src/adaptation/icap/Xaction.h

   1
   2 /*
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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.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
  44 class HttpMsg;
  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 *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
 103     void scheduleRead();
 104     void scheduleWrite(MemBuf &buf);
 105     void updateTimeout();
 106
 107     void cancelRead();
 108
 109     bool parseHttpMsg(HttpMsg *msg); // true=success; false=needMore; throw=err
 110     bool mayReadMore() const;
 111
 112     virtual bool doneReading() const;
 113     virtual bool doneWriting() const;
 114     bool doneWithIo() const;
 115     virtual bool doneAll() const;
 116
 117     // called just before the 'done' transaction is deleted
 118     virtual void swanSong();
 119
 120     // returns a temporary string depicting transaction status, for debugging
 121     virtual const char *status() const;
 122     virtual void fillPendingStatus(MemBuf &buf) const;
 123     virtual void fillDoneStatus(MemBuf &buf) const;
 124
 125     // useful for debugging
 126     virtual bool fillVirginHttpHeader(MemBuf&) const;
 127
 128 public:
 129     // custom exception handling and end-of-call checks
 130     virtual void callException(const std::exception  &e);
 131     virtual void callEnd();
 132
 133 protected:
 134     // logging
 135     void setOutcome(const XactOutcome &xo);
 136     virtual void finalizeLogInfo();
 137
 138     ServiceRep &service();
 139
 140 private:
 141     void tellQueryAborted();
 142     void maybeLog();
 143
 144 protected:
 145     int connection;     // FD of the ICAP server connection
 146     Adaptation::Icap::ServiceRep::Pointer theService;
 147
 148     /*
 149      * We have two read buffers.   We would prefer to read directly
 150      * into the MemBuf, but since comm_read isn't MemBuf-aware, and
 151      * uses event-delayed callbacks, it leaves the MemBuf in an
 152      * inconsistent state.  There would be data in the buffer, but
 153      * MemBuf.size won't be updated until the (delayed) callback
 154      * occurs.   To avoid that situation we use a plain buffer
 155      * (commBuf) and then copy (append) its contents to readBuf in
 156      * the callback.  If comm_read ever becomes MemBuf-aware, we
 157      * can eliminate commBuf and this extra buffer copy.
 158      */
 159     MemBuf readBuf;
 160     char *commBuf;
 161     size_t commBufSize;
 162     bool commEof;
 163     bool reuseConnection;
 164     bool isRetriable;  ///< can retry on persistent connection failures
 165     bool isRepeatable; ///< can repeat if no or unsatisfactory response
 166     bool ignoreLastWrite;
 167
 168     const char *stopReason;
 169
 170     // active (pending) comm callbacks for the ICAP server connection
 171     AsyncCall::Pointer connector;
 172     AsyncCall::Pointer reader;
 173     AsyncCall::Pointer writer;
 174     AsyncCall::Pointer closer;
 175
 176     AccessLogEntry al;
 177
 178     timeval icap_tr_start;     /*time when the ICAP transaction was created */
 179     timeval icap_tio_start;    /*time when the first ICAP request byte was scheduled for sending*/
 180     timeval icap_tio_finish;   /*time when the last byte of the ICAP responsewas received*/
 181
 182 private:
 183     //CBDATA_CLASS2(Xaction);
 184 };
 185
 186
 187 } // namespace Icap
 188 } // namespace Adaptation
 189
 190 #endif /* SQUID_ICAPXACTION_H */