feat: promisify session.getBlobData()

atom/browser/api/atom_api_session.cc

@@ -660,16 +660,17 @@ std::string Session::GetUserAgent() {
   return browser_context_->GetUserAgent();
 }
 
-void Session::GetBlobData(const std::string& uuid,
-                          const AtomBlobReader::CompletionCallback& callback) {
-  if (callback.is_null())
-    return;
+v8::Local<v8::Promise> Session::GetBlobData(const std::string& uuid) {
+  v8::Isolate* isolate = v8::Isolate::GetCurrent();
+  util::Promise promise(isolate);
+  v8::Local<v8::Promise> handle = promise.GetHandle();
 
   AtomBlobReader* blob_reader = browser_context()->GetBlobReader();
   base::PostTaskWithTraits(
       FROM_HERE, {BrowserThread::IO},
       base::BindOnce(&AtomBlobReader::StartReading,
-                     base::Unretained(blob_reader), uuid, callback));
+                     base::Unretained(blob_reader), uuid, std::move(promise)));
+  return handle;
 }
 
 void Session::CreateInterruptedDownload(const mate::Dictionary& options) {

atom/browser/api/atom_api_session.h

@@ -82,8 +82,7 @@ class Session : public mate::TrackableObject<Session>,
   void AllowNTLMCredentialsForDomains(const std::string& domains);
   void SetUserAgent(const std::string& user_agent, mate::Arguments* args);
   std::string GetUserAgent();
-  void GetBlobData(const std::string& uuid,
-                   const AtomBlobReader::CompletionCallback& callback);
+  v8::Local<v8::Promise> GetBlobData(const std::string& uuid);
   void CreateInterruptedDownload(const mate::Dictionary& options);
   void SetPreloads(const std::vector<base::FilePath::StringType>& preloads);
   std::vector<base::FilePath::StringType> GetPreloads() const;

atom/browser/atom_blob_reader.cc

@@ -28,22 +28,22 @@ void FreeNodeBufferData(char* data, void* hint) {
   delete[] data;
 }
 
-void RunCallbackInUI(const AtomBlobReader::CompletionCallback& callback,
-                     char* blob_data,
-                     int size) {
+void RunPromiseInUI(const atom::util::CopyablePromise& promise,
+                    char* blob_data,
+                    int size) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  v8::Isolate* isolate = promise.GetPromise().isolate();
 
-  v8::Isolate* isolate = v8::Isolate::GetCurrent();
   v8::Locker locker(isolate);
   v8::HandleScope handle_scope(isolate);
   if (blob_data) {
     v8::Local<v8::Value> buffer =
         node::Buffer::New(isolate, blob_data, static_cast<size_t>(size),
                           &FreeNodeBufferData, nullptr)
             .ToLocalChecked();
-    callback.Run(buffer);
+    promise.GetPromise().Resolve(buffer);
   } else {
-    callback.Run(v8::Null(isolate));
+    promise.GetPromise().RejectWithErrorMessage("Could not get blob data");
   }
 }
 
@@ -54,22 +54,21 @@ AtomBlobReader::AtomBlobReader(content::ChromeBlobStorageContext* blob_context)
 
 AtomBlobReader::~AtomBlobReader() {}
 
-void AtomBlobReader::StartReading(
-    const std::string& uuid,
-    const AtomBlobReader::CompletionCallback& completion_callback) {
+void AtomBlobReader::StartReading(const std::string& uuid,
+                                  atom::util::Promise promise) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   auto blob_data_handle = blob_context_->context()->GetBlobDataFromUUID(uuid);
-  auto callback = base::Bind(&RunCallbackInUI, completion_callback);
   if (!blob_data_handle) {
-    base::PostTaskWithTraits(FROM_HERE, {BrowserThread::UI},
-                             base::BindOnce(callback, nullptr, 0));
+    atom::util::Promise::RejectPromise(std::move(promise),
+                                       "Could not get blob data handle");
     return;
   }
 
   auto blob_reader = blob_data_handle->CreateReader();
-  BlobReadHelper* blob_read_helper =
-      new BlobReadHelper(std::move(blob_reader), callback);
+  BlobReadHelper* blob_read_helper = new BlobReadHelper(
+      std::move(blob_reader),
+      base::Bind(&RunPromiseInUI, atom::util::CopyablePromise(promise)));
   blob_read_helper->Read();
 }
 

atom/browser/atom_blob_reader.h

@@ -8,6 +8,7 @@
 #include <memory>
 #include <string>
 
+#include "atom/common/promise_util.h"
 #include "base/callback.h"
 
 namespace content {
@@ -35,13 +36,10 @@ namespace atom {
 // except Ctor are expected to be called on IO thread.
 class AtomBlobReader {
  public:
-  using CompletionCallback = base::Callback<void(v8::Local<v8::Value>)>;
-
   explicit AtomBlobReader(content::ChromeBlobStorageContext* blob_context);
   ~AtomBlobReader();
 
