feat: build, sign and publish registries #5736

	name: CI

	on:
	pull_request:
	push:
	branches:
	- "feature/**"

	jobs:
	publish:
	runs-on: ubuntu-latest
	steps:
	- name: Decision to Publish
	id: decisions
	run: \|
	# Secrets cannot be used in conditionals, so this is our dance:
	# https://github.com/actions/runner/issues/520
	if [[ -n "${{ secrets.SNAPCRAFT_STORE_CREDENTIALS }}" ]]; then
	echo PUBLISH=true >> $GITHUB_OUTPUT
	else
	echo PUBLISH= >> $GITHUB_OUTPUT
	fi

	- if: steps.decisions.outputs.PUBLISH == 'true'
	name: Checkout Snapcraft
	uses: actions/checkout@v4
	with:
	# Fetch all of history so Snapcraft can determine its own version from git.
	fetch-depth: 0

	- if: steps.decisions.outputs.PUBLISH == 'true'
	uses: canonical/action-build@v1
	name: Build Snapcraft Snap
	id: build
	with:
	snapcraft-channel: latest/candidate

	- if: steps.decisions.outputs.PUBLISH == 'true'
	name: Verify Snapcraft Snap
	run: \|
	# Make sure it is installable.
	sudo snap install --dangerous --classic ${{ steps.build.outputs.snap }}

	- name: Get branch name
	id: vars
	run: \|
	if [[ "${{ github.event_name }}" == "pull_request" ]]
	then
	echo "branch=pr-${{ github.event.number }}" >> "$GITHUB_OUTPUT"
	else
	branch=$(echo ${GITHUB_REF#refs//} \| sed -e 's\|feature/$.$\|\1\|')
	echo "branch=$branch" >> "$GITHUB_OUTPUT"
	fi

	- name: Publish feature branch to edge/${{ steps.vars.outputs.branch }}
	if: steps.decisions.outputs.PUBLISH == 'true'
	uses: canonical/action-publish@v1
	env:
	SNAPCRAFT_STORE_CREDENTIALS: ${{ secrets.SNAPCRAFT_STORE_CREDENTIALS }}
	with:
	snap: ${{ steps.build.outputs.snap }}
	release: edge/${{ steps.vars.outputs.branch }}

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