Configuring your pipeline to build new Docker images

Docker can build new images by reading instructions from a Dockerfile. Prepare a Dockerfile to take a base Docker image and add code from your customization package to create a new Docker image.

Before you begin

Ensure that Docker is installed.
Build the customization package that includes the custom assets.

Procedure

Create a script that can be used by your pipeline to complete the following steps.

Pull the latest customized package from the artifact repository and extract the package to a folder called CusDeploy.
Create a Dockerfile on the same level as the CusDeploy folder.
Add the following text to the Dockerfile and update with your values.
```
FROM  docker_url/library/source_image_name:source_image_tag
COPY CusDeploy /SETUP/Cus
RUN /SETUP/bin/applyCustomization.sh
<other_RunEngine_commands>
```
docker_url

The Docker repository hostname where to get the source image.

library

The path to your source image in the repository.

source_image_name

The name of the source image. For example, ts-app, ts-web, crs-app, search-app, xc-app.

source_image_tag

The tag of the source image that you want to use.

other_RunEngine_commands

(Optional) You can specify commands to configure the application inside the Docker image. For example, you can add commands to set the data source so that the application can connect to your database. For more information about Run Engine commands, see Run Engine commands.
- The FROM argument specifies which base Docker image to update.
- The RUN argument references a shell script that instructs Docker how to apply the customization package to the base image.
For example,
```
FROM  myDockerRegisty.com/commerce/ts-app:latest
COPY CusDeploy /SETUP/Cus
RUN /SETUP/bin/applyCustomization.sh
```
Build the new Docker image.
For example, run the following command.
```
docker build -t <target_image_name>:<tag>
```
You most likely want to keep the <target_image_name> the same as the source_image_name. Depending how you want to maintain your Docker images in the repository, you might want to also use the same tag, or specify a unique tag such as the timestamp of the build.
Repeat steps 2 to 4 for the other Docker images that you need to update.
Push the new Docker images to your Docker repository.

What to do next

Deploy the new Docker images by using the pipeline that you created in Configuring your pipeline to deploy Docker images.