Merge pull request #6952 from deepak1556/custom_scheme_filesystem_patch

protocol: allow standard schemes to support filesystem api

atom/browser/atom_browser_client.cc

@@ -9,6 +9,7 @@
 #endif
 
 #include "atom/browser/api/atom_api_app.h"
+#include "atom/browser/api/atom_api_protocol.h"
 #include "atom/browser/atom_access_token_store.h"
 #include "atom/browser/atom_browser_context.h"
 #include "atom/browser/atom_browser_main_parts.h"
@@ -23,8 +24,8 @@
 #include "base/command_line.h"
 #include "base/files/file_util.h"
 #include "base/stl_util.h"
-#include "base/strings/string_util.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "chrome/browser/printing/printing_message_filter.h"
 #include "chrome/browser/renderer_host/pepper/chrome_browser_pepper_host_factory.h"
 #include "chrome/browser/renderer_host/pepper/widevine_cdm_message_filter.h"
@@ -279,6 +280,15 @@ bool AtomBrowserClient::CanCreateWindow(
   return false;
 }
 
+void AtomBrowserClient::GetAdditionalAllowedSchemesForFileSystem(
+    std::vector<std::string>* additional_schemes) {
+  auto schemes_list = api::GetStandardSchemes();
+  if (!schemes_list.empty())
+    additional_schemes->insert(additional_schemes->end(),
+                               schemes_list.begin(),
+                               schemes_list.end());
+}
+
 brightray::BrowserMainParts* AtomBrowserClient::OverrideCreateBrowserMainParts(
     const content::MainFunctionParams&) {
   v8::V8::Initialize();  // Init V8 before creating main parts.

atom/browser/atom_browser_client.h

@@ -94,6 +94,8 @@ class AtomBrowserClient : public brightray::BrowserClient,
                        int opener_render_view_id,
                        int opener_render_frame_id,
                        bool* no_javascript_access) override;
+  void GetAdditionalAllowedSchemesForFileSystem(
+      std::vector<std::string>* schemes) override;
 
   // brightray::BrowserClient:
   brightray::BrowserMainParts* OverrideCreateBrowserMainParts(

docs/api/protocol.md

@@ -48,8 +48,10 @@ non-standard schemes can not recognize relative URLs:
 </body>
 ```
 
-So if you want to register a custom protocol to replace the `http` protocol, you
-have to register it as standard scheme:
+Registering a scheme as standard will allow access to files through the
+[FileSystem API][file-system-api]. Otherwise the renderer will throw a security
+error for the scheme. So in general if you want to register a custom protocol to
+replace the `http` protocol, you have to register it as a standard scheme:
 
 ```javascript
 const {app, protocol} = require('electron')
@@ -228,3 +230,4 @@ which sends a new HTTP request as a response.
 Remove the interceptor installed for `scheme` and restore its original handler.
 
 [net-error]: https://code.google.com/p/chromium/codesearch#chromium/src/net/base/net_error_list.h
+[file-system-api]: https://developer.mozilla.org/en-US/docs/Web/API/LocalFileSystem

spec/api-protocol-spec.js

@@ -4,7 +4,7 @@ const path = require('path')
 const qs = require('querystring')
 const {closeWindow} = require('./window-helpers')
 const remote = require('electron').remote
-const {BrowserWindow, protocol, webContents} = remote
+const {BrowserWindow, ipcMain, protocol, webContents} = remote
 
 describe('protocol module', function () {
   var protocolName = 'sp'
@@ -965,5 +965,18 @@ describe('protocol module', function () {
         w.loadURL(origin)
       })
     })
+
+    it('can access files through the FileSystem API', function (done) {
+      let filePath = path.join(__dirname, 'fixtures', 'pages', 'filesystem.html')
+      const handler = function (request, callback) {
+        callback({path: filePath})
+      }
+      protocol.registerFileProtocol(standardScheme, handler, function (error) {
+        if (error) return done(error)
+        w.loadURL(origin)
+      })
+      ipcMain.once('file-system-error', (event, err) => done(err))
+      ipcMain.once('file-system-write-end', () => done())
+    })
   })
 })

spec/fixtures/pages/filesystem.html

@@ -0,0 +1,24 @@
+<script>
+const {ipcRenderer} = require('electron')
+function onInitFs (fs) {
+  fs.root.getFile('log.txt', {create: true}, function (fileEntry) {
+    fileEntry.createWriter(function (fileWriter) {
+      var blob = new Blob(['Lorem Ipsum'], {type: 'text/plain'});
+      fileWriter.onwriteend = function() {
+        ipcRenderer.send('file-system-write-end')
+      };
+      fileWriter.onerror = errorHandler
+      fileWriter.write(blob);
+    }, errorHandler);
+  }, errorHandler);
+
+}
+
+navigator.webkitPersistentStorage.requestQuota(5 * 1024 * 1024, function (granted) {
+  webkitRequestFileSystem(TEMPORARY, granted, onInitFs, errorHandler);
+}, errorHandler)
+
+function errorHandler(e) {
+  ipcRenderer.send('file-system-error', e)
+}
+</script>