How to test modified shepherd services

How to test modified shepherd services

[Nathan Dehnel]

I modified a shepherd service to accept a new field from config.scm
and I was wondering how to test that it works correctly. Do I need to
make a VM from my modified guix repo with pre-inst-env?

Re: How to test modified shepherd services

[raingloom]

On Sun, 19 Dec 2021 16:47:07 -0600
Nathan Dehnel <ncdehnel@gmail.com> wrote:

> I modified a shepherd service to accept a new field from config.scm
> and I was wondering how to test that it works correctly. Do I need to
> make a VM from my modified guix repo with pre-inst-env?
> 

That's probably the best way, it's how I was testing the yggdrasil
service. Definitely do not reconfigure without first testing it in a VM
or container or something.

Word of warning: shepherd is not very forthcoming with logs. You might
want to add some extra logging and redirect output to a file.

Re: How to test modified shepherd services

[Attila Lendvai]

i have just finished my first Guix service. for now it's a PR for that other channel, so i'll copy-paste some stuff from it:

Run with something like this:

$(guix system --no-graphic vm path/to/swarm.scm) -m 2048

$(./pre-inst-env guix system --no-graphic vm /path/to/swarm.scm) -m 2048

this will build and boot an operating-system object in a Qemu VM, in the same terminal.

the file should return a simple-operating-system object, optionally wrapped into a marionette-operating-system if you also want to write/run automated tests.

i'll send you the link to the actual code in a private email.

- attila
PGP: 5D5F 45C7 DFCD 0A39

Re: How to test modified shepherd services

[Nathan Dehnel]

Thanks, that worked.

On Mon, Dec 20, 2021 at 4:00 AM Attila Lendvai <attila@lendvai.name> wrote:
>
> i have just finished my first Guix service. for now it's a PR for that other channel, so i'll copy-paste some stuff from it:
>
> Run with something like this:
>
> $(guix system --no-graphic vm path/to/swarm.scm) -m 2048
>
> $(./pre-inst-env guix system --no-graphic vm /path/to/swarm.scm) -m 2048
>
> this will build and boot an operating-system object in a Qemu VM, in the same terminal.
>
> the file should return a simple-operating-system object, optionally wrapped into a marionette-operating-system if you also want to write/run automated tests.
>
> i'll send you the link to the actual code in a private email.
>
> - attila
> PGP: 5D5F 45C7 DFCD 0A39
>

Re: How to test modified shepherd services

[Simon South]

Nathan Dehnel <ncdehnel@gmail.com> writes:
> I modified a shepherd service to accept a new field from config.scm
> and I was wondering how to test that it works correctly.

Assuming this is an existing Guix service, it's probably easiest to
update the corresponding system test suite under gnu/tests (if
necessary) to reflect your change, then run the suite with "make
check-system" (setting "TESTS" to limit it to the service in question)
to make sure everything works the way you expect.

If you're planning on contributing the change to Guix it would be good
to submit it along with an updated test suite anyway.

The Guix manual has a bit of information about this in Section 2.3,
"Running the Test Suite":

https://guix.gnu.org/en/manual/en/html_node/Running-the-Test-Suite.html#Running-the-Test-Suite

-- 
Simon South
simon@simonsouth.net

Re: How to test modified shepherd services

[Maxim Cournoyer]

Hello,

Simon South <simon@simonsouth.net> writes:

> Nathan Dehnel <ncdehnel@gmail.com> writes:
>> I modified a shepherd service to accept a new field from config.scm
>> and I was wondering how to test that it works correctly.
>
> Assuming this is an existing Guix service, it's probably easiest to
> update the corresponding system test suite under gnu/tests (if
> necessary) to reflect your change, then run the suite with "make
> check-system" (setting "TESTS" to limit it to the service in question)
> to make sure everything works the way you expect.
>
> If you're planning on contributing the change to Guix it would be good
> to submit it along with an updated test suite anyway.
>
> The Guix manual has a bit of information about this in Section 2.3,
> "Running the Test Suite":
>
> https://guix.gnu.org/en/manual/en/html_node/Running-the-Test-Suite.html#Running-the-Test-Suite

+1.  System tests are the best way to validate system services.  You'll
save time by writing/extending one.

Maxim