agent: backend detection do not work

[Seishirou101]

Component

agent

Describe the bug

When updated to the latest image of the woodpecker-agent, d8daf87ccbb1 as of 7 hours ago, my agent no longer is able to connect to backend engine. Last used image was image pulled at 2021-11-25T12:32:10

System Info

Version:next-5e6b38e0

woodpecker-server:
    image: woodpeckerci/woodpecker-server:latest
    container_name: woodpecker-server
    networks:
      - t2_proxy
      - woodpecker
    volumes:
      - $DOCKERDIR/woodpecker:/var/lib/woodpecker/
    environment:
      - WOODPECKER_OPEN=true
      - WOODPECKER_HOST=xxxx
      - WOODPECKER_GITEA=true
      - WOODPECKER_GITEA_URL=xxx
      - WOODPECKER_GITEA_CLIENT=xxxx
      - WOODPECKER_GITEA_SECRET=xxxx
      - WOODPECKER_AGENT_SECRET=xxxx
    labels:
      - "traefik.enable=true"
      - "diun.enable=true"
      - "flame.type=application" # "app" works too
      - "flame.name=woodpecker"
      # HTTP Routers
      - "traefik.http.routers.woodpecker-rtr.entrypoints=https"
      - "traefik.http.routers.woodpecker-rtr.rule=Host(`woodpecker.$DOMAINNAME`)"
      ## Middlewares
      - "traefik.http.routers.woodpecker-rtr.middlewares=chain-authelia@file"
      ## HTTP Services
      - "traefik.http.routers.woodpecker-rtr.service=woodpecker-svc"
      - "traefik.http.services.woodpecker-svc.loadbalancer.server.port=8000"

  woodpecker-agent:
    image: woodpeckerci/woodpecker-agent:latest
    container_name: woodpecker-agent
    command: agent
    restart: always
    networks:
      - woodpecker
    depends_on:
      - woodpecker-server
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock"
    environment:
      - WOODPECKER_SERVER=woodpecker-server:9000
      - WOODPECKER_AGENT_SECRET=xxxx

Additional context

021-11-26T19:13:50.956301366Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:50Z","message":"cannot find backend engine 'auto-detect'"}
2021-11-26T19:13:51.485319646Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:51Z","message":"cannot find backend engine 'auto-detect'"}
2021-11-26T19:13:52.012249226Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:52Z","message":"cannot find backend engine 'auto-detect'"}
2021-11-26T19:13:52.754148047Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:52Z","message":"cannot find backend engine 'auto-detect'"}
2021-11-26T19:13:53.869578042Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:53Z","message":"cannot find backend engine 'auto-detect'"}
2021-11-26T19:13:55.818519427Z {"level":"error","error":"Can't detect an avivable backend engine","time":"2021-11-26T19:13:55Z","message":"cannot find backend engine 'auto-detect'"}

Validations

• [X] Read the Contributing Guidelines.
• [X] Read the docs.
• [X] Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• [X] Check that this is a concrete bug. For Q&A join our Discord Chat Server.

[6543]

regression of #463 cc @anbraten

[6543]

@Seishirou101 workaround set WOODPECKER_BACKEND=docker for agent :)

[Seishirou101]

Copy that! I will try that out when I get home