src/mgr/Inquirer.h

   1 /*
   2  * $Id$
   3  *
   4  * DEBUG: section 16    Cache Manager API
   5  *
   6  */
   7
   8 #ifndef SQUID_MGR_INQUIRER_H
   9 #define SQUID_MGR_INQUIRER_H
  10
  11 #include "base/AsyncJobCalls.h"
  12 #include "base/AsyncJob.h"
  13 #include "ipc/StrandCoords.h"
  14 #include "MemBuf.h"
  15 #include "mgr/Action.h"
  16 #include "mgr/Request.h"
  17 #include <map>
  18
  19 class CommIoCbParams;
  20 class CommCloseCbParams;
  21
  22 namespace Mgr
  23 {
  24
  25 /// Coordinator's job that sends a cache manage request to each strand,
  26 /// aggregating individual strand responses and dumping the result if needed
  27 class Inquirer: public AsyncJob
  28 {
  29 public:
  30     Inquirer(Action::Pointer anAction, int aFd, const Request &aCause,
  31              const Ipc::StrandCoords &coords);
  32     virtual ~Inquirer();
  33
  34     /// finds and calls the right Inquirer upon strand's response
  35     static void HandleRemoteAck(const Mgr::Response& response);
  36
  37 protected:
  38     /* AsyncJob API */
  39     virtual void start();
  40     virtual void swanSong();
  41     virtual bool doneAll() const;
  42     virtual const char *status() const;
  43
  44 private:
  45     typedef UnaryMemFunT<Inquirer, Response, const Response&> HandleAckDialer;
  46
  47     void inquire();
  48     void noteWroteHeader(const CommIoCbParams& params);
  49     void noteCommClosed(const CommCloseCbParams& params);
  50
  51     void handleRemoteAck(const Response& response);
  52
  53     static AsyncCall::Pointer DequeueRequest(unsigned int requestId);
  54
  55     static void RequestTimedOut(void* param);
  56     void requestTimedOut();
  57     void removeTimeoutEvent();
  58
  59     void close();
  60     void removeCloseHandler();
  61     Ipc::StrandCoords applyQueryParams(const Ipc::StrandCoords& aStrands,
  62                                        const QueryParams& aParams);
  63
  64 private:
  65     Action::Pointer aggrAction; //< action to aggregate
  66
  67     Request cause; ///< cache manager request received from HTTP client
  68     int fd; ///< HTTP client socket descriptor
  69
  70     Ipc::StrandCoords strands; ///< all strands we want to query, in order
  71     Ipc::StrandCoords::const_iterator pos; ///< strand we should query now
  72
  73     unsigned int requestId; ///< ID of our outstanding request to strand
  74     AsyncCall::Pointer writer; ///< comm_write callback
  75     AsyncCall::Pointer closer; ///< comm_close handler
  76     const double timeout; ///< number of seconds to wait for strand response
  77
  78     /// maps requestId to Inquirer::handleRemoteAck callback
  79     typedef std::map<unsigned int, AsyncCall::Pointer> RequestsMap;
  80     static RequestsMap TheRequestsMap; ///< pending strand requests
  81
  82     static unsigned int LastRequestId; ///< last requestId used
  83
  84     CBDATA_CLASS2(Inquirer);
  85 };
  86
  87 } // namespace Mgr
  88
  89 #endif /* SQUID_MGR_INQUIRER_H */