Add a flow class to abstract all the details of minting a token for an app.

chrome/common/net/gaia/oauth2_mint_token_flow.h

Index: chrome/common/net/gaia/oauth2_mint_token_flow.h
===================================================================
--- chrome/common/net/gaia/oauth2_mint_token_flow.h	(revision 0)
+++ chrome/common/net/gaia/oauth2_mint_token_flow.h	(revision 0)
@@ -0,0 +1,126 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.

[asargent_no_longer_on_chrome, 2012/03/03 00:09:31]

2012 strikes again! Sneaky bugger

[Munjal (Google), 2012/03/03 00:48:42]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FLOW_H_
+#define CHROME_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FLOW_H_
+
+#include <string>
+
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "chrome/common/net/gaia/oauth2_access_token_consumer.h"
+#include "chrome/common/net/gaia/oauth2_access_token_fetcher.h"
+#include "chrome/common/net/gaia/oauth2_mint_token_consumer.h"
+#include "chrome/common/net/gaia/oauth2_mint_token_fetcher.h"
+
+class GoogleServiceAuthError;
+class OAuth2MintTokenFlowTest;
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+// This class implements the OAuth2 flow to Google to mint an OAuth2
+// token for the given client and the given set of scopes from the
+// OAuthLogin scoped "master" OAuth2 token for the user logged in to
+// Chrome.
+class OAuth2MintTokenFlow
+    : public OAuth2AccessTokenConsumer,
+      public OAuth2MintTokenConsumer {
+ public:
+  class Delegate {
+   public:
+    virtual void OnMintTokenSuccess(const std::string& access_token) { }
+    virtual void OnMintTokenFailure(const GoogleServiceAuthError& error) { }
+  };
+
+  OAuth2MintTokenFlow(net::URLRequestContextGetter* context,
+                      Delegate* delegate);
+  virtual ~OAuth2MintTokenFlow();
+
+  // Start the process to mint a token.
+  void Start(const std::string& login_refresh_token,
+             const std::string& extension_id,
+             const std::string& client_id,
+             const std::vector<std::string>& scopes);
+
+  // OAuth2AccessTokenConsumer implementation.
+  virtual void OnGetTokenSuccess(const std::string& access_token) OVERRIDE;
+  virtual void OnGetTokenFailure(const GoogleServiceAuthError& error) OVERRIDE;
+  // OAuth2MintTokenConsumer implementation.
+  virtual void OnMintTokenSuccess(const std::string& access_token) OVERRIDE;
+  virtual void OnMintTokenFailure(const GoogleServiceAuthError& error) OVERRIDE;
+
+  // Getters for various members.
+  const std::string& extension_id() const { return extension_id_; }
+  const std::string& client_id() const { return client_id_; }
+
+ protected:
+  // Helper to create an instnace of access token fetcher.

[asargent_no_longer_on_chrome, 2012/03/03 00:09:31]

typo: "instnace"

[Munjal (Google), 2012/03/03 00:48:42]

Done.

+  // Caller owns the returned instance.
+  virtual OAuth2AccessTokenFetcher* CreateAccessTokenFetcher();
+
+  // Helper to create an instnace of mint token fetcher.
+  // Caller owns the returned instance.
+  virtual OAuth2MintTokenFetcher* CreateMintTokenFetcher();
+
+ private:
+  // The steps this class performs are:
+  // 1. Create a login scoped access token from login scoped refresh token.
+  // 2. Use login scoped access token to call the API to mint an access token
+  //    for the app.
+  enum State {
+    INITIAL,
+    FETCH_LOGIN_ACCESS_TOKEN_STARTED,
+    FETCH_LOGIN_ACCESS_TOKEN_DONE,
+    MINT_ACCESS_TOKEN_STARTED,
+    MINT_ACCESS_TOKEN_DONE,
+    ERROR_STATE
+  };
+
+  enum SetupError {
+    NONE,
+    AUTH_ERROR,
+    INTERNAL_ERROR,
+    USER_CANCELLED,
+
+    // This is used for histograms, and should always be the last value.
+    SETUP_ERROR_BOUNDARY
+  };
+
+  friend class OAuth2MintTokenFlowTest;
+
+  // Creates an instance of URLFetcher that does not send or save cookies.
+  // The URLFether's method will be GET if body is empty, POST otherwise.
+  // Caller owns the returned instance.
+  content::URLFetcher* CreateURLFetcher(
+      const GURL& url, const std::string& body, const std::string& auth_token);
+  void BeginGetLoginAccessToken();
+  void EndGetLoginAccessToken(const GoogleServiceAuthError* error);
+  void BeginMintAccessToken();
+  void EndMintAccessToken(const GoogleServiceAuthError* error);
+
+  void ReportSuccess();
+  void ReportFailure(const GoogleServiceAuthError& error);
+
+  static std::string GetErrorString(SetupError error);
+
+  net::URLRequestContextGetter* context_;
+  Delegate* delegate_;
+  State state_;
+
+  std::string login_refresh_token_;
+  std::string extension_id_;
+  std::string client_id_;
+  std::vector<std::string> scopes_;
+
+  scoped_ptr<OAuth2AccessTokenFetcher> oauth2_access_token_fetcher_;
+  scoped_ptr<OAuth2MintTokenFetcher> oauth2_mint_token_fetcher_;
+  std::string login_access_token_;
+  std::string app_access_token_;
+
+  DISALLOW_COPY_AND_ASSIGN(OAuth2MintTokenFlow);
+};
+
+#endif  // CHROME_COMMON_NET_GAIA_OAUTH2_MINT_TOKEN_FLOW_H_