Static Responses

Static upstreams return a pre-built response directly from the gateway without proxying to a backend. Useful for health endpoints, mocks, redirects, and fallback responses.

Working example: see examples/static-responses/

Configuration

Set kind: "static" on x-plenum-upstream:

x-plenum-upstream:
  kind: "static"
  status: 200
  headers:
    Content-Type: application/json
  body: '{"status": "healthy"}'

Field	Required	Description
kind	Yes	Must be "static"
status	Yes	HTTP status code
headers	No	Response headers
body	No	Response body (string)

Examples

Health endpoint

overlay-static.yaml

actions:
  - target: "$.paths['/health'].get"
    update:
      x-plenum-upstream:
        kind: "static"
        status: 200
        headers:
          Content-Type: application/json
        body: '{"status": "healthy"}'

$ curl http://localhost:6188/health
{"status": "healthy"}

Redirect

x-plenum-upstream:
  kind: "static"
  status: 301
  headers:
    Location: "https://example.com/new-path"

Empty response

x-plenum-upstream:
  kind: "static"
  status: 204

Mixing with proxied routes

Static and proxied routes can coexist in the same spec. Apply the static upstream to specific paths and proxy the rest:

actions:
  # Static health endpoint
  - target: "$.paths['/health']"
    update:
      x-plenum-upstream:
        kind: "static"
        status: 200
        headers:
          Content-Type: application/json
        body: '{"status": "healthy"}'

  # Proxy everything else
  - target: "$.paths['/products']"
    update:
      x-plenum-upstream:
        $ref: "#/components/x-upstreams/default"