How to automatically restart KrakenD when rabbitMQ connection is not available?

[shi-rudo]

I have the problem when I start krakend before my rabbitMQ server that I have to restart the server krakend server to establish a connection.

The Krachend server is ready before the startup process of the rabbit is completed. Or also if the Krakend server was started before the RabbitMq server. Unfortunately, I could not find anything in the documentation how to solve the problem. Is there any war to automatically trigger a krakend reboot or exit when the connection fails?

Running on docker compose:

Steps:
01: Starting RabbitMQ
02: Starting krakend
03: Calling krakend endpoint
--> ❌ KRAKEND ERROR: [ENDPOINT: /api/user/register-user/:key] Post "amqp://guest:***@rabbit:5672/": unsupported protocol scheme "amqp".
04: Restarting krakend
05: Calling krakend endpoint
--> ✅ Success

THANKS A LOT!

{
  "version":3,
  "timeout": "2000ms",
  "port":8080,
  "async_agent": [
    {
      "name": "cool-agent",
      "connection": {
        "max_retries": 10,
        "backoff_strategy":"exponential-jitter",
        "health_interval": "10s"
      },
      "consumer": {
        "topic": "*",
        "workers": 1,
        "timeout": "150ms",
        "max_rate": 0.5
      },
      "backend": [
        {
          "host": [
            "http://127.0.0.1:8080"
          ],
          "url_pattern": "/__debug/"
        }
      ],
      "extra_config": {
        "async/amqp": {
          "host": "amqp://guest:guest@rabbit:5672",
          "name": "krakend",
          "exchange": "foo",
          "durable": true,
          "delete": false,
          "exclusive": false,
          "no_wait": true,
          "prefetch_count": 5,
          "auto_ack": false,
          "no_local": true
        }
      }
    }
  ],
  "endpoints":[
    {
      "endpoint":"/api/user/register-user/{key}",
      "timeout": "2000ms",
      "method":"POST",
      "backend": [{
        "host": ["amqp://guest:guest@rabbit:5672"],
        "disable_host_sanitize": true,
        "extra_config": {
          "backend/amqp/producer": {
            "name": "queue-1",
            "exchange": "some-exchange",
            "durable": true,
            "delete": false,
            "no_wait": true,
            "no_local": false,
            "routing_key": "#",
            "prefetch_count": 10,
            "prefetch_size": 1024,
            "mandatory": false,
            "immediate": false
          }
        }
      }]
    }
  ]
}

docker-compose up

docker-compose.yml
 ...
  krakend_ce:
    container_name: 'api-gateway'
    image: devopsfaith/krakend:latest
    restart: on-failure
    volumes:
      - ./krakend:/etc/krakend
    ports:
      - "1234:1234"
      - "8080:8080"
      - "8090:8090"
    command: ["run", "-d", "-c", "/etc/krakend/krakend.json"]
    depends_on:
      - rabbitmq

Logs
If applicable, any logs you saw in the console and debugging information

api-gateway
[devopsfaith/krakend:latest](https://github.com/devopsfaith/krakend-ce/issues/new?assignees=&labels=question&template=help-and-questions.md&title=)
RUNNING





Parsing configuration file: /etc/krakend/krakend.json

2022/04/27 10:49:17 KRAKEND ERROR: [SERVICE: Logging] Unable to create the logger: getting the extra config for the krakend-gologging module

2022/04/27 10:49:17 KRAKEND DEBUG: [SERVICE: Gin] Debug enabled

2022/04/27 10:49:17 KRAKEND INFO: Starting the KrakenD instance

2022/04/27 10:49:17 KRAKEND INFO: [SERVICE: Gin] Building the router

2022/04/27 10:49:17 KRAKEND DEBUG: [SERVICE: AsyncAgent][cool-agent] Starting the async agent

2022/04/27 10:49:17 KRAKEND DEBUG: [ENDPOINT: cool-agent] Building the proxy pipe

2022/04/27 10:49:17 KRAKEND DEBUG: [BACKEND: /__debug/] Building the backend pipe

2022/04/27 10:49:17 KRAKEND DEBUG: [ENDPOINT: /api/user/register-user/:key] Building the proxy pipe

2022/04/27 10:49:17 KRAKEND DEBUG: [BACKEND: /] Building the backend pipe

2022/04/27 10:49:17 KRAKEND ERROR: [BACKEND: /][AMQP] Error getting the channel for amqp://guest:guest@rabbit:5672/queue-1: dial tcp 172.24.0.2:5672: connect: connection refused

2022/04/27 10:49:17 KRAKEND DEBUG: [ENDPOINT: /api/user/register-user/:key] Building the http handler

2022/04/27 10:49:17 KRAKEND DEBUG: [ENDPOINT: /api/user/register-user/:key][JWTSigner] Signer disabled

2022/04/27 10:49:17 KRAKEND INFO: [ENDPOINT: /api/user/register-user/:key][JWTValidator] Validator disabled for this endpoint

2022/04/27 10:49:17 KRAKEND INFO: [SERVICE: Gin] Listening on port: 8080

2022/04/27 10:49:18 KRAKEND INFO: [SERVICE: AsyncAgent][AMQP][cool-agent] Starting the consumer

2022/04/27 10:49:18 KRAKEND ERROR: [SERVICE: Asyncagent][cool-agent] building the amqp subscriber: dial tcp 172.24.0.2:5672: connect: connection refused

2022/04/27 10:49:20 KRAKEND INFO: [SERVICE: AsyncAgent][AMQP][cool-agent] Starting the consumer

2022/04/27 10:49:20 KRAKEND ERROR: [SERVICE: Asyncagent][cool-agent] building the amqp subscriber: dial tcp 172.24.0.2:5672: connect: connection refused

2022/04/27 10:49:22 KRAKEND DEBUG: [SERVICE: Telemetry] Registering usage stats for Cluster ID a9SodgjZ2GbNIpO/Et3MPJjSs/QjUYbaSO2b8romk4E=

2022/04/27 10:49:23 KRAKEND INFO: [SERVICE: AsyncAgent][AMQP][cool-agent] Starting the consumer

2022/04/27 10:53:55 KRAKEND ERROR: [ENDPOINT: /api/user/register-user/:key] Post "amqp://guest:***@rabbit:5672/": unsupported protocol scheme "amqp"

[GIN] 2022/04/27 - 10:53:55 | 500 |   13.027833ms |      172.24.0.1 | POST     "/api/user/register-user/123"

[github-actions]

This issue is stale because it has been open 90 days with no activity. Remove stale label or comment or this will be closed in 15 days.

[alombarte]

Planned for KrakenD 2.3 to have retries with different retry strategies

[github-actions]

This issue was marked as resolved a long time ago and now has been automatically locked as there has not been any recent activity after it. You can still open a new issue and reference this link.