Retrieved Hostlist information from Directory service.

remoting/test/hostlist_fetcher.cc

Index: remoting/test/hostlist_fetcher.cc
diff --git a/remoting/test/hostlist_fetcher.cc b/remoting/test/hostlist_fetcher.cc
new file mode 100644
index 0000000000000000000000000000000000000000..f1c904e8c07e9c508e70212ccb24fd78c360634e
--- /dev/null
+++ b/remoting/test/hostlist_fetcher.cc
@@ -0,0 +1,119 @@
+// Copyright 2015 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 "remoting/test/hostlist_fetcher.h"
+
+#include <iostream>

[joedow, 2015/07/01 03:39:35]

You should not be using iostream, use printf or DVLOG/LOG macros instead.  Why
was this included anyway?

[tonychun, 2015/07/06 20:11:51]

I put it in because I wanted to output the hostlist JSON message. printf has a
character limit (at least it did when I tried printing out the content to
screen).

I have removed it now.

+
+#include "base/bind.h"
+#include "base/callback_helpers.h"
+#include "base/json/json_reader.h"
+#include "base/logging.h"
+#include "base/message_loop/message_loop.h"

[joedow, 2015/07/01 03:39:34]

Where is message_loop used?  Remove it if not used.

[tonychun, 2015/07/06 20:11:50]

Done.

+#include "base/strings/stringprintf.h"

[joedow, 2015/07/01 03:39:35]

remove header and StringPrintf call since it isn't needed

[tonychun, 2015/07/06 20:11:51]

Done.

+#include "base/thread_task_runner_handle.h"
+#include "base/values.h"
+#include "net/http/http_response_headers.h"
+#include "net/http/http_status_code.h"
+#include "net/url_request/url_fetcher.h"
+#include "remoting/base/url_request_context_getter.h"
+
+namespace remoting {
+namespace test {
+
+HostlistFetcher::HostlistFetcher() {
+}
+
+HostlistFetcher::~HostlistFetcher() {
+}
+
+bool HostlistFetcher::RetrieveHostlist(const std::string& access_token,
+                                       ServiceEnvironment service_environment,
+                                       const HostlistCallback& callback) {
+  // Message the Directory service for the hostlist

[joedow, 2015/07/01 03:39:35]

I don't think this comment is useful, please remove.

[tonychun, 2015/07/06 20:11:51]

Done.

+  DVLOG(2) << "HostlistFetcher::RetrieveHostlist() called";
+

[joedow, 2015/07/01 03:39:35]

Please add some additional DCHECKS here.  You should validate that access_token
is not empty, service_environment is valid, callback is not null, and
hostlist_callback_ is null (i.e. you are not in the middle of a request).

[tonychun, 2015/07/06 20:11:51]

I removed service_environment because it is only targeting prod. I've added the
rest of the checks however.

+

[joedow, 2015/07/01 03:39:35]

Why so many empty newlines?  Please reduce to one.

[tonychun, 2015/07/06 20:11:51]

Done.

+
+  std::string service_url;
+  switch (service_environment) {
+    case kProductionEnvironment:
+      DVLOG(1) << "Configuring service request for prod environment";
+      service_url = base::StringPrintf(kProdServiceEnvironmentUrlFormat);

[joedow, 2015/07/01 03:39:35]

Why are you using StringPrintf here?  You aren't replacing any values.

[tonychun, 2015/07/06 20:11:50]

Done.

+      break;
+
+    default:
+      LOG(ERROR) << "Unrecognized service type: " << service_environment;
+      return false;
+  }
+
+  hostlist_callback_ = callback;
+
+  request_context_getter_ = new remoting::URLRequestContextGetter(
+      base::ThreadTaskRunnerHandle::Get(),   // network_runner
+      base::ThreadTaskRunnerHandle::Get());  // file_runner
+
+  request_ =
+      net::URLFetcher::Create(GURL(service_url), net::URLFetcher::GET, this);
+  request_->SetRequestContext(request_context_getter_.get());
+  request_->AddExtraRequestHeader("Authorization: OAuth " + access_token);
+  request_->SetUploadData("application/json; charset=UTF-8", "{}");

[joedow, 2015/07/01 03:39:35]

Is this line needed for this call?  I'm not sure this is used at all.

[tonychun, 2015/07/06 20:11:51]

Removed.

+  request_->Start();
+
+  return true;
+}
+
+void HostlistFetcher::OnURLFetchComplete(const net::URLFetcher* source) {
+  DCHECK(source);
+  DVLOG(2) << "URL Fetch Completed for: " << source->GetOriginalURL();
+
+  std::vector<ChromotingHostInfo> hostlist;
+  int response_code = request_->GetResponseCode();
+  if (response_code != net::HTTP_OK) {
+    LOG(ERROR) << "Hostlist request failed with error code: "
+               << response_code;
+    base::ResetAndReturn(&hostlist_callback_).Run(hostlist);

[joedow, 2015/07/01 03:39:35]

I think a ScopedClosureRunner() would make the multiple return statements
cleaner, you'd have to do a little work though to create a closure which binds
the hostlist param.  It would make everything cleaner though.

[tonychun, 2015/07/06 20:11:51]

Done.

+    return;
+  }
+
+  std::string response_string;
+  if (!request_->GetResponseAsString(&response_string)) {
+    LOG(ERROR) << "Failed to retrieve Hostlist response data";
+    base::ResetAndReturn(&hostlist_callback_).Run(hostlist);
+    return;
+  }
+
+  scoped_ptr<base::Value> response_value(
+      base::JSONReader::Read(response_string));
+  if (!response_value ||
+      !response_value->IsType(base::Value::TYPE_DICTIONARY)) {
+    LOG(ERROR) << "Failed to parse response string to JSON";
+    base::ResetAndReturn(&hostlist_callback_).Run(hostlist);
+    return;
+  }
+
+  const base::DictionaryValue* response;
+  if (!response_value->GetAsDictionary(&response)) {
+    LOG(ERROR) << "Failed to convert parsed JSON to a dictionary object";
+    base::ResetAndReturn(&hostlist_callback_).Run(hostlist);
+    return;
+  }
+
+  // add hosts to hostlist

[joedow, 2015/07/01 03:39:35]

Is this comment useful?  Please remove it or update it to conform to style guide
(Add hosts to hostlist.)

[tonychun, 2015/07/06 20:11:51]

Done.

+  const base::ListValue* items = nullptr;
+  response->GetList("data.items", &items);
+
+  int size = items->GetSize();

[joedow, 2015/07/01 03:39:35]

What if items is a nullptr, you should make sure it is valid before
dereferencing.

[tonychun, 2015/07/06 20:11:51]

Done.

+  DVLOG(1) << "There are " << size << " hosts in the hostlist";
+  const base::DictionaryValue* item;

[joedow, 2015/07/01 03:39:35]

it's a good idea to initialize pointers to nullptr even if you overwrite that
value.  Later on, the code may be moved around and a bug could be introduced.

[tonychun, 2015/07/06 20:11:51]

Done.

+  for (int i = 0; i < size; ++i) {
+    items->GetDictionary(i,&item);

[joedow, 2015/07/01 03:39:35]

add space between comma and ampersand (and run cpplint.py)

[tonychun, 2015/07/06 20:11:51]

Done.

+    hostlist.push_back(ChromotingHostInfo(*item));
+  }
+
+  base::ResetAndReturn(&hostlist_callback_).Run(hostlist);
+}
+
+}  // namespace test
+}  // namespace remoting