As an extension developer, I would like to have the same dev mode experience as our users

[xstefank]

Description

I'm thinking about this for a while. Currently, when I develop an extension, I either need to restart my testing application (that uses the extension snapshot) or I do a hack like this:

export CURRENT=${C} && export C=$((C+1)) && sed -i 's#<dummy>'"${CURRENT}"'</dummy>#<dummy>'"${C}"'</dummy>#g' pom.xml

which triggers the restart of the maven process because pom.xml changed. But this is hacky and it still requires manual step.

I would like to have the restart of the testing app automatic, right when my extension "mvn install"s into my local repository.

Implementation ideas

This is why I'm opening this issue. There are several options.

Easiest would be to allow manual overriding of the "watchedFiles" on command line or/and in the maven plugin:

$ ./mvnw quarkus:dev -DwatchedFiles=~/.m2/repository/io/quarkus/quarkus-smallrye-health/999-SNAPSHOT/quarkus-smallrye-health-999-SNAPSHOT.jar

Or it can be just specifying the extension (snapshot) that should be reloaded:

$ ./mvnw quarkus:dev -DwatchedSnapshots=io.quarkus:quarkus-smallrye-health

Or we can specify it in the application.properties.

To me, the first option would give the most flexibility because there might other usecases beyong extension development that I don't see right now and we support kind of for the project files already but only in Java reload mode (not full maven process restart).

[xstefank]

Talked about this shortly with @aloubyansky this week already.

[aloubyansky]

I think the -DwatchedFiles approach could be the first step towards a proper support for this feature.

IMO, I wouldn't add this option to the application.properties. I think we may come up with more dev mode-related config options for extensions and other libraries that aren't found in the current workspace. Such as locations of those dependency code repositories a user is working on. This kind of config would be specific to a dev environment. I'd consider .quarkus/dev.yaml or .quarkus/config.yaml (we'd need to be careful with other config in it) for this purpose.

[aloubyansky]

By a proper support I mean not requiring mvn install for dependencies to be reloaded. If we are thinking of "the same dev mode experience", I'd expect just code changes in non-reloadable dependencies in the current or an external code repository to trigger a restart.