Re: pre-release [PATCH] git-service [v2]

[Alex Kost]

ng0 (2016-08-11 18:55 +0300) wrote:

> ng0 <address@hidden> writes:
>
>> As I wrote yesterday in freenode, disregard this patch. I
>> succeeded and currently am debugging the VM.
>
> I had it working at some point, but only to find out that I am passing
> something wrong in the service.
> Can someone take a look at this service and help me out?

Hi, I didn't try this service, but I see 2 mistakes in the code.

[...]
> +(define (git-shepherd-service config)
> +  "Return a <shepherd-service> for git with CONFIG."
> +  (define git (git-configuration-git config))
> +
> +  (define git-command
> +    #~(list
> +       (string-append #$git "/bin/git") "daemon" "--syslog"
> +       "--informative-errors"
> +       "--port=" (number->string (git-configuration-port config))
> +       "--base-path=" (git-configuration-base-path config)))

1. This should be:

          "--port=" #$(number->string (git-configuration-port config))
          "--base-path=" #$(git-configuration-base-path config)))

Note ‘#$’ before expressions.  Without it, these expressions will stay
the same in the final making service code (see below).

> +  (define requires
> +    '(networking syslogd))
> +
> +  (list (shepherd-service
> +         (documentation "Git daemon server for git repositories")
> +         (requirement requires)
> +         (provision '(git))
> +         (start #~(make-forkexec-constructor address@hidden))

2. This should be:

            (start #~(make-forkexec-constructor #$git-command))

Note ‘#$@ → #$’.  With #$@, the list (I mean git-command) is "spliced",
so the result in "/gnu/store/...-shepherd-git.scm" will be:

(make <service>
  ...
  #:start
  (make-forkexec-constructor list
                             (string-append "/gnu/store/…" "/bin/git")
                             "daemon" "--syslog" "--informative-errors"
                             "--port=" (number->string
                                        (git-configuration-port config))
                             "--base-path="
                             (git-configuration-base-path config))
  ...)

While it should be: (make-forkexec-constructor (list ...))

Also I have a question about the final command to start git daemon.  It
would look like this:

  git daemon --syslog --informative-errors --port=9418 
--base-path=/var/git/repositories

Is it intentional?  I mean "/var/git/repositories" does not exist and
you don't create it at activation time, so the service (with the default
'base-path') will fail anyway.

But you create "/var/run/git-daemon".  Is it really needed?  I know
nothing about "git daemon", but IIUC it starts successfully without this
directory.

-- 
Alex