Start implementing an auth flow for platform apps to be able to do auth

chrome/browser/extensions/api/identity/web_auth_flow.cc

+// Copyright (c) 2012 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/extensions/api/identity/web_auth_flow.h"
+
+#include "base/bind.h"
+#include "base/command_line.h"
+#include "base/location.h"
+#include "base/message_loop.h"
+#include "base/stringprintf.h"
+#include "base/string_util.h"
+#include "chrome/common/chrome_switches.h"
+#include "content/public/browser/invalidate_type.h"
+#include "content/public/browser/navigation_controller.h"
+#include "content/public/browser/web_contents.h"
+#include "ipc/ipc_message.h"
+
+using content::BrowserContext;
+using content::WebContents;
+using content::WebContentsDelegate;
+
+namespace {
+
+static const char kChromeExtensionSchemeUrlPattern[] =
+    "chrome-extension://%s/";
+static const char kChromiumDomainRedirectUrlPattern[] =
+    "https://%s.chromiumapp.org/";
+
+extensions::WebAuthFlow::InterceptorForTests* g_interceptor_for_tests = NULL;
+
+}  // namespace
+
+namespace extensions {
+
+// static
+void WebAuthFlow::SetInterceptorForTests(InterceptorForTests* interceptor) {
+  CHECK(CommandLine::ForCurrentProcess()->HasSwitch(switches::kTestType));
+  CHECK(NULL == g_interceptor_for_tests);  // Only one at a time.
+  g_interceptor_for_tests = interceptor;
+}
+
+WebAuthFlow::WebAuthFlow(
+    Delegate* delegate,
+    BrowserContext* browser_context,
+    const std::string& extension_id,
+    const GURL& provider_url)
+    : delegate_(delegate),
+      browser_context_(browser_context),
+      provider_url_(provider_url),
+      contents_(NULL),
+      window_(NULL) {
+  InitValidRedirectUrlPrefixes(extension_id);
+}
+
+WebAuthFlow::~WebAuthFlow() {
+  if (window_)
+    delete window_;
+  if (contents_) {
+    contents_->SetDelegate(NULL);
+    contents_->Stop();
+    // Tell message loop to delete contents_ instead of deleting it
+    // directly since destructor can run in response to a callback from
+    // contents_.
+    MessageLoop::current()->DeleteSoon(FROM_HERE, contents_);
+  }
+}
+
+void WebAuthFlow::Start() {
+  if (g_interceptor_for_tests != NULL) {
+    // We use PostTask, instead of calling the delegate directly, because the
+    // message loop will run a few times before we notify the delegate in the
+    // real implementation.
+    GURL result = g_interceptor_for_tests->DoIntercept(provider_url_);
+    MessageLoop::current()->PostTask(
+        FROM_HERE,
+        base::Bind(&WebAuthFlow::ReportResult,
+                   base::Unretained(this), result));
+    return;
+  }
+
+  contents_ = CreateWebContents();
+  contents_->SetDelegate(this);
+  contents_->GetController().LoadURL(
+      provider_url_,
+      content::Referrer(),
+      content::PAGE_TRANSITION_START_PAGE,
+      std::string());
+}
+
+void WebAuthFlow::LoadingStateChanged(WebContents* source) {
+  if (source->IsLoading())
+    return;
+  OnUrlLoaded();
+}
+
+void WebAuthFlow::NavigationStateChanged(
+    const WebContents* source, unsigned changed_flags) {
+  // If the URL has not changed, do not perform the check again (for
+  // efficiency).
+  if ((changed_flags & content::INVALIDATE_TYPE_URL) == 0)
+    return;
+
+  // If the URL is a valid extension redirect URL, capture the
+  // results and end the flow.
+  const GURL& url = source->GetURL();
+
+  if (IsValidRedirectUrl(url)) {
+    ReportResult(url);
+    return;
+  }
+}
+
+WebContents* WebAuthFlow::CreateWebContents() {
+  return WebContents::Create(
+      browser_context_, NULL, MSG_ROUTING_NONE, NULL, NULL);
+}
+
+WebAuthFlowWindow* WebAuthFlow::CreateAuthWindow() {
+  return WebAuthFlowWindow::Create(this, browser_context_, contents_);
+}
+
+void WebAuthFlow::OnUrlLoaded() {
+  if (!window_) {
+    window_ = CreateAuthWindow();
+    // TODO(munjal): Remove this null check once we have implementations
+    // of WebAuthFlowWindow on all platforms.
+    if (!window_)
+      ReportResult(GURL());
+    else
+      window_->Show();
+  }
+}
+
+void WebAuthFlow::OnClose() {
+  ReportResult(GURL());
+}
+
+void WebAuthFlow::ReportResult(const GURL& result) {
+  if (!delegate_)
+    return;
+
+  if (result.is_empty()) {
+    delegate_->OnAuthFlowFailure();
+  } else {
+    // TODO(munjal): Consider adding code to parse out access token
+    // from some common places (e.g. URL fragment) so the apps don't
+    // have to do that work.
+    delegate_->OnAuthFlowSuccess(result.spec());
+  }
+
+  // IMPORTANT: Do not access any members after calling the delegate
+  // since the delegate can destroy |this| in the callback and hence
+  // all data members are invalid after that.
+}
+
+void WebAuthFlow::InitValidRedirectUrlPrefixes(
+    const std::string& extension_id) {
+  valid_prefixes_.push_back(base::StringPrintf(
+      kChromeExtensionSchemeUrlPattern, extension_id.c_str()));
+  valid_prefixes_.push_back(base::StringPrintf(
+      kChromiumDomainRedirectUrlPattern, extension_id.c_str()));
+}
+
+bool WebAuthFlow::IsValidRedirectUrl(const GURL& url) const {
+  std::vector<std::string>::const_iterator iter;
+  for (iter = valid_prefixes_.begin(); iter != valid_prefixes_.end(); ++iter) {
+    if (StartsWithASCII(url.spec(), *iter, false))
+      return true;
+  }
+  return false;
+}
+
+}  // namespace extensions