Redis

A Pacto contract for Redis — a stateful in-memory data store with persistent durability.

pactoVersion: "1.0"

service:
  name: redis
  version: 7.4.0
  owner: infra/caching
  image:
    ref: docker.io/library/redis:7.4
    private: false

interfaces:
  - name: resp
    type: grpc
    port: 6379
    visibility: internal
    contract: interfaces/redis-resp.proto

  - name: metrics
    type: http
    port: 9121
    visibility: internal

configurations:
  - name: default
    schema: configuration/schema.json

runtime:
  workload: service

  state:
    type: stateful
    persistence:
      scope: local
      durability: persistent
    dataCriticality: medium

  lifecycle:
    upgradeStrategy: ordered
    gracefulShutdownSeconds: 30

  health:
    interface: metrics
    path: /health

  metrics:
    interface: metrics
    path: /metrics

scaling:
  replicas: 1

metadata:
  tier: high
  eviction-policy: allkeys-lru

The resp interface uses type: grpc as the closest available protocol type for Redis’s RESP binary protocol. The Pacto schema currently supports http, grpc, and event — there is no dedicated tcp type. The .proto contract file is illustrative; in practice you may omit the interface or use a custom schema.

Key decisions

• state.type: stateful with durability: persistent — Redis with AOF/RDB persistence enabled needs durable storage
• dataCriticality: medium — data is important but can be rebuilt from source if needed
• upgradeStrategy: ordered — prevents data loss during upgrades

  Variant: Ephemeral cache

For a pure cache without persistence:

runtime:
  state:
    type: stateless
    persistence:
      scope: local
      durability: ephemeral
    dataCriticality: low