Colectica SDK: Find all referencing items. Group different versions of the same item together.

gistfile1.cs

/// <summary>
/// Gets a list of items that reference the item specified by id.
/// This list may contain multiple entries for an individual item if 
/// multiple versions of that item reference the base item.
/// We will group these "duplicates" and print each item only once,
/// with a list of matching versions if appropriate.
/// </summary>
/// <param name="id"></param>
public static void PrintReferencingItemInfo(RepositoryClientBase client, IdentifierTriple targetId)
{
	SetSearchFacet facet = new SetSearchFacet();
	facet.ReverseTraversal = true;
	facet.Predicate = RelationshipPredicates.ResourceReference;

	// Ask the server for a list of IDs that match our search terms.
	Collection<TypedIdTriple> typedIDs = client.SearchTypedSet(targetId, facet);
	var allIDs = typedIDs.ToIdentifierCollection();

	// Grab descriptions for each item returned.
	var descriptions = client.GetRepositoryItemDescriptions(allIDs).OrderBy(x => x.ItemType);

	// Group items by their unique identifier.
	// Technically this should group by Agency + Identifier, not just Identifier.
	// But since our identifiers are globally unique, this is no big deal.
	var grouped = descriptions.GroupBy(x => x.Identifier);

	Collection<IdentifierTriple> ids = new Collection<IdentifierTriple>();
	foreach (var descriptionGroup in grouped)
	{
		var desc = descriptionGroup.FirstOrDefault();
		if (desc == null) continue;

		string text = desc.DisplayLabel;
		if (string.IsNullOrWhiteSpace(text))
		{
			text = "Unnamed item";
		}
		Console.Write(text);
		Console.Write(": ");

		var allVersions = descriptionGroup.Select(d => d.Version);
		var versionStr = string.Join(",", allVersions);
		Console.WriteLine(versionStr);
	}
}