src/adaptation/icap/Launcher.h

   1
   2 /*
   3  * $Id$
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  15  *  incorporates software developed and/or copyrighted by other
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  19  *  it under the terms of the GNU General Public License as published by
  20  *  the Free Software Foundation; either version 2 of the License, or
  21  *  (at your option) any later version.
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  25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *  GNU General Public License for more details.
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  33
  34 #ifndef SQUID_ICAPLAUNCHER_H
  35 #define SQUID_ICAPLAUNCHER_H
  36
  37 #include "adaptation/Initiator.h"
  38 #include "adaptation/Initiate.h"
  39 #include "adaptation/icap/ServiceRep.h"
  40
  41 /*
  42  * The ICAP Launcher starts an ICAP transaction. If the transaction fails
  43  * due to what looks like a persistent connection race condition, the launcher
  44  * starts a new ICAP transaction using a freshly opened connection.
  45  *
  46  * ICAPLauncher and one or more ICAP transactions initiated by it form an
  47  * ICAP "query".
  48  *
  49  * An ICAP Initiator deals with the ICAP Launcher and not an individual ICAP
  50  * transaction because the latter may disappear and be replaced by another
  51  * transaction.
  52  *
  53  * Specific ICAP launchers implement the createXaction() method to create
  54  * REQMOD, RESPMOD, or OPTIONS transaction from initiator-supplied data.
  55  *
  56  * TODO: This class might be the right place to initiate ICAP ACL checks or
  57  * implement more sophisticated ICAP transaction handling like chaining of
  58  * ICAP transactions.
  59  */
  60
  61
  62 namespace Adaptation
  63 {
  64 namespace Icap {
  65
  66 class Xaction;
  67
  68 // Note: Initiate must be the first parent for cbdata to work. We use
  69 // a temporary InitaitorHolder/toCbdata hacks and do not call cbdata
  70 // operations on the initiator directly.
  71 class Launcher: public Adaptation::Initiate, public Adaptation::Initiator
  72 {
  73 public:
  74     Launcher(const char *aTypeName, Adaptation::Initiator *anInitiator, Adaptation::ServicePointer &aService);
  75     virtual ~Launcher();
  76
  77     // Adaptation::Initiate: asynchronous communication with the initiator
  78     void noteInitiatorAborted();
  79
  80     // Adaptation::Initiator: asynchronous communication with the current transaction
  81     virtual void noteAdaptationAnswer(HttpMsg *message);
  82     virtual void noteAdaptationQueryAbort(bool final);
  83
  84 protected:
  85     // Adaptation::Initiate API implementation
  86     virtual void start();
  87     virtual bool doneAll() const;
  88     virtual void swanSong();
  89
  90     // creates the right ICAP transaction using stored configuration params
  91     virtual Xaction *createXaction() = 0;
  92
  93     void launchXaction(bool final);
  94
  95     Adaptation::Initiate *theXaction; // current ICAP transaction
  96     int theLaunches; // the number of transaction launches
  97 };
  98
  99
 100 } // namespace Icap
 101 } // namespace Adaptation
 102
 103 #endif /* SQUID_ICAPLAUNCHER_H */