> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://buildwithfern.com/learn/llms.txt.

# Sync your AsyncAPI specification

Keeping your AsyncAPI specifications in sync with your codebase is crucial for maintaining accurate SDKs and documentation. Fern provides several automation options to streamline this process.

## GitHub Actions

Use Fern's GitHub Action to automatically update SDKs and docs when your AsyncAPI spec changes:

**`.github/workflows/fern.yml`**

```yaml title=".github/workflows/fern.yml"
name: Fern

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main

jobs:
  fern-check:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repo
        uses: actions/checkout@v4
        
      - name: Check AsyncAPI spec
        uses: fern-api/action@v0
        with:
          command: check
        env:
          FERN_TOKEN: ${{ secrets.FERN_TOKEN }}

  fern-generate:
    runs-on: ubuntu-latest
    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
    steps:
      - name: Checkout repo
        uses: actions/checkout@v4
        
      - name: Generate SDKs and docs
        uses: fern-api/action@v0
        with:
          command: generate
        env:
          FERN_TOKEN: ${{ secrets.FERN_TOKEN }}
```

## Webhook integration

Set up webhooks to trigger SDK generation when your AsyncAPI spec is updated:

**`generators.yml`**

```yaml title="generators.yml" {4-8}
api:
  specs:
    - spec: asyncapi.yml
  github:
    repository: your-org/your-repo
  webhooks:
    - url: https://your-api.com/webhooks/fern
      events: [generate]
  generators:
    - name: fern-typescript-sdk
      version: 0.8.8
      output:
        location: npm
        package-name: "@your-org/sdk"
```

## Auto-sync from source

Configure Fern to automatically pull your AsyncAPI specification from various sources:

### From URL

**`generators.yml`**

```yaml title="generators.yml" {3-4}
api:
  specs:
    - spec: https://api.yourcompany.com/asyncapi.yml
      auto-sync: true
  generators:
    - name: fern-typescript-sdk
      version: 0.8.8
```

### From git repository

**`generators.yml`**

```yaml title="generators.yml" {3-7}
api:
  specs:
    - spec:
        git:
          repository: https://github.com/your-org/api-specs
          path: asyncapi/api.yml
          branch: main
  generators:
    - name: fern-typescript-sdk
      version: 0.8.8
```

## CI/CD integration

### CircleCI

**`.circleci/config.yml`**

```yaml title=".circleci/config.yml" {15-23}
version: 2.1

orbs:
  fern: fernapi/fern@1.0

workflows:
  version: 2
  build-and-test:
    jobs:
      - build
      - test:
          requires:
            - build
      - fern/generate:
          requires:
            - test
          filters:
            branches:
              only: main
          context:
            - fern-context
```

### GitLab CI

**`.gitlab-ci.yml`**

```yaml title=".gitlab-ci.yml" {13-20}
stages:
  - build
  - test
  - generate

variables:
  FERN_TOKEN: $FERN_TOKEN

build:
  stage: build
  script:
    - echo "Building application..."

generate-sdks:
  stage: generate
  image: fernapi/fern:latest
  script:
    - fern generate
  only:
    - main
```

## Scheduled updates

Set up scheduled updates to ensure your SDKs stay current:

**`.github/workflows/scheduled-update.yml`**

```yaml title=".github/workflows/scheduled-update.yml"
name: Scheduled AsyncAPI Update

on:
  schedule:
    - cron: '0 2 * * 1'  # Every Monday at 2 AM UTC
  workflow_dispatch:

jobs:
  update-specs:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout repo
        uses: actions/checkout@v4
        
      - name: Update AsyncAPI specs
        run: |
          curl -o fern/asyncapi/asyncapi.yml https://api.yourcompany.com/asyncapi.yml
          
      - name: Generate with latest spec
        uses: fern-api/action@v0
        with:
          command: generate
        env:
          FERN_TOKEN: ${{ secrets.FERN_TOKEN }}
```

## Monitoring changes

Track changes to your AsyncAPI specification:

**`generators.yml`**

```yaml title="generators.yml" {4-9}
api:
  specs:
    - spec: asyncapi.yml
  change-detection:
    enabled: true
    breaking-changes: error
    notifications:
      slack: ${{ secrets.SLACK_WEBHOOK }}
      email: team@yourcompany.com
  generators:
    - name: fern-typescript-sdk
      version: 0.8.8
```

This ensures that any breaking changes to your AsyncAPI specification are detected and the appropriate team members are notified before the changes are propagated to your SDKs and documentation.

> Automatically sync your AsyncAPI spec changes to keep SDKs and docs up to date