[tycho-user] Can a p2 repository be setup during the Maven build or must

[Craig Reichenbach <craigeebach@xxxxxxxxx>]

Hello,

Is it possible to setup a p2 repository on the fly during 
the Maven build?  It appears there is not and that the p2 repository 
must be in place before running Maven, which validates p2 repositories 
immediately after starting.  So the build fails immediately if a p2 
repository type is specified in any pom.xml in your project that does 
not actually exist yet.  Can anyone else confirm?   This is obviously 
quite different from the way Maven handles dependencies at build time.  
More details, and my workaround below. 

-Craig

My situation is as follows:

Build A produces an eclipse p2 repository and is deploying it to Nexus as a zip artifact.
Build B is using Tycho to build a set of eclipse plugins that depend on build A's eclipse p2 repository.


We are using Nexus OSS (not Pro).

What is the best way to have build B consume the p2 repository created by build A?  

My
 solution at this point is to create a Maven "fetcher" project ("pom" 
packaging type) in build B that unpacks the p2 repository zip artifact 
from Nexus to a local location using the maven-dependency-plugin's 
unpack goal.  I had expected to be able to execute this project as part 
of build B before the eclipse projects were built.  However, build B 
fails immediately after starting because the first thing that happens, 
before any project is built, is that the target platforms are evaluated 
for all Tycho eclipse projects.  In this case the local p2 repository I 
have defined in one of my pom.xml files does not exist yet since my 
fetcher project did not yet download & unpack it.  

To overcome this, I run Maven to build only the fetcher project as 
part of a prebuild step.  Once this completes, Maven is run a second 
time for the overall build which now works fine since the local 
repository has been established beforehand.

I would have expected to have had the opportunity to setup my p2 
repository as part of a Maven build, but Tycho appears to expect the p2 
repository to be in place before the build starts.  This is fine for 
repos that are static, like eclipse helios or indigo repositories, but 
is not good for repos that are built in a continuously integrated 
manner, and shared through a Maven repo like Nexus OSS.  I wonder of 
Nexus Pro addresses this by posting p2 repositories in a way that is 
remotely consumable by other Maven builds?