@ -14,6 +14,33 @@ import { v4 } from "uuid";
import type { nodeEventListener } from "@ldo/subscribable-dataset" ;
import type { Quad } from "@rdfjs/types" ;
/ * *
* Represents a query over multiple datasources and constituting muliple
* resources .
*
* @example
* ` ` ` typescript
* import { ProfileShapeType } from "./.ldo/Profile.shapeType.ts" ;
*
* // Create a link query
* const linkQuery = ldoDataset
* . usingType ( ProfileShapeType )
* . startLinkQuery (
* "http://example.com/profile/card" ,
* "http://example.com/profile/card#me" ,
* {
* name : true ,
* knows : {
* name : true ,
* } ,
* } ,
* }
* ) ;
* // Susbscribe to this link query, automaticically updating the dataset when
* // something from the link query is changed.
* await linkQuery . subscribe ( ) ;
* ` ` `
* /
export class ResourceLinkQuery <
Type extends LdoBase ,
QueryInput extends LQInput < Type > ,
@ -34,6 +61,15 @@ export class ResourceLinkQuery<
Promise < void > | undefined
> = { } ;
/ * *
* @internal
* @param parentDataset The dataset for which this link query is a part
* @param shapeType A ShapeType for the link query to follow
* @param ldoBuilder An LdoBuilder associated with the dataset
* @param startingResource The resource to explore first in the link query
* @param startingSubject The starting point of the link query
* @param linkQueryInput A definition of the link query
* /
constructor (
protected parentDataset : IConnectedLdoDataset < Plugins > ,
protected shapeType : ShapeType < Type > ,
@ -43,6 +79,39 @@ export class ResourceLinkQuery<
protected linkQueryInput : QueryInput ,
) { }
/ * *
* Runs this link query , returning the result
* @param options Options for how to run the link query
* @returns A subset of the ShapeType as defined by the LinkQuery
*
* @example
* ` ` `
* import { ProfileShapeType } from "./.ldo/Profile.shapeType.ts" ;
*
* // Create a link query
* const linkQuery = ldoDataset
* . usingType ( ProfileShapeType )
* . startLinkQuery (
* "http://example.com/profile/card" ,
* "http://example.com/profile/card#me" ,
* {
* name : true ,
* knows : {
* name : true ,
* } ,
* } ,
* }
* ) ;
* // Susbscribe to this link query, automaticically updating the dataset when
* // something from the link query is changed.
* const result = await linkQuery . read ( ) ;
* console . log ( result . name ) ;
* result . knows . forEach ( ( person ) = > console . log ( person . name ) ) ;
* // The following will type-error. Despite "phone" existing on a Profile,
* // it was not covered by the link query.
* console . log ( result . phone ) ;
* ` ` `
* /
async run ( options ? : {
reload? : boolean ;
} ) : Promise < ExpandDeep < LQReturn < Type , QueryInput > >> {
@ -57,6 +126,42 @@ export class ResourceLinkQuery<
return this . fromSubject ( ) ;
}
/ * *
* Subscribes to the data defined by the link query , updating the dataset if
* any changes are made .
* @returns An unsubscribeId
*
* @example
* ` ` `
* import { ProfileShapeType } from "./.ldo/Profile.shapeType.ts" ;
*
* // Create a link query
* const linkQuery = ldoDataset
* . usingType ( ProfileShapeType )
* . startLinkQuery (
* "http://example.com/profile/card" ,
* "http://example.com/profile/card#me" ,
* {
* name : true ,
* knows : {
* name : true ,
* } ,
* } ,
* }
* ) ;
* // Susbscribe to this link query, automaticically updating the dataset when
* // something from the link query is changed.
* const unsubscribeId = await linkQuery . subscribe ( ) ;
*
* // Now, let's imagine the following triple was added to
* "http://example.com/profile/card" :
* < http : / / example.com / profile / card # me > < http : / / xmlns.com / foaf / 0.1 / knows > < http : / / example2.com / profile / card # me >
* Because you ' re subscribed , the dataset will automatically be updated .
*
* // End subscription
* linkQuery . unsubscribe ( unsubscribeId ) ;
* ` ` `
* /
async subscribe ( ) : Promise < string > {
const subscriptionId = v4 ( ) ;
this . thisUnsubscribeIds . add ( subscriptionId ) ;
Jackson Morgan
4 months ago