Here are the steps to use Docker with Travis CI:
Travis CI is a free platform for continuous integration that supports Docker. You can automate the building and deployment of your Docker images using Travis CI. Here’s how.
1. You should have a Dockerfile ready in your project repository. This Dockerfile is a text file that contains all the commands you would normally execute in your command line to build a Docker image.
1. Create a .travis.yml file in your root directory. Travis CI uses this file to understand how to build your project.
1. Enable Travis CI for your repository. You can do this by going to your Travis CI profile, and flicking the repository switch on.
1. For Docker, include the services keyword in your .travis.yml file:
```
sudo: required
services:
– docker
```
1. Now you can build your Docker image. Let’s say your Dockerfile is in the root directory and you want to tag your image with the name my-image. You can do this in the `before_install` section:
```
before_install:
– docker build -t my-image .
```
1. Then, to run your containers, include them as part of your script:
```
script:
– docker run my-image
```
1. You can also login to Docker in your .travis.yml file. This is useful if you want to push your image to Docker Hub:
```
before_script:
- echo “$DOCKER_PASSWORD” | docker login -u “$DOCKER_USERNAME” —password-stdin
```
Set the `DOCKER_USERNAME` and `DOCKER_PASSWORD` in your Travis CI repository settings.
1. Then you can push your built image to Docker Hub in the `after_success` block:
```
after_success:
– docker push my-image
```
1. Commit your .travis.yml file and push to your Git repository. Travis CI will automatically build and test your application.
The following is an example of .travis.yml file using Docker:
```
sudo: required
services: – docker
before_install: – docker build -t my-image .
before_script:
- echo “$DOCKER_PASSWORD” | docker login -u “$DOCKER_USERNAME” —password-stdin
script:
– docker run my-image
after_success:
– docker push my-image
```
1. This script will build your Docker image, run any commands you have specified, and then, if successful, push your newly built image to Docker Hub.
Remember to replace `my-image` and `
