Generalize ItemGraph, consistently query the same graph (#501 #163)

frontend/src/common-adapters/item-graph.ts

@@ -1,11 +1,11 @@
-import { extend } from 'lodash';
+import { extend, result, isString } from 'lodash';
 
 import { item } from '../common-rdf/ns';
 import Node from '../common-rdf/node';
 import Graph from '../common-rdf/graph';
 import { asURI } from '../utilities/linked-data-utilities';
 
-import { sparqlRoot } from 'config.json';
+import { nsRoot, sparqlRoot } from 'config.json';
 
 /**
  * Using query parameters is DEPRECATED in favor of SPARQL queries.
@@ -84,9 +84,36 @@ function isLiteralQuery(params: QueryParams): params is QueryParamsLiteral {
  * See also the query and sparqlQuery methods below for querying the server.
  */
 export default class ItemGraph extends Graph {
+    sparqlEndpoint: string;
+
     // Only defined if a query has been issued.
     promise: JQuery.jqXHR;
 
+    /**
+     * We allow client code to override `this.url` through the `graph` option.
+       For convenience, it is also possible to pass just the graph URL directly
+       as the only argument.
+     *
+     * From `this.url`, we derive the matching `this.sparqlEndpoint`.
+     */
+    constructor(graph: string);
+    constructor(models?: Node[] | Object[], options?: any);
+    constructor(models?: Node[] | Object[] | string, options?) {
+        if (isString(models)) {
+            options = { graph: models };
+            models = null;
+        }
+        super(models, options);
+    }
+
+    preinitialize(models?, options?: any): void {
+        super.preinitialize(models, options);
+        if (options.graph) this.url = options.graph;
+        const url = result(this, 'url') as string;
+        const graphName = url.slice(nsRoot.length, -1);
+        this.sparqlEndpoint = `${sparqlRoot}${graphName}/query`;
+    }
+
     /**
      * DEPRECATED you still need this for the download parameter, but use
      * sparqlQuery instead if you don't use that parameter.
@@ -113,8 +140,8 @@ export default class ItemGraph extends Graph {
      * result from the given CONSTRUCT query. For best results, make sure that
      * the query produces complete items.
      */
-    sparqlQuery(query: string, fromGraph: string): JQuery.jqXHR {
-        return this.promise = this.fetch({ url: sparqlRoot + fromGraph, data: $.param({ query: query }), remove: false });
+    sparqlQuery(query: string): JQuery.jqXHR {
+        return this.promise = this.fetch({ url: this.sparqlEndpoint, data: $.param({ query: query }), remove: false });
     }
 
     /**

frontend/src/explorer/explorer-event-controller.ts

@@ -92,7 +92,7 @@ class ExplorerEventController {
         const items = new ItemGraph();
         model.when(
             'query',
-            (model, query) => items.sparqlQuery(modelToQuery(query), 'item/query')
+            (model, query) => items.sparqlQuery(modelToQuery(query)),
         );
         if (model.isNew()) model.save();
         const collection = new FlatItemCollection(items);
@@ -339,7 +339,7 @@ export default ExplorerEventController;
 export function getItems(source: Node): ItemGraph {
     const sparqlItems = new ItemGraph();
     let queryString = itemsForSourceQuery(asURI(source), {});
-    sparqlItems.sparqlQuery(queryString, 'item/query');
+    sparqlItems.sparqlQuery(queryString);
     return sparqlItems;
 }
 

frontend/src/global/source-list.ts

@@ -1,13 +1,14 @@
+import Collection from '../core/collection';
 import ItemGraph from '../common-adapters/item-graph';
 import ldChannel from '../common-rdf/radio';
-import Collection from '../core/collection';
+import { source } from '../common-rdf/ns';
 import { parseResponse, nodeListFactory, userNodesFactory } from '../utilities/prefetch-utilities';
 
 const sourceList = new Collection();
 sourceList.parse = parseResponse;
 const getNodeList = nodeListFactory();
 
-const userSources = new ItemGraph();
+const userSources = new ItemGraph(source());
 const getUserNodes = userNodesFactory();
 
 /**

frontend/src/panel-browse/browse-view.ts

@@ -7,6 +7,7 @@ import { CompositeView } from "../core/view";
 import { randomNodesQuery } from "../sparql/compile-query";
 import explorerChannel from '../explorer/explorer-radio';
 import ldChannel from '../common-rdf/radio';
+import { item, source } from '../common-rdf/ns';
 
 import Collection from '../core/collection';
 import FlatItem from '../common-adapters/flat-item-model';
@@ -36,9 +37,9 @@ export default class BrowseView extends CompositeView {
     queryingItems: boolean;
 
     async initialize(options: ViewOptions) {
-        this.sparqlItems = new ItemGraph();
-        this.queryingItems = options.queryMode === 'items'? true : false;
-        this.endpoint =  this.queryingItems? 'item/query' : 'source/query';
+        this.queryingItems = options.queryMode === 'items';
+        const graphName = this.queryingItems? item() : source();
+        this.sparqlItems = new ItemGraph(graphName);
         if (options.landing) {
             this.title = "My " + options.queryMode;
             await this.getUserNodes();
@@ -64,7 +65,7 @@ export default class BrowseView extends CompositeView {
     async getRandomNodes(nodes: Collection) {
         const randomNodes = sampleSize(nodes.models, nSamples);
         const randomQuery = randomNodesQuery(randomNodes.slice(-randomNodes.length, -1), randomNodes.pop(), {});
-        this.sparqlItems.sparqlQuery(randomQuery, this.endpoint);
+        this.sparqlItems.sparqlQuery(randomQuery);
     }
 
     async getUserNodes() {

frontend/src/semantic-search/filter-input-view.ts

@@ -40,7 +40,7 @@ export default class FilterInput extends CompositeView {
             const rangeId = range.first().id;
             if (!rangeId.startsWith(xsd())) {
                 items = new ItemGraph();
-                items.sparqlQuery(filterInputQueryTemplate({ type: rangeId }), 'item/query');
+                items.sparqlQuery(filterInputQueryTemplate({ type: rangeId }));
                 this.subviews.push(new Select2Picker({ collection: items }));
             }
         }

frontend/src/utilities/prefetch-utilities.ts

@@ -14,12 +14,11 @@ export function userNodesFactory() {
 
     function getUserNodes(userNodes: ItemGraph, queryingItems: boolean): PromiseLike<ItemGraph> {
         if (!promise) {
-            const endpoint = queryingItems ? 'item/query' : 'source/query';
             promise = nodesByUserQuery(queryingItems, {}).then( (query) => {
                 if (!query) {
                     return handleError('user not authenticated');
                 }
-                return userNodes.sparqlQuery(query, endpoint).then(
+                return userNodes.sparqlQuery(query).then(
                     () => handleSuccess(userNodes), handleError
                 );
             });