WIP build up displaysets.

extensions/default/src/DicomWebDataSource/retrieveStudyMetadata.js

@@ -0,0 +1,71 @@
+import RetrieveMetadata from './services/wado/retrieveMetadata.js';
+
+const moduleName = 'RetrieveStudyMetadata';
+// Cache for promises. Prevents unnecessary subsequent calls to the server
+const StudyMetaDataPromises = new Map();
+
+/**
+ * Retrieves study metadata
+ *
+ * @param {Object} server Object with server configuration parameters
+ * @param {string} StudyInstanceUID The UID of the Study to be retrieved
+ * @param {Object} [filters] - Object containing filters to be applied on retrieve metadata process
+ * @param {string} [filter.seriesInstanceUID] - series instance uid to filter results against
+ * @returns {Promise} that will be resolved with the metadata or rejected with the error
+ */
+export function retrieveStudyMetadata(
+  dicomWebClient,
+  StudyInstanceUID,
+  enableStudyLazyLoad,
+  filters
+) {
+  // @TODO: Whenever a study metadata request has failed, its related promise will be rejected once and for all
+  // and further requests for that metadata will always fail. On failure, we probably need to remove the
+  // corresponding promise from the "StudyMetaDataPromises" map...
+
+  if (!dicomWebClient) {
+    throw new Error(
+      `${moduleName}: Required 'dicomWebClient' parameter not provided.`
+    );
+  }
+  if (!StudyInstanceUID) {
+    throw new Error(
+      `${moduleName}: Required 'StudyInstanceUID' parameter not provided.`
+    );
+  }
+
+  // Already waiting on result? Return cached promise
+  if (StudyMetaDataPromises.has(StudyInstanceUID)) {
+    return StudyMetaDataPromises.get(StudyInstanceUID);
+  }
+
+  // Create a promise to handle the data retrieval
+  const promise = new Promise((resolve, reject) => {
+    RetrieveMetadata(
+      dicomWebClient,
+      StudyInstanceUID,
+      enableStudyLazyLoad,
+      filters
+    ).then(function(data) {
+      resolve(data);
+    }, reject);
+  });
+
+  // Store the promise in cache
+  StudyMetaDataPromises.set(StudyInstanceUID, promise);
+
+  return promise;
+}
+
+/**
+ * Delete the cached study metadata retrieval promise to ensure that the browser will
+ * re-retrieve the study metadata when it is next requested
+ *
+ * @param {String} StudyInstanceUID The UID of the Study to be removed from cache
+ *
+ */
+export function deleteStudyMetadataPromise(StudyInstanceUID) {
+  if (StudyMetaDataPromises.has(StudyInstanceUID)) {
+    StudyMetaDataPromises.delete(StudyInstanceUID);
+  }
+}