public Dictionary <string, Relationship> CreateRelationships(object objectGraph, string parentId, IResourceMapping resourceMapping, Context context)
{
var relationships = new Dictionary <string, Relationship>();
foreach (var linkMapping in resourceMapping.Relationships)
{
var relationshipName = linkMapping.RelationshipName;
var rel = new Relationship();
var relLinks = new RelationshipLinks();
relLinks.Self = linkBuilder.RelationshipSelfLink(context, parentId, resourceMapping, linkMapping);
relLinks.Related = linkBuilder.RelationshipRelatedLink(context, parentId, resourceMapping, linkMapping);
if (!linkMapping.IsCollection)
{
string relatedId = null;
object relatedInstance = null;
if (linkMapping.RelatedResource != null)
{
relatedInstance = linkMapping.RelatedResource(objectGraph);
if (relatedInstance != null)
{
relatedId = linkMapping.ResourceMapping.IdGetter(relatedInstance).ToString();
}
}
if (linkMapping.RelatedResourceId != null && relatedId == null)
{
var id = linkMapping.RelatedResourceId(objectGraph);
if (id != null)
{
relatedId = id.ToString();
}
}
if (linkMapping.InclusionRule != ResourceInclusionRules.ForceOmit)
{
// Generating resource linkage for to-one relationships
if (relatedInstance != null)
{
rel.Data = new SingleResourceIdentifier
{
Id = relatedId,
Type = configuration.GetMapping(relatedInstance.GetType()).ResourceType // This allows polymorphic (subtyped) resources to be fully represented
}
}
;
else if (relatedId == null || linkMapping.InclusionRule == ResourceInclusionRules.ForceInclude)
{
rel.Data = new NullResourceIdentifier(); // two-state null case, see NullResourceIdentifier summary
}
}
}
else
{
IEnumerable relatedInstance = null;
if (linkMapping.RelatedResource != null)
{
relatedInstance = (IEnumerable)linkMapping.RelatedResource(objectGraph);
}
// Generating resource linkage for to-many relationships
if (linkMapping.InclusionRule == ResourceInclusionRules.ForceInclude && relatedInstance == null)
{
rel.Data = new MultipleResourceIdentifiers();
}
if (linkMapping.InclusionRule != ResourceInclusionRules.ForceOmit && relatedInstance != null)
{
var idGetter = linkMapping.ResourceMapping.IdGetter;
var identifiers = relatedInstance
.Cast <object>()
.Select(o => new SingleResourceIdentifier
{
Id = idGetter(o).ToString(),
Type = configuration.GetMapping(o.GetType()).ResourceType // This allows polymorphic (subtyped) resources to be fully represented
});
rel.Data = new MultipleResourceIdentifiers(identifiers);
}
// If data is present, count meta attribute is added for convenience
if (rel.Data != null)
{
rel.Meta = new Dictionary <string, string> {
{ MetaCountAttribute, ((MultipleResourceIdentifiers)rel.Data).Count.ToString() }
}
}
;
}
if (relLinks.Self != null || relLinks.Related != null)
{
rel.Links = relLinks;
}
if (rel.Data != null || rel.Links != null)
{
relationships.Add(relationshipName, rel);
}
}
return(relationships.Any() ? relationships : null);
}