From bef7d5a520c5eedfae38bd1237e0d3526f2db56e Mon Sep 17 00:00:00 2001
From: Hari Krishna Reddy Juturu <jhreddy@microsoft.com>
Date: Mon, 17 Apr 2017 04:59:16 -0700
Subject: [PATCH] API to get memory of all processes of the app

---
 atom/browser/api/atom_api_app.cc | 35 +++++++++++++++++++++++++++++++-
 atom/browser/api/atom_api_app.h  | 14 +++++++++++++
 docs/api/app.md                  | 17 ++++++++++++++++
 3 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/atom/browser/api/atom_api_app.cc b/atom/browser/api/atom_api_app.cc
index 115041d0082d..a990b5c1bd30 100644
--- a/atom/browser/api/atom_api_app.cc
+++ b/atom/browser/api/atom_api_app.cc
@@ -912,6 +912,38 @@ void App::GetFileIcon(const base::FilePath& path,
   }
 }
 
+v8::Local<v8::Value> App::GetAppMemoryInfo(v8::Isolate* isolate) {
+  AppIdProcessIterator processIterator;
+  auto processEntry = processIterator.NextProcessEntry();
+  mate::Dictionary result = mate::Dictionary::CreateEmpty(isolate);
+
+  while(processEntry != nullptr) {
+    int64_t pid = processEntry->pid();
+    auto process = base::Process::OpenWithExtraPrivileges(pid);
+
+    std::unique_ptr<base::ProcessMetrics> metrics(
+      base::ProcessMetrics::CreateProcessMetrics(process.Handle()));
+
+    mate::Dictionary dict = mate::Dictionary::CreateEmpty(isolate);
+    
+    dict.Set("workingSetSize",
+            static_cast<double>(metrics->GetWorkingSetSize() >> 10));
+    dict.Set("peakWorkingSetSize",
+            static_cast<double>(metrics->GetPeakWorkingSetSize() >> 10));
+
+    size_t private_bytes, shared_bytes;
+    if (metrics->GetMemoryBytes(&private_bytes, &shared_bytes)) {
+      dict.Set("privateBytes", static_cast<double>(private_bytes >> 10));
+      dict.Set("sharedBytes", static_cast<double>(shared_bytes >> 10));
+    }
+
+    result.Set(std::to_string(pid).c_str(), dict); 
+    processEntry = processIterator.NextProcessEntry();
+  }
+
+  return result.GetHandle();
+}
+
 // static
 mate::Handle<App> App::Create(v8::Isolate* isolate) {
   return mate::CreateHandle(isolate, new App(isolate));
@@ -983,7 +1015,8 @@ void App::BuildPrototype(
                  &App::IsAccessibilitySupportEnabled)
       .SetMethod("disableHardwareAcceleration",
                  &App::DisableHardwareAcceleration)
-      .SetMethod("getFileIcon", &App::GetFileIcon);
+      .SetMethod("getFileIcon", &App::GetFileIcon)
+      .SetMethod("getAppMemoryInfo", &App::GetAppMemoryInfo);
 }
 
 }  // namespace api
diff --git a/atom/browser/api/atom_api_app.h b/atom/browser/api/atom_api_app.h
index a87b88bc4642..9c35d91af720 100644
--- a/atom/browser/api/atom_api_app.h
+++ b/atom/browser/api/atom_api_app.h
@@ -13,6 +13,7 @@
 #include "atom/browser/browser.h"
 #include "atom/browser/browser_observer.h"
 #include "atom/common/native_mate_converters/callback.h"
+#include "base/process/process_iterator.h"
 #include "base/task/cancelable_task_tracker.h"
 #include "chrome/browser/icon_manager.h"
 #include "chrome/browser/process_singleton.h"
@@ -141,6 +142,8 @@ class App : public AtomBrowserClient::Delegate,
   void GetFileIcon(const base::FilePath& path,
                    mate::Arguments* args);
 
+  v8::Local<v8::Value> GetAppMemoryInfo(v8::Isolate* isolate);
+
 #if defined(OS_WIN)
   // Get the current Jump List settings.
   v8::Local<v8::Value> GetJumpListSettings();
@@ -163,6 +166,17 @@ class App : public AtomBrowserClient::Delegate,
   DISALLOW_COPY_AND_ASSIGN(App);
 };
 
+class AppIdProcessIterator : public base::ProcessIterator {
+ public:
+  AppIdProcessIterator() : base::ProcessIterator(NULL) {}
+
+ protected:
+  bool IncludeEntry() override {
+    return (entry().parent_pid() == base::GetCurrentProcId() ||
+            entry().pid() == base::GetCurrentProcId());
+  }
+};
+
 }  // namespace api
 
 }  // namespace atom
diff --git a/docs/api/app.md b/docs/api/app.md
index e3160e9053f8..facc18ec389e 100644
--- a/docs/api/app.md
+++ b/docs/api/app.md
@@ -760,6 +760,23 @@ Disables hardware acceleration for current app.
 
 This method can only be called before app is ready.
 
+### `app.getAppMemoryInfo()`
+
+Returns `Object[]`:
+
+* `pid` Integer - The process id for which memory info is collected for
+  * `workingSetSize` Integer - The amount of memory currently pinned to actual physical
+    RAM.
+  * `peakWorkingSetSize` Integer - The maximum amount of memory that has ever been pinned
+    to actual physical RAM.
+  * `privateBytes` Integer - The amount of memory not shared by other processes, such as
+    JS heap or HTML content.
+  * `sharedBytes` Integer - The amount of memory shared between processes, typically
+    memory consumed by the Electron code itself
+
+Returns an object giving memory usage statistics about all the processes associated with 
+the app. Note that all statistics are reported in Kilobytes.
+
 ### `app.setBadgeCount(count)` _Linux_ _macOS_
 
 * `count` Integer