We have lots of builds running all day long, but we don’t want to flood the same Slack channel with build results for every branch. Here’s how we avoid the noise and make sure only the appropriate channels or individuals get notified.
First, we can add an app environment variable that defines which are the “main” (i.e. non-development) branches, using a simple regular expression:
In this example, it will provide us with the condition we check in order to choose the notification target.
Then, we add a “Script” step to our workflow, somewhere towards the end:
In this step, we can test the condition (are we on a “main” branch?), choose the appropriate Slack target, and finally use envman to export it as an environment variable that can be used later:
#!/usr/bin/env bash
set -ex
if [[ $BITRISE_GIT_BRANCH =~ ^$MAIN_BRANCHES_REGEXP$ ]]; then
SLACK_TARGET="#myapp_ci_builds"
else
SLACK_TARGET="@$(git log -1 --format=%ae | cut -d @ -f 1)"
fi
envman add --key SLACK_TARGET --value "$SLACK_TARGET"
Note that the BITRISE_GIT_BRANCH environment variable is available generally only when the workflow is triggered by a push event. One can easily adapt the script for pull requests, tags, etc. by modifying or adding conditions to check the relevant environment variables.
In the above script, if there was a push to a “main” branch, then we’ll want to notify a dedicated channel. Otherwise, we assume the last commit author is the relevant notification target, and we transform their email address into their Slack username. (This works in my organization, but it might be less straightforward for others.) Finally, we use envman to export the variable.
Finally, we insert the “Slack message” step and simply set the “target” to $SLACK_TARGET:
In your bitrise.yml, it should look something like this:
# ... other stuff
- script:
title: Set Slack target
is_skippable: true
inputs:
- content: |-
#!/usr/bin/env bash
set -ex
if [[ $BITRISE_GIT_BRANCH =~ ^$MAIN_BRANCHES_REGEXP$ ]]; then
SLACK_TARGET="#myapp_ci_builds"
else
SLACK_TARGET="@$(git log -1 --format=%ae | cut -d @ -f 1)"
fi
envman add --key SLACK_TARGET --value "$SLACK_TARGET"
is_always_run: true
- slack:
inputs:
- channel: "$SLACK_TARGET"
# ... other stuff
Note the is_skippable: true on the script step, which you might want to add manually to keep any unexpected failure at this step from affecting the overall build status. (Thanks for the tip, @koral!)
Hope this helps someone, and feel free to comment if you find any improvements. 
(Also, be sure to vote for or follow the relevant feature requests if you want Bitrise to allow us to notify multiple committers/targets at once, or the person who manually launched the build!)
Cheers!