examples/ForumNokia/HTTPClientExample/inc/ClientEngine.h

/*
 * Copyright (c) 2009 Nokia Corporation.
 */

#ifndef __CLIENTENGINE_H__
#define __CLIENTENGINE_H__

#include <coecntrl.h>
#include <http\mhttpdatasupplier.h>
#include <http\mhttptransactioncallback.h>
#include <http\mhttpauthenticationcallback.h>
#include <es_sock.h>
#include <comms-infras/cs_mobility_apiext.h>
#include <cmapplicationsettingsui.h>

class RHTTPSession;
class RHTTPTransaction;

const TInt KDefaultBufferSize = 256;

/*
* MClientObserver
* CClientEngine passes events and responses body data with this interface.
* An instance of this class must be provided for construction of CClientEngine.
*/
class MClientObserver
  {
  public:
    /*
    * ClientEvent()
    *
    * Called when event occurs in CClientEngine.
    *
    * Params:
    *   aEventDescription:  A event in textual format, e.g.
    *             "Transaction Successful"
    *
    * Returns:
    *     -
    *
    */
    virtual void ClientEvent(const TDesC& aEventDescription) = 0;

    /*
    * ClientBodyReceived()
    *
    * Called when a part of the HTTP body is received.
    *
    * Params:
    *   aBodyData:  Part of the body data received. (e.g. part of
    *         the received HTML page)
    *
    * Returns:
    *     -
    *
    */
    virtual void ClientBodyReceived(const TDesC8& aBodyData) = 0;
  };

/*
* Provides simple interface to HTTP Client API.
*/
class CClientEngine : public CActive,
            public MHTTPTransactionCallback,
            public MHTTPDataSupplier,
            public MHTTPAuthenticationCallback,
            public MMobilityProtocolResp
  {
public:

    enum EngineState
        {
        EIdle = 0,
        EGet,
        EPost
        };

  /*
  * NewL()
  *
  * Create a CClientEngine object.
  *
  * Params:
  *   iObserver:
  *
  * Returns:
  *     A pointer to the created instance of CClientEngine
  *
  */
  static CClientEngine* NewL(MClientObserver& iObserver);

  /*
  * NewLC()
  *
  * Create a CClientEngine object.
  *
  * Params:
  *   iObserver:
  *
  * Returns:
  *     A pointer to the created instance of CClientEngine
  *
  */
  static CClientEngine* NewLC(MClientObserver& iObserver);

  /*
  * ~CClientEngine()
  *
  * Destroy the object
  *
  * Params:
  *   -
  *
  * Returns:
  *     -
  *
  */
  ~CClientEngine();

  /*
  * IssueHTTPGetL()
  *
  * Starts a new HTTP GET transaction.
  *
  * Params:
  *   aUri: URI to get. (e.g. http://host.org")
  *
  * Returns:
  *     -
  *
  */
  void IssueHTTPGetL(const TDesC8& aUri);

  /*
  * IssueHTTPPostL()
  *
  * Starts a new HTTP POST transaction.
  *
  * Params:
  *   aUri: URI where to post the data (e.g. http://host.org")
  *   aContentType: Content type of the body, e.g. "text/plain"
  *   aBody: Body data for the transaction.
  *
  * Returns:
  *     -
  *
  */
  void IssueHTTPPostL(const TDesC8& aUri,
            const TDesC8& aContentType,
            const TDesC8& aBody);

  /*
  * CancelTransaction()
  *
  * Closes currently running transaction and frees resources related to it.
  *
  * Params:
  *   -
  *
  * Returns:
  *     -
  *
  */
  void CancelTransaction();

  /*
  * IsRunning()
  *
  * Checks if the transaction is running.
  *
  * Params:
  *   -
  *
  * Returns:
  *     ETrue, if transaction is currently running.
  *
  */
  TBool IsRunning();

private:
  /*
  * ConstructL()
  *
  * Perform the second phase construction of a CClientEngine object.
  *
  * Params:
  *   -
  *
  * Returns:
  *     -
  *
  */
  void ConstructL();

  /*
  * CClientEngine()
  *
  * Perform the first phase of two phase construction.
  *
  * Params:
  *   iObserver:
  *
  * Returns:
  *     -
  *
  */
  CClientEngine(MClientObserver& iObserver);

  /*
  * SetHeaderL()
  *
  * Sets header value of an HTTP request.
  *
  * Params:
  *   aHeaders: Headers of the HTTP request
  *   aHdrField:  Enumerated HTTP header field, e.g. HTTP::EUserAgent
  *   aHdrValue:  New value for header field
  *
  * Returns:
  *     -
  *
  */
  void SetHeaderL(RHTTPHeaders aHeaders, TInt aHdrField,
          const TDesC8& aHdrValue);

  void SetupConnectionL();

