How do I use Docker executors in CircleCI?

How do I use Docker executors in CircleCI?

To use Docker executors in CircleCI, you need to define the executor in your config.yml file. Here's a basic example:

version: 2.1
executors:
  docker-executor:
    docker:
      - image: circleci/python:3.8
jobs:
  build:
    executor: docker-executor
    steps:
      - checkout
      - run: python -m unittest discover

What are the benefits of using Docker executors?

Docker executors provide a consistent environment for your builds, allowing you to easily manage dependencies and isolate your applications. They also enable faster builds by leveraging Docker's caching capabilities.

Can I use multiple Docker images in a single job?

Yes, you can use multiple Docker images in a single job by defining additional services in your config.yml. For example:

jobs:
  build:
    executor: docker-executor
    steps:
      - checkout
      - run: echo 'Running with multiple services'
    services:
      - docker:
          image: circleci/mysql:5.7

How do I debug issues with Docker executors?

To debug issues with Docker executors, you can use the run step to execute commands and print logs. Additionally, CircleCI provides a built-in SSH feature that allows you to access the build environment for troubleshooting.