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Hi <@ULVA73B9P>, I have a github actions setup for...
# ask-marvin
a
Hi @Marvin, I have a github actions setup for deploying prefect flows using 
prefect deploy -f prefect.yaml
. How do I go about setting up docker image build caching in my github actions?
m
To improve the efficiency of your Docker builds in GitHub Actions, you can utilize Docker layer caching. This technique stores layers of your image in a cache so they don't need to be rebuilt every time, which can significantly speed up subsequent builds. Here's a general approach to setting up Docker image build caching in GitHub Actions: 1. Use GitHub's Cache Action: GitHub provides a cache action that you can use to cache layers between jobs. You'll store the hash of your Dockerfile and any files needed by your build as part of the cache key. 2. Example Workflow File: Here's a simplified workflow to illustrate the approach:
Copy code
yaml
   name: CI

   on:
     push:
       branches:
         - main

   jobs:
     build:
       runs-on: ubuntu-latest

       steps:
       - name: Checkout code
         uses: actions/checkout@v2

       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v1

       - name: Cache Docker layers
         uses: actions/cache@v2
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ github.sha }}
           restore-keys: |
             ${{ runner.os }}-buildx-

       - name: Build and Push Docker image
         uses: docker/build-push-action@v2
         with:
           context: .
           push: true
           tags: user/app:latest
           cache-from: type=local,src=/tmp/.buildx-cache
           cache-to: type=local,dest=/tmp/.buildx-cache
3. Important Points: - 
docker/setup-buildx-action@v1
: This sets up Docker Buildx, which is necessary for the 
build-push-action
to leverage the 
cache-from
and 
cache-to
options. - 
actions/cache@v2
: This action is responsible for caching the Docker layers between builds. - 
docker/build-push-action@v2
: This action is used to build and push Docker images with the cache configuration set up. This setup assumes that you are using 
docker/build-push-action
to build and push your Docker images and that you want to cache the layers to speed up your builds. Adjust the cache key and paths as necessary for your specific setup. If you have further questions or need clarification on any parts, feel free to ask!
a
there's no prefect deployment in that step though
@Marvin Can you include a prefect deployment step as well? The docker build image is defined in the yaml file
m
To integrate a Prefect deployment step into your GitHub Actions workflow, you'll want to add a step that uses Prefect's CLI to deploy your flows. If your Docker image is defined in the 
prefect.yaml
file, you can incorporate both building the Docker image and deploying the Prefect flow in the same workflow. Here's how you might structure it:
Copy code
yaml
name: CI

on:
  push:
    branches:
      - main

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout code
      uses: actions/checkout@v2

    - name: Set up Docker Buildx
      uses: docker/setup-buildx-action@v1

    - name: Cache Docker layers
      uses: actions/cache@v2
      with:
        path: /tmp/.buildx-cache
        key: ${{ runner.os }}-buildx-${{ github.sha }}
        restore-keys: |
          ${{ runner.os }}-buildx-

    - name: Build Docker image
      uses: docker/build-push-action@v2
      with:
        context: .
        push: true  # Ensure this matches your needs, if not pushing to a registry, set to false
        tags: user/app:latest
        cache-from: type=local,src=/tmp/.buildx-cache
        cache-to: type=local,dest=/tmp/.buildx-cache
    
    - name: Install Prefect
      run: pip install prefect

    - name: Deploy Prefect Flow
      run: prefect deploy -f prefect.yaml
      env:
        PREFECT_API_URL: ${{ secrets.PREFECT_API_URL }}  # Ensure you have this secret set up
### Breakdown of New Steps: - Install Prefect: You'll need Prefect installed in your CI environment to run the deployment command. This can be done using a simple 
pip install prefect
. - Deploy Prefect Flow: This step runs 
prefect deploy -f prefect.yaml
to deploy your flow. Make sure the Prefect API URL is set correctly. It's securely stored as a GitHub secret, as environment variables should not contain sensitive information directly. ### Considerations - Ensure that the Prefect API URL and any other credentials Prefect might require are stored in GitHub Secrets to keep them secure. - Adjust the Docker tags and pushing strategy based on your needs. If you're pushing to a Docker registry, make sure you have the appropriate credentials set in your secrets. This setup should efficiently build your Docker image with caching and deploy your Prefect flow, all within a single GitHub Actions workflow. If you have more questions or need additional details, feel free to reach out!
a
Currently I'm building and pushing the docker image from inside 
prefect deploy -f prefect.yaml
. Can I keep it like that while having a cache? @Marvin
m
If you're building and pushing the Docker image as part of the Prefect deployment process specified in your 
prefect.yaml
, you can still leverage Docker layer caching in GitHub Actions. However, you'll need to set things up so that the cache is available during the Prefect deployment. Since the deployment and build are encapsulated within the Prefect CLI command, you'll focus on setting up the cache environment correctly before calling 
prefect deploy
. Here's how you can adjust your GitHub Actions workflow to include caching:
Copy code
yaml
name: CI

on:
  push:
    branches:
      - main

jobs:
  deploy:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout code
      uses: actions/checkout@v2