  TBool CClientEngine::FindExistingConnection();
  
/*
* From MHTTPSessionEventCallback
*/
private:
  /*
  * MHFRunL()
  *
  * Called by framework to notify about transaction events.
  *
  * Params:
  *   aTransaction: Transaction, where the event occured.
  *   aEvent: Occured event.
  *
  * Returns:
  *     -
  *
  */
  void MHFRunL(RHTTPTransaction aTransaction, const THTTPEvent& aEvent);

  /*
  * MHFRunError()
  *
  * Called by framework when *leave* occurs in handling of transaction event.
  *
  * Params:
  *   aError:     The leave code that occured.
  *   aTransaction: The transaction that was being processed when leave
  *           occured.
  *   aEvent:     The event that was being processed when leave
  *           occured.
  *
  * Returns:
  *     KErrNone, if the error was handled. Otherwise the value of aError, or
  *   some other error value. Returning error value causes causes
  *   HTTP-CORE 6 panic.
  *
  */
  TInt MHFRunError( TInt aError,
            RHTTPTransaction aTransaction,
            const THTTPEvent& aEvent);

/*
* From MHTTPDataSupplier (needed for HTTP POST)
*/
private:
  /*
  * ReleaseData()
  *
  * Called by framework to allow data supplier to release resources
  * related to previous data part.
  *
  * Params:
  *   -
  *
  * Returns:
  *     -
  *
  */
  void ReleaseData();

  /*
  * GetNextDataPart()
  *
  * Called when next data part is needed.
  *
  * Params:
  *   aDataPart: Must be set to point to the next data part.
  *
  * Returns:
  *     ETrue if the provided data part is the last one. If more data parts
  *   are needed after the provided one, return EFalse.
  *
  */
  TBool GetNextDataPart(TPtrC8& aDataPart);

  /*
  * Reset()
  *
  * Called by framework to reset the data supplier to its initial state.
  *
  * Params:
  *   -
  *
  * Returns:
  *   KErrNone if successfull.
  *
  */
  TInt Reset();

  /*
  * OverallDataSize()
  *
  * Called by framework when it needs to know the size of the
  * body data.
  *
  * Params:
  *   -
  *
  * Returns:
  *     Size of the data, or KErrNotFound (or KErrNotSupported)
  *   if the size of the data is not known.
  *
  */
  TInt OverallDataSize();

/*
* From MHTTPAuthenticationCallback (needed for HTTP authentication)
*/
private:
  /*
  * GetCredentialsL()
  *
  * Called by framework when username and password for requested URI is
  * needed.
  *
  * Params:
  *   aURI: The URI being requested (e.g. "http://host.org")
  *   aRealm: The realm being requested (e.g. "[email protected]")
  *   aAuthenticationType: Authentication type. (e.g. "Basic")
  *   aUsername: Given user name.
  *   aPassword: Given password.
  *
  * Returns:
  *     A pointer to the created document
  *
  */
  TBool GetCredentialsL(  const TUriC8& aURI,
              RString aRealm,
              RStringF aAuthenticationType,
              RString& aUsername,
              RString& aPassword);

  
private:  // from MMobilityProtocolResp
    void PreferredCarrierAvailable(TAccessPointInfo aOldAPInfo,
                                   TAccessPointInfo aNewAPInfo,
                                   TBool aIsUpgrade,
                                   TBool aIsSeamless);
    void NewCarrierActive(TAccessPointInfo aNewAPInfo, TBool aIsSeamless);
    void Error(TInt aError);
  
private: // from CActive
    void RunL();
    void DoCancel();

private:
    void DoHTTPGetL();
    void DoHTTPPostL();    
    
private:
  // declare members
    RSocketServ                 iSocketServ;
    RConnection                 iConnection;
    TUint32                     iSelectedIap;

    RHTTPSession                iSession;
    RHTTPTransaction            iTransaction;

    MClientObserver&            iObserver;  // Used for passing body data and events to UI
    HBufC8*                     iPostData;  // Data for HTTP POST
    TBool                       iRunning;   // ETrue, if transaction running
    TBool                       iConnectionSetupDone;
    
    TInt                        iPrevProfileId;
    
    CActiveCommsMobilityApiExt* iMobility;
    TBool                       iTransactionOpen;
    EngineState                 iEngineState;
    HBufC8*                     iUri;
    HBufC8*                     iContentType;
    HBufC8*                     iBody;
    
    
  };

#endif // __CLIENTENGINE_H__

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