proxy-server: change --delete-existing-uds-file default to true.

[jkh52]

This is followup from discusssion at #476

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[jkh52]

/assign @guettli
/assign @cheftako

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[cheftako]

/hold OK with the change as long as we discuss it in the public Konnectivity server meeting first.

[ipochi]

@jkh52 @cheftako

Technical reasons aside for wanting to set the default as true. Just in general I feel that if you want to set any bool flag, you set it explicitly such as (--delete-exisiting-uds-file), if it is not set then the default should be assumed to be false.

Wouldn't it make setting the flag --delete-existing-uds-file redundant if the default is true.

[guettli]

@ipochi

Wouldn't it make setting the flag --delete-existing-uds-file redundant if the default is true.

I had the same idea on my mind. I think there is no reason to not delete the file. An alternative would be to make all the things which systemd does to ensure servers don't get accidentaly created twice. But this makes no sense, since this script gets run by systemd (at least in the places I am aware of).

[jkh52]

@ipochi

Wouldn't it make setting the flag --delete-existing-uds-file redundant if the default is true.

I had the same idea on my mind. I think there is no reason to not delete the file. An alternative would be to make all the things which systemd does to ensure servers don't get accidentaly created twice. But this makes no sense, since this script gets run by systemd (at least in the places I am aware of).

If we go this route (let's say option B), we should mark the flag deprecated for some time: example.

I only slightly prefer option A (this PR currently), and if I'm in the minority I'll switch to B. @cheftako do you have an opinion?

It does seem true that getUdsListener cannot possibly succeed if udsName already exists.

[elmiko]

/unhold

[jkh52]

This was discussed in the OSS biweekly this morning: Meeting Notes. From discussion: a cluster administrator running multiple proxy servers on a single host could possibly want to manage UDS file cleanup in some careful or particular way. There was unanimous consensus to go forward with keeping the flag rather than hardcoding the cleanup.

[cheftako]

/lgtm