Re: [PATCH] tests/avocado: Cancel BootLinux tests in case there is no free port

[Beraldo Leal <bleal@redhat.com>]

Hi, Thomas, sorry for the late reply, I was in PTO.

Just in case it is still needed:

On Mon, Feb 28, 2022 at 12:43:25PM +0100, Thomas Huth wrote:
> The BootLinux tests are currently failing with an ugly python
> stack trace on my RHEL8 system since they cannot get a free port
> (likely due to the firewall settings on my system). Let's properly
> check the return value of find_free_port() instead and cancel the
> test gracefully if it cannot get a free port.
> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  Unfortunately, it still takes > 70 seconds for each and every
>  tests from tests/avocado/boot_linux.py to get canceled, so
>  tests/avocado/boot_linux.py still renders "make check-avocado"
>  for me pretty unusable... looking at the implementation of
>  find_free_port() in Avocado, I wonder whether there isn't a
>  better way to get a free port number in Python? Brute-forcing
>  all ports between 1024 and 65536 seems just quite cumbersome
>  to me...

This is something that also bothers me with this method, and maybe we
could get a free port using something like this:

```
with socket() as s: 
    s.bind(('',0)) 
    port = s.getsockname()[1]
```  

I haven't benchmarked both solutions yet nor looked at socket module
code, but I just created an issue[1] on Avocado's side so that we can
evaluate alternatives.

[1] - https://github.com/avocado-framework/avocado/issues/5273

>  tests/avocado/avocado_qemu/__init__.py | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/tests/avocado/avocado_qemu/__init__.py b/tests/avocado/avocado_qemu/__init__.py
> index 75063c0c30..9b056b5ce5 100644
> --- a/tests/avocado/avocado_qemu/__init__.py
> +++ b/tests/avocado/avocado_qemu/__init__.py
> @@ -603,6 +603,8 @@ def prepare_cloudinit(self, ssh_pubkey=None):
>          try:
>              cloudinit_iso = os.path.join(self.workdir, 'cloudinit.iso')
>              self.phone_home_port = network.find_free_port()
> +            if not self.phone_home_port:
> +                self.cancel('Failed to get a free port')
>              pubkey_content = None
>              if ssh_pubkey:
>                  with open(ssh_pubkey) as pubkey:

In any case, this LGTM.

Reviewed-by: Beraldo Leal <bleal@redhat.com>

--
Beraldo