@cleerlycode/cornerstone-wado-image-loader

<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>imageLoader/wadouri/dataSetCacheManager.js - Documentation</title> <script src="scripts/prettify/prettify.js"></script> <script src="scripts/prettify/lang-css.js"></script>  <link type="text/css" rel="stylesheet" href="styles/prettify.css"> <link type="text/css" rel="stylesheet" href="styles/jsdoc.css"> </head> <body> <input type="checkbox" id="nav-trigger" class="nav-trigger" /> <label for="nav-trigger" class="navicon-button x"> <div class="navicon"></div> </label> <label for="nav-trigger" class="overlay"></label> <nav> <h2><a href="index.html">Home</a></h2><h3>Global</h3><ul><li><a href="global.html#addTask">addTask</a></li><li><a href="global.html#arrayBufferToString">arrayBufferToString</a></li><li><a href="global.html#cacheSizeInBytes">cacheSizeInBytes</a></li><li><a href="global.html#cancelTask">cancelTask</a></li><li><a href="global.html#framesAreFragmented">framesAreFragmented</a></li><li><a href="global.html#getNumberString">getNumberString</a></li><li><a href="global.html#getNumberValues">getNumberValues</a></li><li><a href="global.html#getStatistics">getStatistics</a></li><li><a href="global.html#getTransferSyntaxForContentType">getTransferSyntaxForContentType</a></li><li><a href="global.html#getUncompressedImageFrame">getUncompressedImageFrame</a></li><li><a href="global.html#getValue">getValue</a></li><li><a href="global.html#handleMessageFromWorker">handleMessageFromWorker</a></li><li><a href="global.html#handler">handler</a></li><li><a href="global.html#initialize">initialize</a></li><li><a href="global.html#loadCodecs">loadCodecs</a></li><li><a href="global.html#loadWebWorkerTask">loadWebWorkerTask</a></li><li><a href="global.html#registerLoaders">registerLoaders</a></li><li><a href="global.html#registerTaskHandler">registerTaskHandler</a></li><li><a href="global.html#setPixelDataType">setPixelDataType</a></li><li><a href="global.html#setTaskPriority">setTaskPriority</a></li><li><a href="global.html#spawnWebWorker">spawnWebWorker</a></li><li><a href="global.html#startTaskOnWebWorker">startTaskOnWebWorker</a></li><li><a href="global.html#unpackBinaryFrame">unpackBinaryFrame</a></li></ul> </nav> <div id="main"> <h1 class="page-title">imageLoader/wadouri/dataSetCacheManager.js</h1> <section> <article> <pre class="prettyprint source linenums"><code>import { dicomParser, external } from '../../externalModules.js'; import { xhrRequest } from '../internal/index.js'; /** * This object supports loading of DICOM P10 dataset from a uri and caching it so it can be accessed * by the caller. This allows a caller to access the datasets without having to go through cornerstone's * image loader mechanism. One reason a caller may need to do this is to determine the number of frames * in a multiframe sop instance so it can create the imageId's correctly. */ let cacheSizeInBytes = 0; let loadedDataSets = {}; let promises = {}; // returns true if the wadouri for the specified index has been loaded function isLoaded (uri) { return loadedDataSets[uri] !== undefined; } function get (uri) { if (!loadedDataSets[uri]) { return; } return loadedDataSets[uri].dataSet; } // loads the dicom dataset from the wadouri sp function load (uri, loadRequest = xhrRequest, imageId) { const cornerstone = external.cornerstone; // if already loaded return it right away if (loadedDataSets[uri]) { // console.log('using loaded dataset ' + uri); return new Promise((resolve) => { loadedDataSets[uri].cacheCount++; resolve(loadedDataSets[uri].dataSet); }); } // if we are currently loading this uri, increment the cacheCount and return its promise if (promises[uri]) { // console.log('returning existing load promise for ' + uri); promises[uri].cacheCount++; return promises[uri]; } // This uri is not loaded or being loaded, load it via an xhrRequest const loadDICOMPromise = loadRequest(uri, imageId); // handle success and failure of the XHR request load const promise = new Promise((resolve, reject) => { loadDICOMPromise.then(function (dicomPart10AsArrayBuffer/* , xhr*/) { const byteArray = new Uint8Array(dicomPart10AsArrayBuffer); // Reject the promise if parsing the dicom file fails let dataSet; try { dataSet = dicomParser.parseDicom(byteArray); } catch (error) { return reject(error); } loadedDataSets[uri] = { dataSet, cacheCount: promise.cacheCount }; cacheSizeInBytes += dataSet.byteArray.length; resolve(dataSet); cornerstone.triggerEvent(cornerstone.events, 'datasetscachechanged', { uri, action: 'loaded', cacheInfo: getInfo() }); }, reject).then(() => { // Remove the promise if success delete promises[uri]; }, () => { // Remove the promise if failure delete promises[uri]; }); }); promise.cacheCount = 1; promises[uri] = promise; return promise; } // remove the cached/loaded dicom dataset for the specified wadouri to free up memory function unload (uri) { const cornerstone = external.cornerstone; // console.log('unload for ' + uri); if (loadedDataSets[uri]) { loadedDataSets[uri].cacheCount--; if (loadedDataSets[uri].cacheCount === 0) { // console.log('removing loaded dataset for ' + uri); cacheSizeInBytes -= loadedDataSets[uri].dataSet.byteArray.length; delete loadedDataSets[uri]; cornerstone.triggerEvent(cornerstone.events, 'datasetscachechanged', { uri, action: 'unloaded', cacheInfo: getInfo() }); } } } export function getInfo () { return { cacheSizeInBytes, numberOfDataSetsCached: Object.keys(loadedDataSets).length }; } // removes all cached datasets from memory function purge () { loadedDataSets = {}; promises = {}; } export default { isLoaded, load, unload, getInfo, purge, get }; </code></pre> </article> </section> </div> <br class="clear"> <footer> Documentation generated by <a href="https://github.com/jsdoc3/jsdoc">JSDoc 3.5.5</a> using the <a href="https://github.com/clenemt/docdash">docdash</a> theme. </footer> <script>prettyPrint();</script> <script src="scripts/linenumber.js"></script> </body> </html>