERRORS = status(500, 600);

  /**
   * 500 Internal Server Error
   */
  HttpResponseExpectation SC_INTERNAL_SERVER_ERROR = status(500);

  /**
   * 501 Not Implemented
   */
  HttpResponseExpectation SC_NOT_IMPLEMENTED = status(501);

  /**
   * 502 Bad Gateway
   */
  HttpResponseExpectation SC_BAD_GATEWAY = status(502);

  /**
   * 503 Service Unavailable
   */
  HttpResponseExpectation SC_SERVICE_UNAVAILABLE = status(503);

  /**
   * 504 Gateway Timeout
   */
  HttpResponseExpectation SC_GATEWAY_TIMEOUT = status(504);

  /**
   * 505 HTTP Version Not Supported
   */
  HttpResponseExpectation SC_HTTP_VERSION_NOT_SUPPORTED = status(505);

  /**
   * 506 Variant Also Negotiates (RFC2295)

View on GitHub (pinned to fb308bd8c3)

Solutions

1. Retry the request, as 502 is often a transient upstream failure
2. Report the upstream problem if it persists

When it happens

Trigger: Thrown at vertx-core/src/main/java/io/vertx/core/http/HttpResponseExpectation.java:300 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• HTTP status errors: handling 4xx and 5xx responses — how to handle 4xx and 5xx responses properly.

AI-assisted analysis of eclipse-vertx/vert.x@fb308bd8c3 (2026-09-06). Data as JSON: /api/errors/78a0c888ebf79498. Report an issue: GitHub.