Developing IRIS applications with Docker and VSCode

It's essential to keep in mind, that ObjectScript code has to be compiled. And actually, there are two ways of doing this.

• Build stage, mostly with using Dockerfile
• Runtime stage, start vanilla IRIS and build application there.

Yes, docker build can be slow, but the issue here is that IRIS starts in fully functional mode, and it takes too much time to start. While it would be enough if IRIS would be started with very minimal functionality (no spare wrtitedaemons, no hot jobs for Interoperability, and so on)

Building an application in runtime does make not so much sense. First of all, it's not so simple to make this happen. And second, the logging of this is quite complicated as well. So, it makes the debugging of the build process much more difficult. And in the case of a significantly big project, it still will take a lot of time to be built, but with less understanding of the progress.

The ability to fail fast is quite important, and it's a sign to a developer, that something is odd. Building images with BuildKit, have a different way of logging, and it may not show the real reason for failure, but you can turn on the full logging this way

docker-compose build --progress plain

If your project uses ZPM, so, most probably you would have lines like this

RUN --mount=type=bind,src=.,dst=. \
  iris start iris && \
  iris session iris "##class(%ZPM.PackageManager).Shell(\"load /home/irisowner/$MODULE -v\",1,1)" && \
  ([ $TESTS -eq 0 ] || iris session iris "##class(%ZPM.PackageManager).Shell(\"test $MODULE -v -only\",1,1)") && \
  iris stop iris quietly

ZPM's Shell accepts three parameters

• executed command itself
• Fail on error
• Halt on exit

So, you can just change the second parameter (the first 1) to 0, and the build will be successful in any case

Could "docker commit" help out as an image snapshot that you can simply resume later. 

Would an image saved to tar or pushed to a repo make itteration portable also?

More simpler for a stopped container locally is to just start it again? Assuming the container is allowed to cache and not too much time has passed to allow the space to have been automatically reclaimed.