[Pkg-matrix-maintainers] Bug#927181: matrix-synapse: hard to troubleshoot

[Linda Lapinlampi]

Control: tags -1 + moreinfo

On Tue, Apr 16, 2019 at 02:57:45AM +0300, sergio wrote:
> # su matrix-synapse
> $ python3 -m "synapse.app.homeserver" --config-path
> /etc/matrix-synapse/homeserver.yaml --config-path
> /etc/matrix-synapse/conf.d/
> 
> Missing lxml library. This is required for URL preview API.
> 
>     Install by running:
>         sudo apt install python3-lxml

Hi.

This package has "Recommends: python3-lxml" already, and it's not a hard
dependency to run Synapse per se. url_preview_enabled defaults to False
in default homeserver configuration from Debian (according to
debian/homeserver.yaml file).

What would you propose to be fixed in the Debian package? As far as I'm
concerned, upstream makes at least an effort to tell you need to install
python3-lxml if it's missing with url_preview_enabled option enabled.
APT should also install recommended packages by default, unless the
sysadmin makes changes to APT::Install-Recommends option or passes the
--no-install-recommends option to apt install command.