Reduce size of Docker image

[gvolpe]

Right now, the generated Docker image has 541 MBs of size, which is quite big.

Let's try to reduce it...

[calvinlfer]

Hey @gvolpe, I managed to set dockerBaseImage := "azul/zulu-openjdk-alpine:8" and enabling the AshScriptPlugin to allow for alpine based images reduces the size to 105 MB. However, the following key assignment causes an NPE (since I don't have these set in my shell):

    dockerEnvVars ++= Map(
      "SC_APP_ENV" -> System.getenv("SC_APP_ENV"),
      "SC_JWT_CLAIM" -> System.getenv("SC_JWT_CLAIM"),
      "SC_JWT_SECRET_KEY" -> System.getenv("SC_JWT_SECRET_KEY"),
      "SC_PASSWORD_SALT" -> System.getenv("SC_PASSWORD_SALT"),
      "SC_ACCESS_TOKEN_SECRET_KEY" -> System.getenv("SC_ACCESS_TOKEN_SECRET_KEY"),
      "SC_ADMIN_USER_TOKEN" -> System.getenv("SC_ADMIN_USER_TOKEN")
    ),

So I removed it and I was able to build and run the container.

Is there any reason why these are explicitly specified? as should just be able to feed in the environment variables via docker run or compose

[gvolpe]

No particular reason @calvinlfer , I actually need to come back to this once I start working on Chapter 9.

Last evening, there was another talk in the local Scala meetup (in Spanish) exactly about this, so I have some material :) https://slides.com/hugobellomusto/dockerizando-mi-scala-app#/