Slack branch existence notification #19907

	name: Slack branch existence notification
	on:
	create:
	delete:

	jobs:
	notify:
	name: Notify
	runs-on: ubuntu-latest
	timeout-minutes: 5 # 2022-11-22: Shouldn't take long.
	if: github.event.ref == 'prerelease'

	steps:
	- uses: actions/checkout@v4
	with:
	ref: trunk
	- name: Generate message
	id: message
	run: \|
	source .github/files/gh-funcs.sh

	if [[ "$GITHUB_EVENT_NAME" == 'create' ]]; then
	gh_set_output message "$(
	jq -nc --slurpfile event "$GITHUB_EVENT_PATH" '$event[0] as $e \| {
	icon_emoji: ":lock:",
	text: "Incoming release! Prerelease branch was created by \( $e.sender.login ).",
	blocks: [
	{
	type: "section",
	text: {
	type: "mrkdwn",
	text: ":holdontoyourbutts: Incoming release! Prerelease branch was created by \( $e.sender.login ).",
	},
	}
	],
	}'
	)"
	elif [[ "$GITHUB_EVENT_NAME" == 'delete' ]]; then
	gh_set_output message "$(
	jq -nc --slurpfile event "$GITHUB_EVENT_PATH" '$event[0] as $e \| {
	icon_emoji: ":unlock:",
	text: "Prerelease branch was deleted by \( $e.sender.login ).",
	blocks: [
	{
	type: "section",
	text: {
	type: "mrkdwn",
	text: "Prerelease branch was deleted by \( $e.sender.login ).",
	},
	}
	],
	}'
	)"
	else
	echo "::error::Unknown event \"$GITHUB_EVENT_NAME\""
	exit 1
	fi

	- name: Send message to releases channel
	uses: slackapi/[email protected]
	with:
	channel-id: ${{ secrets.SLACK_RELEASES_CHANNEL }}
	payload: ${{ steps.message.outputs.message }}
	env:
	SLACK_BOT_TOKEN: ${{ secrets.SLACK_TOKEN }}

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