Android中CookieManager的底层实现

 

                  前几天，项目组有个技术问题，想用本地加载html， js写cookie的方法，绕过去。

                  想法是没有问题的， 但是测试的时候发现， 每次重新打开App， 都取不到以前Cookie里面设的值。

                 后来去App/data下面找WebView.db，打开来一看，cookie情报根本没有存。

                 原因是js写cookie的时候，没有指明expire, WebKit默认把它当成临时cookie， webview终了之后就丢失了。

                 这个问题本身不复杂，不过趁机我看了一把Andorid底层读取Cookie的source root:

 

以下source root

 

  1. 取Cookie的API

                 

CookieManager.getInstance().getCookie(url);

CookieManager.getInstance().getCookie(url);

 

2.CookieManager的getInstance()

 

/**
    * Gets the singleton CookieManager instance. If this method is used
    * before the application instantiates a {@link WebView} instance,
    * {@link CookieSyncManager#createInstance(Context)} must be called
    * first.
    *
    * @return the singleton CookieManager instance
    */
   publicstaticsynchronized CookieManager getInstance() {
       return WebViewFactory.getProvider().getCookieManager();
   }

 /**

     * Gets the singleton CookieManager instance. If this method is used

     * before the application instantiates a {@link WebView} instance,

     * {@link CookieSyncManager#createInstance(Context)} must be called

     * first.

     *

     * @return the singleton CookieManager instance

     */

    public static synchronized CookieManager getInstance() {

        return WebViewFactory.getProvider().getCookieManager();

    }

3.WebViewFactory是个工厂模式，额

 

 

staticsynchronized WebViewFactoryProvider getProvider() {
    // For now the main purpose of this function (and the factory abstraction) is to keep
    // us honest and minimize usage of WebViewClassic internals when binding the proxy.
    if (sProviderInstance != null) return sProviderInstance;

    sProviderInstance = getFactoryByName(DEFAULT_WEB_VIEW_FACTORY);
    if (sProviderInstance == null) {
        if (DEBUG) Log.v(LOGTAG, "Falling back to explicit linkage");
        sProviderInstance = new WebViewClassic.Factory();
    }
    return sProviderInstance;
}

    static synchronized WebViewFactoryProvider getProvider() {

        // For now the main purpose of this function (and the factory abstraction) is to keep

        // us honest and minimize usage of WebViewClassic internals when binding the proxy.

        if (sProviderInstance != null) return sProviderInstance;



        sProviderInstance = getFactoryByName(DEFAULT_WEB_VIEW_FACTORY);

        if (sProviderInstance == null) {

            if (DEBUG) Log.v(LOGTAG, "Falling back to explicit linkage");

            sProviderInstance = new WebViewClassic.Factory();

        }

        return sProviderInstance;

    }

4.层层嵌套，最后生成的instance是CookieManagerClassic

 

 

@Override
       public CookieManager getCookieManager() {
           return CookieManagerClassic.getInstance();
       }

 @Override

        public CookieManager getCookieManager() {

            return CookieManagerClassic.getInstance();

        }

5. getCookie方法 实现在CookieManagerClassic上

 

 

@Override
  public String getCookie(String url) {
      return getCookie(url, false);
  }

  @Override
  public String getCookie(String url, boolean privateBrowsing) {
      WebAddress uri;
      try {
          uri = new WebAddress(url);
      } catch (ParseException ex) {
          Log.e(LOGTAG, "Bad address: " + url);
          returnnull;
      }

      return nativeGetCookie(uri.toString(), privateBrowsing);
  }

  @Override

    public String getCookie(String url) {

        return getCookie(url, false);

    }



    @Override

    public String getCookie(String url, boolean privateBrowsing) {

        WebAddress uri;

        try {

            uri = new WebAddress(url);

        } catch (ParseException ex) {

            Log.e(LOGTAG, "Bad address: " + url);

            return null;

        }



        return nativeGetCookie(uri.toString(), privateBrowsing);

    }

6. nativeGetCookie定义在CookieManager.cpp里， 恩。。。。JNI。。。

 

 

static jstring getCookie(JNIEnv* env, jobject, jstring url, jboolean privateBrowsing)
{
    GURL gurl(jstringToStdString(env, url));
    CookieOptions options;
    options.set_include_httponly();
    std::string cookies = WebCookieJar::get(privateBrowsing)->cookieStore()->GetCookieMonster()->GetCookiesWithOptions(gurl, options);
    return stdStringToJstring(env, cookies);
}

static jstring getCookie(JNIEnv* env, jobject, jstring url, jboolean privateBrowsing)

{

    GURL gurl(jstringToStdString(env, url));

    CookieOptions options;

    options.set_include_httponly();

    std::string cookies = WebCookieJar::get(privateBrowsing)->cookieStore()->GetCookieMonster()->GetCookiesWithOptions(gurl, options);

    return stdStringToJstring(env, cookies);

}

7. WebCookieJar.cpp中，定义了从哪里去取得Cookie情报

 

