SearXNG: docker

[dalf]

What does this PR do?

SearXNG brand: the docker image

• installs the file in usr/local/searxng (inside the image)
• uses searxng user
• uses the volume /etc/searxng.

searx compatibility:

• If /etc/searx/settings.yml exists, it is copied to /etc/searxng
• If /etc/searx/uwsgi.ini exists, is it ignored (the content requires some updates)
• If /etc/searx/settings.yml or /etc/searx/uwsgi.ini exist:
  • a warning is logged
  • the file /etc/searx/deprecated_volume_read_me.txt is created, and notice the administrator.

The documentation is updated accordingly.

Why is this change important?

See #358

How to test this PR locally?

Author's checklist

Related issues

[unixfox]

I haven't had the time to test this PR but I guess the major test is to install a working Searx container then migrate to a searxng container and see if it still works.

[return42]

• If /etc/searx/settings.yml exists, it is copied to /etc/searxng

Related issue: #401

@dalf should we rebase this PR first .. to get #401 ?

[dalf]

@dalf should we rebase this PR first .. to get #401 ?

In the docker image, SearXNG uses /etc/searxng/settings.yml and falls back to /etc/searx/settings.yml.

But before the application starts, if /etc/searxng/settings.yml doesn't exist then it is copied from /usr/local/searxng/searx/settings.yml ( see dockerfiles/docker-entrypoint.sh ) So the fall back to /etc/searx/settings.yml never happens.

That's why, in this PR /etc/searx/settings.yml is copied to /etc/searxng/settings.yml, in addition /etc/searx/deprecated_volume_read_me.txt contains a warning.

The test is:

• install https://github.com/searx/searx-docker
• ./start.sh
• ./stop.sh
• change ./searx/settings.yml ( the instance name for example ).
• change the docker image from searx/searx to searxng/searxng.
• ./start.sh
• check the instance name is still changed.
• check there is ./searx/deprecated_volume_read_me.txt.

[dalf]

It works on a new VM as expected with only one issue: in settings.yml, brand.new_issue_url is required, so SearXNG doesn't start. Once brand.new_issue_url is set, everything is okay.