This PR adds the LogChannelBootstrapper to provide tenant-specific
logging configuration. The bootstrapper automatically configures storage
path channels to use tenant-specific directories (NOTE: for this to work
correctly, the bootstrapper has to run AFTER
FilesystemTenancyBootstrapper, otherwise, the logs still won't be
separated, unless you use overrides) and supports custom channel
overrides for custom logging scenarios -- mapping tenant properties to
the channel config, or using custom closures an array with the logging
config, e.g. for making the slack channel (that's not handled by the
bootstrapper by default) tenant-specific.
The bootstrapper first modifies the channel config, then forgets the
channel from LogManager so that on the next logging attempt, the channel
is re-resolved with the modified config. Otherwise, the channel would
just use the initial config **if the channel was resolved before**. If
the channel wasn't resolved before, it'll always be resolved with the
updated (tenant) config, unless the configuration fails. In that case,
the config will be reverted (the central config will be restored) and
the error will be logged using the original channel.
When using a channel stack, the `stack` channel itself also has to be
forgotten, since the LogManager could retain e.g. the original `stack`
channel's webhook URL, while the underlying `slack` channel would use
the updated one, and while logging, the app would actually use the
initial webhook URL instead of the updated one (encountered this issue
while testing).
Note that **all** channels in `$storagePathChannels` and
`$channelOverrides` are affected.
Also, adding `'attachment' => 'false'` to the slack channel's config
makes the slack channel work with Discord webhooks (just a cool thing we
figured out whlle testing the bootstrapper).
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Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Samuel Štancl <samuel@archte.ch>
