Docker Compose healthcheck example suggests incorrect usage of healthcheck feature

[jennydaman]

Is this a docs issue?

• My issue is about the documentation content or website

Type of issue

Information is incorrect

Description

The documentation says:

For more information on HEALTHCHECK, see the Dockerfile reference.

The Dockerfile reference says:

The command's exit status indicates the health status of the container. The possible values are:

• 0: success - the container is healthy and ready for use
• 1: unhealthy - the container isn't working correctly
• 2: reserved - don't use this exit code

However, the Docker Compose documentation gives this example:

test: ["CMD", "curl", "-f", "http://localhost"]

curl usually produces an exit status other than 1 for errors.

Location

https://docs.docker.com/reference/compose-file/services/#healthcheck

Suggestion

No response

[thaJeztah]

Thanks for reporting; I need to check the implementation (whether it only accepts 1 as exit-code for "unhealthy"), but at least the Dockerfile reference could probably use a bit more wording around the example normalising to 1 for this, and the compose example to be updated accordingly.