Add sentinel error for no servers left in the backend pool #64

	name: Go Matrix

	on:
	push:
	branches:
	- master
	pull_request:

	jobs:

	cross:
	name: Go
	runs-on: ${{ matrix.os }}
	env:
	CGO_ENABLED: 0

	strategy:
	matrix:
	go-version: [ '1.19', '1.20', 1.x ]
	os: [ubuntu-latest, macos-latest]
	# TODO ignore windows but need to be added in the future
	# os: [ubuntu-latest, macos-latest, windows-latest]

	steps:
	# https://github.com/marketplace/actions/setup-go-environment
	- name: Set up Go ${{ matrix.go-version }}
	uses: actions/setup-go@v2
	with:
	go-version: ${{ matrix.go-version }}

	# https://github.com/marketplace/actions/checkout
	- name: Checkout code
	uses: actions/checkout@v2

	# https://github.com/marketplace/actions/cache
	- name: Cache Go modules
	uses: actions/cache@v2
	with:
	# In order:
	# * Module download cache
	# * Build cache (Linux)
	# * Build cache (Mac)
	# * Build cache (Windows)
	path: \|
	~/go/pkg/mod
	~/.cache/go-build
	~/Library/Caches/go-build
	%LocalAppData%\go-build
	key: ${{ runner.os }}-${{ matrix.go-version }}-go-${{ hashFiles('**/go.sum') }}
	restore-keys: \|
	${{ runner.os }}-${{ matrix.go-version }}-go-

	- name: Test
	run: go test -v -cover ./...

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