fix(slack): channel api deprecated

[dcshiman]

Slack api https://slack.com/api/channels.* is deprecated see:
Deprecating early methods in favor of the Conversations API
All new slack apps created after June 10th, 2020 will give error, which
creates issue for on premise sentry.

This commit fixes the issue by adding slack.legacy-app=(true/false) to sentry.yml
config so that it continues support for legacy slack apps while new apps
can toggle this option for new slack API support

Resolves: #7897

[hgajjar]

This issue is preventing us from using Sentry effectively, as we can't get slack notifications.
Could someone from core team please review this PR, help to fix the failing builds and get it merged?

[scefali]

@dcshiman Thanks for making this PR! This change definitely needed to be made. This looks good to me but I will test it out locally tomorrow to make sure it works as expected.

[dcshiman]

@scefali thanks, I forked from 10.0.0 initially as we run this version on our on premise. However when i rebased onto master i saw slackV2 implemented with still using the old APIs. I guess its for v20.0.0 for which i am unable to start up the development environment on ubuntu so couldn't run a manual test but successfully tested on 10.0.0

[scefali]

Tested on my machine, looks good!

[hgajjar]

Thank you for merging this @scefali , when can we expect a release with this fix?

[BYK]

Hi @hgajjar, all commits that land on master get available for on-premise as soon as the docker images are built. This fix seems to be out: https://hub.docker.com/r/getsentry/sentry/tags?page=1&name=cc9f7d1

If you are looking for a tagged release, looks like this fix missed the train for our 20.6.0 release so you can expect it to be in 20.7.0 (releasing on July 15th) or maybe in a 20.6.1 patch release if we ever release one.

You can read more about our new release schedule at https://blog.sentry.io/2020/06/22/self-hosted-sentry-switching-to-calver/

[phyzical]

can confirm this as working on latest master of onpremise with the new integration process but requires this to be added to config.yml, i will open a pr to add this incase it was missed.

slack.legacy-app: False

[dcshiman]

can confirm this as working on latest master of onpremise with the new integration process but requires this to be added to config.yml, i will open a pr to add this incase it was missed.

slack.legacy-app: False
@phyzical slack.legacy-app: false needs to be added to the config, i missed it out.

shouldn't we include a doc's page for this ? so far I see only this post as a guide or is there docs which I am not aware of ?

[phyzical]

there is https://develop.sentry.dev, infact upon closer inspection it looks like we just need to fork to add a section for slack in the integrations section.

ill do that later tonight probably :)

Edit: done 👍

[caseyduquettesc]

If anyone is using 9.1.2 on-premise and building from source, I back-ported this change as a patch. Our Slack integration works now. I also threw in the list cursor change to scan large channel lists in pages.

https://gist.github.com/caseyduquettesc/22f9b7ba401adc480e8ca739c23c79b4