Parties

A party is the person or organization a record belongs to: the owner of an asset, the customer of a work order. The same word "customer" has meant a user id in one module and a Customers record id in another, so records name parties with a kind and an id instead.

The contracts are in CrestApps.OrchardCore.Parties.Abstractions. There is no feature; the modules that keep parties register sources.

PartyRef

PartyRef { Kind, Id } is a value type. Kind is an open string; PartyKinds names the well-known ones:

Kind	The id is	Source	Registered by
User	An Orchard Core user id	UserPartySource (IUserSearchService, named by IDisplayNameProvider)	The CrestApps Users module, and Assets when OrchardCore.Users is on
Customer	A Customers module customer record id	CustomerPartySource	Customers
Account	An account content item id	AccountPartySource	Accounts
Contact	A CRM contact content item id	Assets' contact source	Assets, when Omnichannel Management is on
Guest	A guest's id	none yet

PartyRef.ToString() writes Kind:Id, and PartyRef.TryParse reads it back.

Finding and naming parties

Inject IPartyDirectory (register it with services.AddPartyDirectory()):

• Kinds lists the kinds that have a source, and GetSource(kind) returns it (kinds compare without case; the first source registered for a kind answers).
• SearchAsync(kind, query, count) finds parties of a kind for a picker; each result is a PartyOption { Id, Name }.
• GetNameAsync(party) and GetNamesAsync(parties) name parties, with one lookup per kind.

Adding a kind of party

Implement IPartySource (Kind, SearchAsync, GetNamesAsync) in the module that keeps the records, or its .Core project, and register it:

services.AddPartySource<VendorPartySource>();

Consumers

• Assets reads an asset's owner through the party sources. The stored AssetOwnerKind keeps its values: Customer holds a user id and maps to the User party kind (AssetOwners.ToPartyKind, asset.ToParty()).
• Work Orders picks and names a work order's customer, account and contact through IPartyDirectory. WorkOrder.CustomerId and ServiceAgreement.CustomerId keep their stored name and hold a user id (party kind User).