Function CRD

The Function CRD declares row-preserving compute over an Index. The operator creates worker resources; the gateway owns discovery, queueing, retries, leases, and writeback through the UDF API.

apiVersion: hevlayer.com/v1alpha1
kind: Function
metadata:
  name: tag-products
  namespace: layer
spec:
  targetNamespaces:
    - products
  inputs:
    - id
    - title
  output:
    attribute: tags
    kind: tags
    version: v1
  filter:
    - "Or"
    - - ["tags_v", "NotEq", "v1"]
      - ["tags_v", "Eq", null]
  worker:
    image: ghcr.io/hev/tag-products:latest
    dispatch: pull
    batchSize: 32
    timeoutSeconds: 30
  schedule:
    discoveryIntervalSeconds: 300
    leaseSeconds: 120
    maxInFlightBatches: 8
    maxConcurrentScans: 1
  retry:
    maxAttempts: 8
    initialBackoffSeconds: 5
    maxBackoffSeconds: 300
  triggers:
    - discovery
  scaling:
    pool: cpu
    mode: autoscale
    replicas:
      min: 0
      max: 6

Selection

Use targetNamespaces for explicit namespaces. Use indexSelector when labels on Index resources should choose the namespaces.

filter preserves arbitrary JSON, including array-form Turbopuffer filters. The operator stores the shape as-is; the gateway evaluates it during discovery.

Worker

Field	Purpose
image	Worker image.
dispatch	pull for SDK claim/poll workers, push for HTTP /run workers.
port	Push-dispatch service port.
batchSize	Rows per batch.
timeoutSeconds	Worker call timeout.
podSpec	Optional pod-level merge patch.

Pull dispatch creates a Deployment. Push dispatch also creates a Service and readiness probe.

Scaling

Function scaling is inline under spec.scaling. The operator emits a KEDA ScaledObject when mode: autoscale, using layer_udf_queue_depth for the trigger.

The selected pool must exist in InfraRules/default. Replica maxima above the pool’s maxReplicasPerWorkload are rejected in status.

Output

output.kind: embedding should set output.dim so consumers can validate vector shape. Outputs are patched onto the target row through the gateway.

Deleting a Function garbage-collects operator-managed Kubernetes resources. It does not delete already-written attributes.