feat(dcmjs):Support singlepart responses

Author: wayfarer3130

README.md

@@ -49,6 +49,11 @@ client.searchForStudies().then(studies => {
 });
 ```
 
+## Configuration Options
+The API can be configured with a number of custom configuration options to control the requests.  These are:
+* url to retrieve from for the base requests
+* singlepart, either true or a set of parts from `bulkdata,image,video` to request as single part responses
+* headers to add to the retrieve
 
 ## For maintainers
 

src/api.js

@@ -58,6 +58,8 @@ class DICOMwebClient {
    * @param {Object} options.headers - HTTP headers
    * @param {Array.<RequestHook>} options.requestHooks - Request hooks.
    * @param {Object} options.verbose - print to console request warnings and errors, default true
+   * @param {boolean|String} options.singlepart - retrieve singlepart for the named types.
+   * The available types are:  bulkdata, video, image.  true means all.
    */
   constructor(options) {
     this.baseURL = options.url;
@@ -96,6 +98,13 @@ class DICOMwebClient {
       this.stowURL = this.baseURL;
     }
 
+    if (options.singlepart) {
+      console.log('use singlepart', options.singlepart);
+      this.singlepart = options.singlepart === true ? 'bulkdata,video,image' : options.singlepart;
+    } else {
+      this.singlepart = '';
+    }
+
     if ('requestHooks' in options) {
       this.requestHooks = options.requestHooks;
     }
@@ -188,7 +197,16 @@ class DICOMwebClient {
       request.onreadystatechange = () => {
         if (request.readyState === 4) {
           if (request.status === 200) {
-            resolve(request.response);
+            const contentType = request.getResponseHeader('Content-Type');
+            // Automatically distinguishes between multipart and singlepart in an array buffer, and
+            // converts them into a consistent type.
+            if (contentType && contentType.indexOf('multipart') !== -1) {
+              resolve(multipartDecode(request.response));
+            } else if (request.responseType === 'arraybuffer') {
+              resolve([request.response]);
+            } else {
+              resolve(request.response);
+            }
           } else if (request.status === 202) {
             if (this.verbose) {
               console.warn('some resources already existed: ', request);
@@ -536,9 +554,7 @@ class DICOMwebClient {
       supportedMediaTypes,
     );
 
-    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials).then(
-      multipartDecode,
-    );
+    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials);
   }
 
   /**
@@ -594,9 +610,7 @@ class DICOMwebClient {
       supportedMediaTypes,
     );
 
-    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials).then(
-      multipartDecode,
-    );
+    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials);
   }
 
   /**
@@ -646,9 +660,7 @@ class DICOMwebClient {
       supportedMediaTypes,
     );
 
-    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials).then(
-      multipartDecode,
-    );
+    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials);
   }
 
   /**
@@ -692,9 +704,7 @@ class DICOMwebClient {
       supportedMediaTypes,
     );
 
-    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials).then(
-      multipartDecode,
-    );
+    return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials);
   }
 
   /**
@@ -1237,9 +1247,7 @@ class DICOMwebClient {
           supportedMediaTypes,
         ),
       };
-      return this._httpGet(
-        url, headers, 'arraybuffer', progressCallback, withCredentials,
-      ).then(multipartDecode);
+      return this._httpGet(url, headers, 'arraybuffer', progressCallback, withCredentials);
     }
 
     const commonMediaType = DICOMwebClient._getCommonMediaType(mediaTypes);
@@ -1715,7 +1723,9 @@ class DICOMwebClient {
    * See http://dicom.nema.org/medical/dicom/current/output/chtml/part18/sect_6.5.5.html
    *
    * @param {Object} options
-   * @param {String} BulkDataURI - URI for retrieval of bulkdata
+   * @param {string} options.BulkDataURI to retrieve
+   * @param {Array}  options.mediaTypes to use to fetch the URI
+   * @param {string} options.byteRange to request a sub-range (only valid on single part)
    * @returns {Promise<Array>} Bulkdata parts
    */
   retrieveBulkData(options) {
@@ -1728,6 +1738,10 @@ class DICOMwebClient {
     const { withCredentials = false } = options;
     const { progressCallback = false } = options;
 
+    if (this.singlepart.indexOf('bulkdata') !== -1) {
+      return this._httpGet(url, options.headers, 'arraybuffer', null, withCredentials);
+    }
+
     if (!mediaTypes) {
       return this._httpGetMultipartApplicationOctetStream(
         url,

src/message.js

@@ -184,7 +184,8 @@ function multipartEncode(
  * @returns {Array} The content
  */
 function multipartDecode(response) {
-  const message = new Uint8Array(response);
+  // Use the raw data if it is provided in an appropriate format
+  const message = ArrayBuffer.isView(response) ? response : new Uint8Array(response);
 
   /* Set a maximum length to search for the header boundaries, otherwise
        findToken can run for a long time