Configuring CI Using GitHub Actions and Nx

GitHub can track the last successful run on the main branch and use this as a reference point for the BASE. The Nx Set SHAs provides a convenient implementation of this functionality which you can drop into your existing CI config. To understand why knowing the last successful build is important for the affected command, check out the in-depth explanation in Actions's docs.

Below is an example of a GitHub setup for an Nx workspace - building and testing only what is affected. For more details on how the action is used, head over to the official docs.

1name: CI 2on: 3 push: 4 branches: 5 - main 6 pull_request: 7 8jobs: 9 main: 10 runs-on: ubuntu-latest 11 steps: 12 - uses: actions/checkout@v3 13 with: 14 fetch-depth: 0 15 - uses: nrwl/nx-set-shas@v3 16 - run: npm ci 17 18 - run: npx nx format:check 19 - run: npx nx affected -t lint --parallel=3 20 - run: npx nx affected -t test --parallel=3 21 - run: npx nx affected -t build --parallel=3 22

The pr and main jobs implement the CI workflow. Setting timeout-minutes is needed only if you have very slow tasks.

Tracking the origin branch

If you're using this action in the context of a branch you may need to add run: "git branch --track main origin/main" before running the nx affected command since origin/main won't exist.

Distributed CI with Nx Cloud

Read more about Distributed Task Execution (DTE).

1name: CI 2on: 3 push: 4 branches: 5 - main 6 pull_request: 7 8jobs: 9 main: 10 name: Nx Cloud - Main Job 11 uses: nrwl/ci/.github/workflows/nx-cloud-main.yml@v0.13.0 12 with: 13 number-of-agents: 3 14 parallel-commands: | 15 npx nx-cloud record -- npx nx format:check 16 parallel-commands-on-agents: | 17 npx nx affected -t lint --parallel=3 & npx nx affected -t test --parallel=3 --configuration=ci & npx nx affected -t build --parallel=3 18 19 agents: 20 name: Nx Cloud - Agents 21 uses: nrwl/ci/.github/workflows/nx-cloud-agents.yml@v0.13.0 22 with: 23 number-of-agents: 3 24

You can also use our ci-workflow generator to generate the workflow file.

Custom distributed CI with Nx Cloud

Our reusable GitHub workflow represents a good set of defaults that works for a large number of our users. However, reusable GitHub workflows come with their limitations.

If the existing workflow doesn't satisfy your needs you should create your custom workflow. This is what the above config roughly encapsulates:

1name: CI 2on: 3 push: 4 branches: 5 - main 6 pull_request: 7 8env: 9 NX_CLOUD_DISTRIBUTED_EXECUTION: true # this enables DTE 10 NX_CLOUD_DISTRIBUTED_EXECUTION_AGENT_COUNT: 3 # expected number of agents 11 NX_BRANCH: ${{ github.event.number || github.ref_name }} 12 NX_CLOUD_ACCESS_TOKEN: ${{ secrets.NX_CLOUD_ACCESS_TOKEN }} 13 NPM_TOKEN: ${{ secrets.NPM_TOKEN }} # this is needed if our pipeline publishes to npm 14 15jobs: 16 main: 17 name: Nx Cloud - Main Job 18 runs-on: ubuntu-latest 19 steps: 20 - uses: actions/checkout@v3 21 name: Checkout [Pull Request] 22 if: ${{ github.event_name == 'pull_request' }} 23 with: 24 # By default, PRs will be checked-out based on the Merge Commit, but we want the actual branch HEAD. 25 ref: ${{ github.event.pull_request.head.sha }} 26 # We need to fetch all branches and commits so that Nx affected has a base to compare against. 27 fetch-depth: 0 28 29 - uses: actions/checkout@v3 30 name: Checkout [Default Branch] 31 if: ${{ github.event_name != 'pull_request' }} 32 with: 33 # We need to fetch all branches and commits so that Nx affected has a base to compare against. 34 fetch-depth: 0 35 36 # Set node/npm/yarn versions using volta 37 - uses: volta-cli/action@v4 38 with: 39 package-json-path: '${{ github.workspace }}/package.json' 40 41 - name: Use the package manager cache if available 42 uses: actions/cache@v3 43 with: 44 path: ~/.npm 45 key: ${{ runner.os }}-${{ hashFiles('**/package-lock.json') }} 46 restore-keys: | 47 ${{ runner.os }}- 48 49 - name: Install dependencies 50 run: npm ci 51 52 - name: Initialize the Nx Cloud distributed CI run 53 run: npx nx-cloud start-ci-run 54 55 - name: Run commands in parallel 56 run: | 57 pids=() 58 # list of commands to be run on main has env flag NX_CLOUD_DISTRIBUTED_EXECUTION set to false 59 NX_CLOUD_DISTRIBUTED_EXECUTION=false npx nx-cloud record -- npx nx format:check & pids+=($!) 60 61 # list of commands to be run on agents 62 npx nx affected -t lint --parallel=3 & 63 pids+=($!) 64 65 npx nx affected -t test --parallel=3 & 66 pids+=($!) 67 68 npx nx affected -t build --parallel=3 & 69 pids+=($!) 70 71 # run all commands in parallel and bail if one of them fails 72 for pid in ${pids[*]}; do 73 if ! wait $pid; then 74 exit 1 75 fi 76 done 77 78 exit 0 79 80 - name: Stop all running agents for this CI run 81 # It's important that we always run this step, otherwise in the case of any failures in preceding non-Nx steps, the agents will keep running and waste billable minutes 82 if: ${{ always() }} 83 run: npx nx-cloud stop-all-agents 84 85 agents: 86 name: Agent ${{ matrix.agent }} 87 runs-on: ubuntu-latest 88 strategy: 89 matrix: 90 agent: [1, 2, 3] 91 steps: 92 - name: Checkout 93 uses: actions/checkout@v3 94 95 # Set node/npm/yarn versions using volta 96 - uses: volta-cli/action@v4 97 with: 98 package-json-path: '${{ github.workspace }}/package.json' 99 100 - name: Use the package manager cache if available 101 uses: actions/cache@v3 102 with: 103 path: ~/.npm 104 key: ${{ runner.os }}-${{ hashFiles('**/package-lock.json') }} 105 restore-keys: | 106 ${{ runner.os }}- 107 108 - name: Install dependencies 109 run: npm ci 110 111 - name: Start Nx Agent ${{ matrix.agent }} 112 run: npx nx-cloud start-agent 113 env: 114 NX_AGENT_NAME: ${{ matrix.agent }} 115