HTTP traffic contract

Draincheck sends the configured HTTP request concurrently so real work is active when termination begins. The request can include a fixed body and an exact expected-status contract, which makes POST, PUT, and application-specific test endpoints usable in CI.

traffic:
  driver: http
  # container_port: 8081 # omitted inherits target.container_port
  request:
    method: POST
    path: /jobs?delay=2s
    headers:
      Content-Type: application/json
      Authorization: Bearer ci-only-token
    body_file: ./testdata/draincheck-job.json
    success_statuses: [202, 409]
  count: 5
  concurrency: 5
  shutdown_after: 500ms
  request_timeout: 10s

Request bodies

Configure no more than one body source:

• body contains a short inline string.
• body_file names a file relative to the directory containing draincheck.yaml. Absolute paths are accepted but make CI configurations less portable.

Draincheck reads and bounds the body before it creates the container. The maximum size is 1 MiB. Every worker receives an independent reader over the same immutable bytes, so concurrent requests and HTTP redirects can replay the payload safely. Draincheck does not infer Content-Type, parse JSON, expand environment variables, or template per-request identifiers; declare required headers and use deterministic test data.

The optional post-signal phase reuses the same method, path, headers, body, and status rule.

http is the default traffic.driver, so existing configurations may omit it. When traffic.driver is command or grpc, the HTTP request block is ignored. The command probe protocol or gRPC lifecycle adapter supplies the traffic evidence instead. traffic.container_port selects the workload listener for every traffic driver and defaults to target.container_port when omitted.

Expected status codes

When success_statuses is omitted or empty, HTTP 200 through 399 is successful. A non-empty list replaces that default with exact codes between 100 and 599:

success_statuses: [202]

With this configuration, HTTP 202 succeeds and HTTP 200 fails. The rule also defines post-signal acceptance: a matching response is accepted, while an unmatched status or transport failure is rejected.

Use expected statuses to express the endpoint's real test contract, not to hide server errors. A failed status is recorded as http_status with the numeric code in traffic evidence.

Security and artifacts

Request bodies should contain disposable test data, never production credentials or customer records. Inline bodies are replaced with [REDACTED] in debug configuration. File-backed contents are held only in memory for the run and are never embedded in JSON, JUnit, or debug artifacts; the configured file path remains visible. Draincheck also scrubs an exact configured body if that whole value appears in captured evidence, but it cannot reliably recognize fragments independently logged by the application.

Header values remain redacted under the existing debug-bundle contract. Protect container logs and debug bundles with normal CI artifact access controls.