feat(consumer): support multiple balance strategies #31

	---
	name: CI

	on: [push, pull_request]

	jobs:
	test:
	name: Go ${{ matrix.go-version }} with Kafka ${{ matrix.kafka-version }} on Ubuntu
	runs-on: ubuntu-latest
	# We want to run on external PRs, but not on our own internal PRs as they'll be run
	# by the push to the branch.
	if: github.event_name == 'push' \|\| github.event.pull_request.head.repo.full_name != github.repository
	strategy:
	fail-fast: false
	matrix:
	go-version: [1.16.x, 1.17.x]
	kafka-version: [2.7.1, 2.8.1, 3.0.0]
	platform: [ubuntu-latest]

	env:
	DEBUG: true
	GOFLAGS: -trimpath
	KAFKA_VERSION: ${{ matrix.kafka-version }}

	steps:
	- uses: actions/checkout@v2

	- name: Setup Go
	uses: actions/setup-go@v2
	with:
	go-version: ${{ matrix.go-version }}

	- name: Get Go environment
	id: go-env
	run: \|
	echo "::set-output name=cache::$(go env GOCACHE)"
	echo "::set-output name=modcache::$(go env GOMODCACHE)"

	- name: Set up cache
	uses: actions/cache@v2
	with:
	path: \|
	${{ steps.go-env.outputs.cache }}
	${{ steps.go-env.outputs.modcache }}
	key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
	restore-keys: \|
	${{ runner.os }}-go-

	- name: Install dependencies
	run: \|
	curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh \| sh -s -- -b $(go env GOPATH)/bin v1.42.1
	export REPOSITORY_ROOT=${GITHUB_WORKSPACE}

	- name: Run test suite
	run: make test_functional

	- name: Run linter
	run: make lint

Provide feedback