ohif-viewer/Packages/ohif-core/client/lib/retrieveStudyMetadata.js

62 lines
2.4 KiB
JavaScript

import { Meteor } from 'meteor/meteor';
import { OHIF } from 'meteor/ohif:core';
// Define the StudyMetaDataPromises object. This is used as a cache to store study meta data
// promises and prevent unnecessary subsequent calls to the server
const StudyMetaDataPromises = new Map();
/**
* 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
*
*/
OHIF.studies.deleteStudyMetadataPromise = (studyInstanceUid) => {
if (StudyMetaDataPromises.has(studyInstanceUid)) {
StudyMetaDataPromises.delete(studyInstanceUid);
}
};
/**
* Retrieves study metadata using a server call
*
* @param {String} studyInstanceUid The UID of the Study to be retrieved
* @returns {Promise} that will be resolved with the metadata or rejected with the error
*/
OHIF.studies.retrieveStudyMetadata = (studyInstanceUid, seriesInstanceUids) => {
// @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 the StudyMetaDataPromises cache already has a pending or resolved promise related to the
// given studyInstanceUid, then that promise is returned
if (StudyMetaDataPromises.has(studyInstanceUid)) {
return StudyMetaDataPromises.get(studyInstanceUid);
}
const seriesKeys = Array.isArray(seriesInstanceUids) ? '|' + seriesInstanceUids.join('|') : '';
const timingKey = `retrieveStudyMetadata[${studyInstanceUid}${seriesKeys}]`;
OHIF.log.time(timingKey);
// Create a promise to handle the data retrieval
const promise = new Promise((resolve, reject) => {
const server = OHIF.servers.getCurrentServer();
// If no study metadata is in the cache variable, we need to retrieve it from
// the server with a call.
if (server.type === 'dicomWeb' && server.requestOptions.requestFromBrowser === true) {
OHIF.studies.services.WADO.RetrieveMetadata(server, studyInstanceUid).then(function (data) {
resolve(data)
}, reject);
}
});
// Store the promise in cache
StudyMetaDataPromises.set(studyInstanceUid, promise);
return promise;
};