Update actions/cache action to v4 #40

	name: CI

	on:
	push:
	branches:
	- main
	pull_request:
	branches:
	- main
	jobs:
	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4

	- name: Setup Node.js environment
	uses: actions/setup-node@v4
	with:
	node-version: "14.x"

	- name: Get yarn cache directory path
	id: yarn-cache-dir-path
	run: echo "::set-output name=dir::$(yarn cache dir)"

	- name: Cache yarn cache
	uses: actions/cache@v4
	id: cache-yarn-cache
	with:
	path: ${{ steps.yarn-cache-dir-path.outputs.dir }}
	key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
	restore-keys: \|
	${{ runner.os }}-yarn-

	- name: Cache node_modules
	id: cache-node-modules
	uses: actions/cache@v4
	with:
	path: node_modules
	key: ${{ runner.os }}-${{ matrix.node-version }}-nodemodules-${{ hashFiles('**/yarn.lock')
	}}
	restore-keys: \|
	${{ runner.os }}-${{ matrix.node-version }}-nodemodules-

	- name: Install dependencies
	run: yarn install --frozen-lockfile

	- name: Build and test frontend
	run: yarn build

	- name: Check for backend
	id: check-for-backend
	run: \|
	if [ -f "Magefile.go" ]
	then
	echo "::set-output name=has-backend::true"
	fi

	- name: Setup Go environment
	if: steps.check-for-backend.outputs.has-backend == 'true'
	uses: actions/setup-go@v5
	with:
	go-version: "1.15"

	- name: Test backend
	if: steps.check-for-backend.outputs.has-backend == 'true'
	uses: magefile/mage-action@v3
	with:
	version: latest
	args: coverage

	- name: Build backend
	if: steps.check-for-backend.outputs.has-backend == 'true'
	uses: magefile/mage-action@v3
	with:
	version: latest
	args: buildAll

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