Refresh all repositories when performing an update of IU container

Currently the IUBundleContainer#update only queries the current P2
metadata that might be cached. This can lead to situations where when a
repository has "just changed" it does not see the latest metadata.

As we can assume that if the user mind to hit the update button it is
meant to really get the latest, this now ask the manager to update the
metadata (and possibly colocated artifacts) repository.

ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/target/IUBundleContainer.java

@@ -423,7 +423,7 @@ void synchronizerChanged(ITargetDefinition target) {
 	public synchronized IUBundleContainer update(Set<String> toUpdate, IProgressMonitor monitor) throws CoreException {
 		SubMonitor progress = SubMonitor.convert(monitor, 100);
 		IQueryable<IInstallableUnit> source = P2TargetUtils.getQueryableMetadata(fRepos, isFollowRepositoryReferences(),
-				progress.split(30));
+				true, progress.split(30));
 		boolean updated = false;
 		List<UnitDeclaration> updatedUnits = new ArrayList<>(fIUs);
 		SubMonitor loopProgress = progress.split(70).setWorkRemaining(updatedUnits.size());

ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/target/Messages.java

@@ -47,6 +47,8 @@ public class Messages extends NLS {
 	public static String LocalTargetHandle_3;
 	public static String LocalTargetHandle_4;
 	public static String LocalTargetHandle_5;
+	public static String P2TargetUtils_cant_refresh_artifacts;
+	public static String P2TargetUtils_cant_refresh_metadata;
 	public static String P2TargetUtils_ProvisioningSourceTask;
 	public static String ProfileBundleContainer_0;
 	public static String ProfileBundleContainer_2;

ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/target/Messages.properties

@@ -42,6 +42,8 @@ LocalTargetHandle_2=Unable to generate memento for target platform
 LocalTargetHandle_3=Failed to delete target definition: {0}
 LocalTargetHandle_4=Error saving target definition {0}
 LocalTargetHandle_5=Error creating target file
+P2TargetUtils_cant_refresh_artifacts=Can't refresh artifact repository {0}
+P2TargetUtils_cant_refresh_metadata=Can't refresh metadata repository {0} so the reported metadata might be outdated
 P2TargetUtils_ProvisioningSourceTask=Provisioning source bundles
 ProfileBundleContainer_0=Installation directory does not exist: {0}
 ProfileBundleContainer_2=Configuration directory does not exist: {0}

ui/org.eclipse.pde.core/src/org/eclipse/pde/internal/core/target/P2TargetUtils.java

