src/adaptation/History.h

   1 #ifndef SQUID_ADAPT_HISTORY_H
   2 #define SQUID_ADAPT_HISTORY_H
   3
   4 #include "adaptation/DynamicGroupCfg.h"
   5 #include "Array.h"
   6 #include "HttpHeader.h"
   7 #include "RefCount.h"
   8 #include "SquidString.h"
   9
  10 namespace Adaptation
  11 {
  12
  13 /// collects information about adaptations related to a master transaction
  14 class History: public RefCountable
  15 {
  16 public:
  17     typedef RefCount<Adaptation::History> Pointer;
  18
  19     History();
  20
  21     /// record the start of a xact, return xact history ID
  22     int recordXactStart(const String &serviceId, const timeval &when, bool retrying);
  23
  24     /// record the end of a xact identified by its history ID
  25     void recordXactFinish(int hid);
  26
  27     /// dump individual xaction times to a string
  28     void allLogString(const char *serviceId, String &buf);
  29
  30     /// dump xaction times, merging retried and retry times together
  31     void sumLogString(const char *serviceId, String &buf);
  32
  33     /// sets or resets a cross-transactional database record
  34     void updateXxRecord(const char *name, const String &value);
  35
  36     /// returns true and fills the record fields iff there is a db record
  37     bool getXxRecord(String &name, String &value) const;
  38
  39     /// sets or resets next services for the Adaptation::Iterator to notice
  40     void updateNextServices(const String &services);
  41
  42     /// returns true, fills the value, and resets iff next services were set
  43     bool extractNextServices(String &value);
  44
  45     /// store the last meta header fields received from the adaptation service
  46     void recordMeta(const HttpHeader *lm);
  47
  48 public:
  49     /// Last received meta header (REQMOD or RESPMOD, whichever comes last).
  50     HttpHeader lastMeta;
  51     /// All REQMOD and RESPMOD meta headers merged. Last field wins conflicts.
  52     HttpHeader allMeta;
  53
  54     /// sets future services for the Adaptation::AccessCheck to notice
  55     void setFutureServices(const DynamicGroupCfg &services);
  56
  57     /// returns true, fills the value, and resets iff future services were set
  58     bool extractFutureServices(DynamicGroupCfg &services);
  59
  60 private:
  61     /// single Xaction stats (i.e., a historical record entry)
  62     class Entry
  63     {
  64     public:
  65         Entry(const String &serviceId, const timeval &when);
  66         Entry(); // required by Vector<>
  67
  68         void stop(); ///< updates stats on transaction end
  69         int rptm(); ///< returns response time [msec], calculates it if needed
  70
  71         String service; ///< adaptation service ID
  72         timeval start; ///< when the xaction was started
  73
  74     private:
  75         int theRptm; ///< calculated and cached response time value in msec
  76
  77     public:
  78         bool retried; ///< whether the xaction was replaced by another
  79     };
  80
  81     typedef Vector<Entry> Entries;
  82     Entries theEntries; ///< historical record, in the order of xact starts
  83
  84     // theXx* will become a map<string,string>, but we only support one record
  85     String theXxName; ///< name part of the cross-transactional database record
  86     String theXxValue; ///< value part of the cross-xactional database record
  87
  88     String theNextServices; ///< services Adaptation::Iterator must use next
  89     DynamicGroupCfg theFutureServices; ///< services AccessCheck must use
  90 };
  91
  92 } // namespace Adaptation
  93
  94 #endif