Slack integration

[lkysow]

No description provided.

[codecov-io]

Codecov Report

Merging #199 into master will increase coverage by 0.37%.
The diff coverage is 69.34%.

@@            Coverage Diff             @@
##           master     #199      +/-   ##
==========================================
+ Coverage   63.54%   63.91%   +0.37%     
==========================================
  Files          35       38       +3     
  Lines        1986     2123     +137     
==========================================
+ Hits         1262     1357      +95     
- Misses        683      716      +33     
- Partials       41       50       +9

Impacted Files	Coverage Δ
cmd/server.go	76.72% <ø> (ø)	⬆️
server/events/apply_executor.go	0% <0%> (ø)	⬆️
server/events/webhooks/slack_client.go	100% <100%> (ø)
server/server.go	75.21% <20%> (-3.72%)	⬇️
server/events/webhooks/slack.go	57.14% <57.14%> (ø)
server/events/webhooks/webhooks.go	67.56% <67.56%> (ø)

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[codec]

@lkysow just wondering, shouldn't this PR also include the vendored dependencies and updated Gopkg.lock?

[lkysow]

@codec right you are, fixed in #202. I have no idea how that passed CI...

[codec]

Circle CI always fetches them. Might be a bad idea: https://github.com/hootsuite/atlantis/blob/master/.circleci/config.yml#L13

[nadavshatz]

Great stuff guys - if you include some info around how to use/set-this-up I can open a PR with changes to the Readme.

Cheers

[lkysow]

@nadavshatz yep, tracking that in #200. I found a couple things we need to fix first. Right now, we need the slack bot user to join the channel before it can post messages to it so need to add that.