Pretty Charts: operators

What a supplier needs to serve pretty-charts.

Service ID: pretty-charts
Required version: pretty-charts >= 1.0
Image: ghcr.io/thefeloniousmonk/pretty-charts:1.0.1
Minimum RAM: 1 GB
Minimum disk: 1 GB
RPC types: REST (expected)

Backend

The pretty-charts container (Node 22, Vega 6, Vega-Lite 6; built from github.com/TheFeloniousMonk/portal-services, pretty-charts/backend) behind the HA RelayMiner with the rest backend pointed at it. No auth toward the backend; callers cannot send headers. CPU-bound; about 150 MB RAM per render worker (PC_WORKERS, default 2). Caps are PC_* environment variables.

REST

Backend: pretty-charts container on :8080; mount at /

POST /v1/chart, GET /v1/version, GET /healthz, GET /v1/capabilities, and GET /v1/openapi.json are expected. Every response is a JSON object; the SVG or HTML rides in the 'html' string field, always last.

Notes

Every request is a POST JSON body to /v1/chart; typical renders finish in well under a second. No rate limits to disable. SAGE operators: type generic (its name for passthrough), rpc_types ["rest"], relay_timeout at least 15s; see sage-service.yaml in the service repository.

Health checks

Type	Request	Expect	Why
REST	`GET /v1/version`	`$.service` matches `^pretty-charts$`	Identity probe: pins the backend to this service so a wrong backend cannot be staked under this id.
REST	`GET /healthz`	`$.status` matches `^ok$`	Readiness probe: 200 only once a render worker is up.
REST	`POST /v1/chart` `{"data":{"values":[{"a":"A","b":1}]},"chart":{"type":"bar","x":"a","y":"b","tooltip":false}}`	`$.marks` matches `^1$`	Functional probe: renders one bar and reports one data mark. Cheap and deterministic.

Running it

Build the backend from backend/, or pull the published image:

docker pull ghcr.io/thefeloniousmonk/pretty-charts:1.0.1

Images are tagged with the version the backend reports at GET /v1/version. Keep up with the required version above; an older backend can reject requests that newer callers send.

The service's deploy/ folder has:

The service's docs cover its settings and anything a supplier must provide.