Add the most recent crash report IDs to feedback reports

chrome/browser/feedback/system_logs/log_sources/crash_ids_source.cc

Index: chrome/browser/feedback/system_logs/log_sources/crash_ids_source.cc
diff --git a/chrome/browser/feedback/system_logs/log_sources/crash_ids_source.cc b/chrome/browser/feedback/system_logs/log_sources/crash_ids_source.cc
new file mode 100644
index 0000000000000000000000000000000000000000..9363cb614ef48e7448d637f69cb44db3fb527ab6
--- /dev/null
+++ b/chrome/browser/feedback/system_logs/log_sources/crash_ids_source.cc
@@ -0,0 +1,81 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/feedback/system_logs/log_sources/crash_ids_source.h"
+
+#include <string>
+
+#include "base/bind.h"
+#include "base/time/time.h"
+#include "chrome/browser/crash_upload_list/crash_upload_list.h"
+
+namespace system_logs {
+
+namespace {
+
+// The ID of the product specific data as stored by the feedback server.
+constexpr char kCrashReportIds[] = "crash_report_ids";
+
+// The maximum number of crashes we retrieve from the crash list.
+constexpr size_t kMaxCrashesCountToRetrieve = 10;
+
+// We are only interested in crashes that took place within the last hour.
+constexpr base::TimeDelta kOneHourTimeDelta = base::TimeDelta::FromHours(1);
+
+}  // namespace
+
+CrashIdsSource::CrashIdsSource()
+    : SystemLogsSource("CrashId"),
+      crash_upload_list_(CreateCrashUploadList(this)),

[Rahul Chaturvedi, 2016/09/08 19:58:24]

What happens if the system logs fetcher is deleted before we get a callback on
OnUploadListAvailable?
Should this be a weak_ptr instead?

[afakhry, 2016/09/09 22:20:10]

We can make it a weak_ptr, but is it really needed?
The SystemLogsFetcher is a self-deleting object that gets deleted only when all
the responses from all log sources have been received:
https://cs.chromium.org/chromium/src/chrome/browser/feedback/system_logs/syst...

[Rahul Chaturvedi, 2016/09/12 22:31:21]

Ah - in that case just document that below where we call
LoadUploadListAsynchronously(), that we currently outlive that call and need to
in the future too.

+      pending_crash_list_loading_(false) {}
+
+CrashIdsSource::~CrashIdsSource() {}
+
+void CrashIdsSource::Fetch(const SysLogsSourceCallback& callback) {
+  // Unretained since we own these callbacks.
+  pending_requests_.emplace_back(base::Bind(
+      &CrashIdsSource::RespondWithCrashIds, base::Unretained(this), callback));
+
+  if (pending_crash_list_loading_)
+    return;
+
+  pending_crash_list_loading_ = true;
+  crash_upload_list_->LoadUploadListAsynchronously();
+}
+
+void CrashIdsSource::OnUploadListAvailable() {
+  pending_crash_list_loading_ = false;
+
+  // Only get the IDs of crashes that occurred within the last hour (if any).
+  std::vector<UploadList::UploadInfo> crashes;
+  crash_upload_list_->GetUploads(kMaxCrashesCountToRetrieve, &crashes);
+  const base::Time now = base::Time::Now();
+  crash_ids_list_.clear();
+  crash_ids_list_.reserve(kMaxCrashesCountToRetrieve);
+
+  // The feedback server expects the crash IDs to be a comma-separated list.
+  for (const auto& crash_info : crashes) {
+    if (now - crash_info.capture_time < kOneHourTimeDelta) {
+      const std::string& crash_id = crash_info.upload_id;
+      crash_ids_list_.append(crash_ids_list_.empty() ? crash_id
+                                                     : ", " + crash_id);
+    }
+  }
+
+  for (const auto& request : pending_requests_)
+    request.Run();
+
+  pending_requests_.clear();
+}
+
+void CrashIdsSource::RespondWithCrashIds(
+    const SysLogsSourceCallback& callback) const {
+  std::unique_ptr<SystemLogsResponse> response(new SystemLogsResponse());
+  (*response)[kCrashReportIds] = crash_ids_list_;
+
+  // We must respond anyways.
+  callback.Run(response.get());
+}
+
+}  // namespace system_logs