@@ -92,6 +92,7 @@
 import org.eclipse.equinox.p2.repository.artifact.IFileArtifactRepository;
 import org.eclipse.equinox.p2.repository.metadata.IMetadataRepository;
 import org.eclipse.equinox.p2.repository.metadata.IMetadataRepositoryManager;
+import org.eclipse.osgi.util.NLS;
 import org.eclipse.pde.core.target.ITargetDefinition;
 import org.eclipse.pde.core.target.ITargetHandle;
 import org.eclipse.pde.core.target.ITargetLocation;
@@ -984,44 +985,108 @@ private static <T> T getP2Service(Class<T> key, String absentErrorMessage) throw
 	/**
 	 * Return a queryable on the metadata defined in the given repo locations
 	 *
-	 * @param repos the repos to lookup
-	 * @param followRepositoryReferences whether to follow repository references
-	 * @param monitor the progress monitor
+	 * @param repos
+	 *            the repos to lookup
+	 * @param followRepositoryReferences
+	 *            whether to follow repository references
+	 * @param monitor
+	 *            the progress monitor
 	 * @return the set of metadata repositories found
-	 * @throws CoreException if there is a problem getting the repositories
+	 * @throws CoreException
+	 *             if there is a problem getting the repositories
 	 */
 	static IQueryable<IInstallableUnit> getQueryableMetadata(Collection<URI> repos, boolean followRepositoryReferences,
 			IProgressMonitor monitor) throws CoreException {
-		IMetadataRepositoryManager manager = getRepoManager();
+		return getQueryableMetadata(repos, followRepositoryReferences, false, monitor);
+	}
+
+	/**
+	 * Return a queryable on the metadata defined in the given repo locations
+	 *
+	 * @param repos
+	 *            the repos to lookup
+	 * @param followRepositoryReferences
+	 *            whether to follow repository references
+	 * @param forceReload
+	 *            forces reloading of repositories
+	 * @param monitor
+	 *            the progress monitor
+	 * @return the set of metadata repositories found
+	 * @throws CoreException
+	 *             if there is a problem getting the repositories
+	 */
+	static IQueryable<IInstallableUnit> getQueryableMetadata(Collection<URI> repos, boolean followRepositoryReferences,
+			boolean forceReload,
+			IProgressMonitor monitor) throws CoreException {
+		IMetadataRepositoryManager metadataRepositoryManager = getRepoManager();
+		Collection<URI> existing = new LinkedHashSet<>(
+				Arrays.asList(metadataRepositoryManager.getKnownRepositories(IRepositoryManager.REPOSITORIES_ALL)));
 		if (repos.isEmpty()) {
-			repos = Arrays.asList(manager.getKnownRepositories(IRepositoryManager.REPOSITORIES_ALL));
+			repos = existing;
 		}
-		SubMonitor subMonitor = SubMonitor.convert(monitor, repos.size() * 2);
-
+		int work = repos.size() * (forceReload ? 4 : 2);
+		SubMonitor subMonitor = SubMonitor.convert(monitor, work);
 		Set<IRepositoryReference> seen = new HashSet<>();
 		List<IMetadataRepository> result = new ArrayList<>(repos.size());
 		List<IMetadataRepository> additional = new ArrayList<>();
 		MultiStatus repoStatus = new MultiStatus(PDECore.PLUGIN_ID, 0, Messages.IUBundleContainer_ProblemsLoadingRepositories);
 		for (URI location : repos) {
 			try {
-				IMetadataRepository repository = manager.loadRepository(location, subMonitor.split(1));
+				IMetadataRepository repository = metadataRepositoryManager.loadRepository(location, subMonitor.split(1));
 				result.add(repository);
 				if (followRepositoryReferences) {
-					addReferences(repository, additional, seen, manager, subMonitor.split(1));
+					addReferences(repository, additional, seen, metadataRepositoryManager, subMonitor.split(1));
 				}
 			} catch (ProvisionException e) {
 				repoStatus.add(e.getStatus());
 			}
 		}
-
 		if (result.size() != repos.size()) {
 			throw new CoreException(repoStatus);
 		}
 		result.addAll(additional);
-		if (result.size() == 1) {
-			return result.get(0);
+		if (result.isEmpty()) {
+			return QueryUtil.compoundQueryable(List.of());
+		}
+		Collection<IMetadataRepository> unique = new LinkedHashSet<>(result);
+		if (forceReload) {
+			List<IMetadataRepository> refreshed = new ArrayList<>();
+			subMonitor.setWorkRemaining(2 * unique.size());
+			IArtifactRepositoryManager artifactRepositoryManager = getArtifactRepositoryManager();
+			metadataRepositoryManager = getRepoManager();
+			Collection<URI> existingArtifactRepositories = new LinkedHashSet<>(
+					Arrays.asList(artifactRepositoryManager.getKnownRepositories(IRepositoryManager.REPOSITORIES_ALL)));
+			for (IMetadataRepository metadataRepository : unique) {
+				URI location = metadataRepository.getLocation();
+				if (existing.contains(location)) {
+					try {
+						refreshed.add(metadataRepositoryManager.refreshRepository(location, subMonitor.split(1)));
+					} catch (ProvisionException e) {
+						ILog.get().warn(NLS.bind(Messages.P2TargetUtils_cant_refresh_metadata, location), e);
+						// if refresh do not work, use the previously loaded
+						// repository
+						refreshed.add(metadataRepository);
+					}
+					if (existingArtifactRepositories.contains(location)) {
+						try {
+							artifactRepositoryManager.refreshRepository(location, subMonitor.split(1));
+						} catch (ProvisionException e) {
+							// we tried our best...
+							ILog.get().warn(NLS.bind(Messages.P2TargetUtils_cant_refresh_artifacts, location), e);
+						}
+					}
+				} else {
+					// the repo was just loaded as part of this call so it has
+					// to be (almost) fresh
+					refreshed.add(metadataRepository);
+				}
+			}
+			unique = refreshed;
+		}
+		if (unique.size() == 1) {
+			return unique.iterator().next();
 		}
-		return QueryUtil.compoundQueryable(new LinkedHashSet<>(result));
+		return QueryUtil.compoundQueryable(unique);
 	}
 
 	private static void addReferences(IMetadataRepository repository, List<IMetadataRepository> result,