 

WebCookieJar* WebCookieJar::get(bool isPrivateBrowsing)
{
    MutexLocker lock(instanceMutex);
    if (!isFirstInstanceCreated && fileSchemeCookiesEnabled)
        net::CookieMonster::EnableFileScheme();
    isFirstInstanceCreated = true;
    scoped_refptr<WebCookieJar>* instancePtr = instance(isPrivateBrowsing);
    if (!instancePtr->get())
        *instancePtr = new WebCookieJar(databaseDirectory(isPrivateBrowsing));
    return instancePtr->get();
}

WebCookieJar* WebCookieJar::get(bool isPrivateBrowsing)

{

    MutexLocker lock(instanceMutex);

    if (!isFirstInstanceCreated && fileSchemeCookiesEnabled)

        net::CookieMonster::EnableFileScheme();

    isFirstInstanceCreated = true;

    scoped_refptr<WebCookieJar>* instancePtr = instance(isPrivateBrowsing);

    if (!instancePtr->get())

        *instancePtr = new WebCookieJar(databaseDirectory(isPrivateBrowsing));

    return instancePtr->get();

}

static std::string databaseDirectory(bool isPrivateBrowsing)
{
    staticconstchar* const kDatabaseFilename = "/webviewCookiesChromium.db";
    staticconstchar* const kDatabaseFilenamePrivateBrowsing = "/webviewCookiesChromiumPrivate.db";

    std::string databaseFilePath = databaseDirectory();
    databaseFilePath.append(isPrivateBrowsing ? kDatabaseFilenamePrivateBrowsing : kDatabaseFilename);
    return databaseFilePath;
}

static std::string databaseDirectory(bool isPrivateBrowsing)

{

    static const char* const kDatabaseFilename = "/webviewCookiesChromium.db";

    static const char* const kDatabaseFilenamePrivateBrowsing = "/webviewCookiesChromiumPrivate.db";



    std::string databaseFilePath = databaseDirectory();

    databaseFilePath.append(isPrivateBrowsing ? kDatabaseFilenamePrivateBrowsing : kDatabaseFilename);

    return databaseFilePath;

}

※Android3.0以上是webviewCookiesChromium.db, 以下是WebView.db文件

 

 

8.最后读取Cookie情报发生在cookie_monster.cc。 额，最后调到C++， 去读.db文件，无敌了

 

std::string CookieMonster::GetCookiesWithOptions(const GURL& url,
                                                 const CookieOptions& options) {
  base::AutoLock autolock(lock_);
  InitIfNecessary();

  if (!HasCookieableScheme(url)) {
    return std::string();
  }

  TimeTicks start_time(TimeTicks::Now());

  // Get the cookies for this host and its domain(s).
  std::vector<CanonicalCookie*> cookies;
  FindCookiesForHostAndDomain(url, options, true, &cookies);
  std::sort(cookies.begin(), cookies.end(), CookieSorter);

  std::string cookie_line;
  for (std::vector<CanonicalCookie*>::const_iterator it = cookies.begin();
       it != cookies.end(); ++it) {
    if (it != cookies.begin())
      cookie_line += "; ";
    // In Mozilla if you set a cookie like AAAA, it will have an empty token
    // and a value of AAAA.  When it sends the cookie back, it will send AAAA,
    // so we need to avoid sending =AAAA for a blank token value.
    if (!(*it)->Name().empty())
      cookie_line += (*it)->Name() + "=";
    cookie_line += (*it)->Value();
  }

  histogram_time_get_->AddTime(TimeTicks::Now() - start_time);

  VLOG(kVlogGetCookies) << "GetCookies() result: " << cookie_line;

  return cookie_line;
}

std::string CookieMonster::GetCookiesWithOptions(const GURL& url,

                                                 const CookieOptions& options) {

  base::AutoLock autolock(lock_);

  InitIfNecessary();



  if (!HasCookieableScheme(url)) {

    return std::string();

  }



  TimeTicks start_time(TimeTicks::Now());



  // Get the cookies for this host and its domain(s).

  std::vector<CanonicalCookie*> cookies;

  FindCookiesForHostAndDomain(url, options, true, &cookies);

  std::sort(cookies.begin(), cookies.end(), CookieSorter);



  std::string cookie_line;

  for (std::vector<CanonicalCookie*>::const_iterator it = cookies.begin();

       it != cookies.end(); ++it) {

    if (it != cookies.begin())

      cookie_line += "; ";

    // In Mozilla if you set a cookie like AAAA, it will have an empty token

    // and a value of AAAA.  When it sends the cookie back, it will send AAAA,

    // so we need to avoid sending =AAAA for a blank token value.

    if (!(*it)->Name().empty())

      cookie_line += (*it)->Name() + "=";

    cookie_line += (*it)->Value();

  }



  histogram_time_get_->AddTime(TimeTicks::Now() - start_time);



  VLOG(kVlogGetCookies) << "GetCookies() result: " << cookie_line;



  return cookie_line;

}

#以上#