Developing an Apama application using the Docker image
The Dockerfile that you created in
Deploying an Apama application in Docker fixes or bakes in the
app directory and its contents. Thus, you would have to recreate the image every time the configuration file or the EPL files change, which is inconvenient during the development phase of the application where the EPL changes frequently. You can address that by mapping in a local directory when running the container and use that to hold your application. For example:
docker run -d --rm --name container -v /local/path:/app \
softwareag/apama-correlator:version correlator --config /app
Note:
The above command is broken over two lines via the \ escape character at the end of line. You can either copy this line verbatim or construct it to be a single line command.
Keep in mind that you are using the official image and not creating your own. Because you are mounting in a local directory containing the application, there is no need to build a custom image. It will be read from the /local/path which is mounted in instead.
Now you can make changes to the EPL or init.yaml file and simply restart the container to pick up the changes. When you have completed your changes and want to deploy, you can add a Dockerfile to bake the files into the image again. It is possible to define and map multiple volumes, allowing flexible usage of the image.