src/adaptation/icap/Xaction.h

   1
   2 /*
   3  * $Id$
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  21  *  (at your option) any later version.
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  26  *  GNU General Public License for more details.
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  33
  34 #ifndef SQUID_ICAPXACTION_H
  35 #define SQUID_ICAPXACTION_H
  36
  37 #include "comm/forward.h"
  38 #include "CommCalls.h"
  39 #include "MemBuf.h"
  40 #include "adaptation/icap/ServiceRep.h"
  41 #include "adaptation/Initiate.h"
  42 #include "AccessLogEntry.h"
  43 #include "HttpReply.h"
  44
  45 class CommConnectCbParams;
  46
  47 namespace Adaptation
  48 {
  49 namespace Icap
  50 {
  51
  52 /*
  53  * The ICAP Xaction implements common tasks for ICAP OPTIONS, REQMOD, and
  54  * RESPMOD transactions. It is started by an Initiator. It terminates
  55  * on its own, when done. Transactions communicate with Initiator using
  56  * asynchronous messages because a transaction or Initiator may be gone at
  57  * any time.
  58  */
  59
  60 // Note: Xaction must be the first parent for object-unaware cbdata to work
  61
  62 class Xaction: public Adaptation::Initiate
  63 {
  64
  65 public:
  66     Xaction(const char *aTypeName, ServiceRep::Pointer &aService);
  67     virtual ~Xaction();
  68
  69     void disableRetries();
  70     void disableRepeats(const char *reason);
  71     bool retriable() const { return isRetriable; }
  72     bool repeatable() const { return isRepeatable; }
  73
  74     // comm handler wrappers, treat as private
  75     void noteCommConnected(const CommConnectCbParams &io);
  76     void noteCommWrote(const CommIoCbParams &io);
  77     void noteCommRead(const CommIoCbParams &io);
  78     void noteCommTimedout(const CommTimeoutCbParams &io);
  79     void noteCommClosed(const CommCloseCbParams &io);
  80
  81     // TODO: create these only when actually sending/receiving
  82     HttpRequest *icapRequest; ///< sent (or at least created) ICAP request
  83     HttpReply::Pointer icapReply; ///< received ICAP reply, if any
  84
  85     /// the number of times we tried to get to the service, including this time
  86     int attempts;
  87
  88 protected:
  89     virtual void start();
  90     virtual void noteInitiatorAborted(); // TODO: move to Adaptation::Initiate
  91
  92     // comm hanndlers; called by comm handler wrappers
  93     virtual void handleCommConnected() = 0;
  94     virtual void handleCommWrote(size_t sz) = 0;
  95     virtual void handleCommRead(size_t sz) = 0;
  96     virtual void handleCommTimedout();
  97     virtual void handleCommClosed();
  98
  99     void openConnection();
 100     void closeConnection();
 101     void dieOnConnectionFailure();
 102     bool haveConnection() const;
 103
 104     void scheduleRead();
 105     void scheduleWrite(MemBuf &buf);
 106     void updateTimeout();
 107
 108     void cancelRead();
 109
 110     bool parseHttpMsg(HttpMsg *msg); // true=success; false=needMore; throw=err
 111     bool mayReadMore() const;
 112
 113     virtual bool doneReading() const;
 114     virtual bool doneWriting() const;
 115     bool doneWithIo() const;
 116     virtual bool doneAll() const;
 117
 118     // called just before the 'done' transaction is deleted
 119     virtual void swanSong();
 120
 121     // returns a temporary string depicting transaction status, for debugging
 122     virtual const char *status() const;
 123     virtual void fillPendingStatus(MemBuf &buf) const;
 124     virtual void fillDoneStatus(MemBuf &buf) const;
 125
 126     // useful for debugging
 127     virtual bool fillVirginHttpHeader(MemBuf&) const;
 128
 129 public:
 130     // custom exception handling and end-of-call checks
 131     virtual void callException(const std::exception  &e);
 132     virtual void callEnd();
 133
 134 protected:
 135     // logging
 136     void setOutcome(const XactOutcome &xo);
 137     virtual void finalizeLogInfo();
 138
 139     ServiceRep &service();
 140
 141 private:
 142     void tellQueryAborted();
 143     void maybeLog();
 144
 145 protected:
 146     Comm::ConnectionPointer connection;     ///< ICAP server connection
 147     Adaptation::Icap::ServiceRep::Pointer theService;
 148
 149     /*
 150      * We have two read buffers.   We would prefer to read directly
 151      * into the MemBuf, but since comm_read isn't MemBuf-aware, and
 152      * uses event-delayed callbacks, it leaves the MemBuf in an
 153      * inconsistent state.  There would be data in the buffer, but
 154      * MemBuf.size won't be updated until the (delayed) callback
 155      * occurs.   To avoid that situation we use a plain buffer
 156      * (commBuf) and then copy (append) its contents to readBuf in
 157      * the callback.  If comm_read ever becomes MemBuf-aware, we
 158      * can eliminate commBuf and this extra buffer copy.
 159      */
 160     MemBuf readBuf;
 161     char *commBuf;
 162     size_t commBufSize;
 163     bool commEof;
 164     bool reuseConnection;
 165     bool isRetriable;  ///< can retry on persistent connection failures
 166     bool isRepeatable; ///< can repeat if no or unsatisfactory response
 167     bool ignoreLastWrite;
 168
 169     const char *stopReason;
 170
 171     // active (pending) comm callbacks for the ICAP server connection
 172     AsyncCall::Pointer connector;
 173     AsyncCall::Pointer reader;
 174     AsyncCall::Pointer writer;
 175     AsyncCall::Pointer closer;
 176
 177     AccessLogEntry al;
 178
 179     timeval icap_tr_start;     /*time when the ICAP transaction was created */
 180     timeval icap_tio_start;    /*time when the first ICAP request byte was scheduled for sending*/
 181     timeval icap_tio_finish;   /*time when the last byte of the ICAP responsewas received*/
 182
 183 private:
 184     //CBDATA_CLASS2(Xaction);
 185 };
 186
 187
 188 } // namespace Icap
 189 } // namespace Adaptation
 190
 191 #endif /* SQUID_ICAPXACTION_H */