-  void StartReading(const std::string& uuid,
-                    const AtomBlobReader::CompletionCallback& callback);
+  void StartReading(const std::string& uuid, atom::util::Promise promise);
 
  private:
   // A self-destroyed helper class to read the blob data.

docs/api/promisification.md

@@ -13,7 +13,6 @@ When a majority of affected functions are migrated, this flag will be enabled by
 - [dialog.showCertificateTrustDialog([browserWindow, ]options, callback)](https://github.com/electron/electron/blob/master/docs/api/dialog.md#showCertificateTrustDialog)
 - [inAppPurchase.purchaseProduct(productID, quantity, callback)](https://github.com/electron/electron/blob/master/docs/api/in-app-purchase.md#purchaseProduct)
 - [inAppPurchase.getProducts(productIDs, callback)](https://github.com/electron/electron/blob/master/docs/api/in-app-purchase.md#getProducts)
-- [ses.getBlobData(identifier, callback)](https://github.com/electron/electron/blob/master/docs/api/session.md#getBlobData)
 - [contents.executeJavaScript(code[, userGesture, callback])](https://github.com/electron/electron/blob/master/docs/api/web-contents.md#executeJavaScript)
 - [contents.print([options], [callback])](https://github.com/electron/electron/blob/master/docs/api/web-contents.md#print)
 - [webFrame.executeJavaScript(code[, userGesture, callback])](https://github.com/electron/electron/blob/master/docs/api/web-frame.md#executeJavaScript)
@@ -47,6 +46,7 @@ When a majority of affected functions are migrated, this flag will be enabled by
 - [ses.getCacheSize(callback)](https://github.com/electron/electron/blob/master/docs/api/session.md#getCacheSize)
 - [ses.clearAuthCache(options[, callback])](https://github.com/electron/electron/blob/master/docs/api/session.md#clearAuthCache)
 - [ses.clearCache(callback)](https://github.com/electron/electron/blob/master/docs/api/session.md#clearCache)
+- [ses.getBlobData(identifier, callback)](https://github.com/electron/electron/blob/master/docs/api/session.md#getBlobData)
 - [shell.openExternal(url[, options, callback])](https://github.com/electron/electron/blob/master/docs/api/shell.md#openExternal)
 - [webviewTag.capturePage([rect, ]callback)](https://github.com/electron/electron/blob/master/docs/api/webview-tag.md#capturePage)
 - [webviewTag.printToPDF(options, callback)](https://github.com/electron/electron/blob/master/docs/api/webview-tag.md#printToPDF)

docs/api/session.md

@@ -512,6 +512,14 @@ Returns `String` - The user agent for this session.
 * `callback` Function
   * `result` Buffer - Blob data.
 
+**[Deprecated Soon](promisification.md)**
+
+#### `ses.getBlobData(identifier)`
+
+* `identifier` String - Valid UUID.
+
+Returns `Promise<Buffer>` - resolves with blob data.
+
 #### `ses.createInterruptedDownload(options)`
 
 * `options` Object

lib/browser/api/session.js

@@ -30,6 +30,7 @@ Session.prototype.setProxy = deprecate.promisify(Session.prototype.setProxy)
 Session.prototype.getCacheSize = deprecate.promisify(Session.prototype.getCacheSize)
 Session.prototype.clearCache = deprecate.promisify(Session.prototype.clearCache)
 Session.prototype.clearAuthCache = deprecate.promisify(Session.prototype.clearAuthCache)
+Session.prototype.getBlobData = deprecate.promisifyMultiArg(Session.prototype.getBlobData)
 
 Cookies.prototype.flushStore = deprecate.promisify(Cookies.prototype.flushStore)
 Cookies.prototype.get = deprecate.promisify(Cookies.prototype.get)

spec/api-session-spec.js

@@ -774,7 +774,7 @@ describe('session module', () => {
     })
   })
 
-  describe('ses.getBlobData(identifier, callback)', () => {
+  describe('ses.getBlobData()', () => {
     it('returns blob data for uuid', (done) => {
       const scheme = 'cors-blob'
       const protocol = session.defaultSession.protocol
@@ -811,7 +811,7 @@ describe('session module', () => {
         } else if (request.method === 'POST') {
           const uuid = request.uploadData[1].blobUUID
           assert(uuid)
-          session.defaultSession.getBlobData(uuid, (result) => {
+          const result = session.defaultSession.getBlobData(uuid).then(result => {
             assert.strictEqual(result.toString(), postData)
             done()
           })