FEAT: Added Redis Caching

docker-compose.yml

@@ -126,6 +126,23 @@ services:
         - action: rebuild
           path: ./cms
 
+  # Stands in for the ElastiCache node infrastructure/main.go provisions on the
+  # AWS stacks. Not provisioned through LocalStack like the buckets and the
+  # database are: ElastiCache hands out an endpoint on a port it chooses, and
+  # the literal REDIS_ADDR below has to be known before anything is created.
+  # Nothing here is worth persisting — every entry is derivable from Postgres,
+  # which is the whole point of a cache — so there is no volume.
+  redis:
+    container_name: "${REDIS_DOCKER_NAME:-redis}"
+    image: redis:7-alpine
+    ports:
+      - "127.0.0.1:6379:6379"
+    healthcheck:
+      test: ["CMD", "redis-cli", "ping"]
+      interval: 5s
+      timeout: 3s
+      retries: 10
+
   discovery:
     container_name: "${DISCOVERY_DOCKER_NAME:-discovery}"
     build:
@@ -143,6 +160,10 @@ services:
       - AWS_SECRET_ACCESS_KEY=${AWS_SECRET_ACCESS_KEY:-test}
       - AWS_ENDPOINT_URL=${AWS_ENDPOINT_URL:-http://localhost.localstack.cloud:4566}
       - CATALOGUE_EVENTS_QUEUE_URL=${CATALOGUE_EVENTS_QUEUE_URL:-http://localhost.localstack.cloud:4566/000000000000/discovery-catalogue-events}
+      # The catalogue search's cache — the redis service below, standing in for
+      # ElastiCache. main.go panics without an address but only warns if the
+      # node does not answer: a cold cache means slower searches, not none.
+      - REDIS_ADDR=${REDIS_ADDR:-redis:6379}
       # Postgres: its own role and database, provisioned alongside the cms ones
       # by newServiceDatabase, so the two services share no credentials.
       - DB_HOST=${DISCOVERY_DB_HOST:-localhost.localstack.cloud}
@@ -154,6 +175,8 @@ services:
     depends_on:
       infra:
         condition: service_completed_successfully
+      redis:
+        condition: service_healthy
     develop:
       watch:
         # Same as cms: a compiled binary, so every change means a new image.