    - name: Set up Docker Buildx
      uses: docker/setup-buildx-action@v1

    - name: Cache Docker layers
      uses: actions/cache@v2
      with:
        path: /tmp/.buildx-cache
        key: ${{ runner.os }}-buildx-${{ github.sha }}
        restore-keys: |
          ${{ runner.os }}-buildx-

    - name: Install Prefect
      run: pip install prefect

    - name: Deploy Prefect Flow
      run: |
        # Ensure the cache directory exists
        mkdir -p /tmp/.buildx-cache
        
        # Run Prefect deploy with buildx cache options
        PREFECT_DOCKER_BUILDKIT=1 docker build \
          --cache-from=type=local,src=/tmp/.buildx-cache \
          --cache-to=type=local,dest=/tmp/.buildx-cache \
          -t your-image-name:latest .
        
        # Deploy using Prefect CLI
        prefect deploy -f prefect.yaml
      env:
        PREFECT_API_URL: ${{ secrets.PREFECT_API_URL }}

    - name: Push Docker Image
      run: docker push your-image-name:latest
      env:
        DOCKER_REGISTRY: your-registry-url  # Use this if needed
        DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
        DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
### Key Adjustments 1. Docker Build with Cache: - You manually run 
docker build
with cache options before deploying with Prefect, ensuring that your image layers are cached. - The 
PREFECT_DOCKER_BUILDKIT=1
environment variable is set to ensure BuildKit is used, which supports advanced features like caching. 2. Prefect CLI Deployment: - You still use the Prefect CLI to deploy your flow, letting it handle the task once the image has been built. 3. Authentication: Use secrets for sensitive information like Docker registry credentials to keep them secure. This setup allows you to take advantage of caching while keeping your current workflow of building within the Prefect deployment. Just be sure to replace placeholders like 
your-image-name
and 
your-registry-url
with your actual values. If you encounter any hiccups or have more questions, feel free to ask!
a
Can we do this step :
Copy code
# Run Prefect deploy with buildx cache options
        PREFECT_DOCKER_BUILDKIT=1 docker build \
          --cache-from=type=local,src=/tmp/.buildx-cache \
          --cache-to=type=local,dest=/tmp/.buildx-cache \
          -t your-image-name:latest .
with the prefect CLI? @Marvin
m
Incorporating Docker build caching directly within the Prefect CLI during the deployment process requires carefully setting up your Docker environment and possibly modifying your 
prefect.yaml
to accommodate caching. To use Docker build caching with Prefect's CLI when the deployment process involves building a Docker image, you must ensure your build environment is configured to utilize BuildKit and any cache settings are applied within the commands specified in your 
prefect.yaml
. Here’s a more coordinated approach: 1. Ensure BuildKit is enabled: Prefect should automatically use BuildKit if you're using it internally during the deployment process. 2. Modify the Docker build command within your 
prefect.yaml
to include caching flags if possible. This would typically be in the section where you specify the build process or commands for the Docker-based deployment. Unfortunately, the Prefect CLI currently doesn't natively provide an option to explicitly set Docker build cache parameters directly from CLI commands during the 
prefect deploy
. This means the caching configurations need to be integrated into the Docker commands or Dockerfile itself if Prefect is handling everything in a more automated way. Here's what you can do generally: - Dockerfile Adjustments: Ensure your Dockerfile is optimized for caching. Order operations from least to most frequently changed, and leverage multistage builds if your build process is complex. - Environment Preparation: If you're manually invoking 
docker build
within Prefect deployment hooks or scripts, you'll need to set up a similar cache structure through Docker itself. 3. Workflow Preparation: Make sure your Docker environment in GitHub Actions (or wherever you're deploying from) is set to use BuildKit. You'd typically set this up in the environment where the Docker daemon is running:
Copy code
bash
   export DOCKER_BUILDKIT=1
If Prefect changes or adds more features related to this, always check their latest documentation or GitHub issues for any nuanced updates regarding deployment enhancements. In this scenario, the best mimic of caching would be optimizing the Dockerfile for cache efficiency and setting up Docker environments correctly. If Prefect adds this capability directly in future updates, it'll likely get reflected in their CLI enhancements. Hope this helps, and feel free to let me know if there are more questions!
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