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Command line to find units in a p2 repository using p2 query language


p2 has a query language that allows to run queries on the content of a p2 repository. However all examples in the documentation assume that the query language is used from within Java, e.g.

IQuery<IInstallableUnit> q = QueryUtil.createMatchQuery("this.id == $0", id);
metadataRepository.query(q);

How can I execute a query from the command line (without writing my own Java application)?


Solution

  • The p2 director application has an option to list or query the content of the given p2 repositories. With -list you'd get all units, and with -list Q:<p2 QL collection query> you can query for a subset.

    The expression needs to be a collection query, so instead of the match query in the example given above, you need to use the equivalent collection query. Also, placeholders like $1 must be replaced by the actual values.

    Example: The command line to look for the all org.eclipse.sdk.ide units in the Juno release train repository would be

    eclipse -application org.eclipse.equinox.p2.director \
       -repository http://download.eclipse.org/releases/juno \
       -list 'Q:everything.select(x | x.id == "org.eclipse.sdk.ide")'
    

    As a more useful example, you could use this command to find all units which are shown in categories in the p2 user interface (although I wouldn't try a large repository, the query seems to be quite slow):

    eclipse -application org.eclipse.equinox.p2.director \
       -repository <URL of some small repository> \
       -list 'Q:everything.select(y | everything.select(x | x.properties ~= filter("(org.eclipse.equinox.p2.type.category=true)")).collect(x | x.requirements).flatten().exists(r | y ~= r))'