Hs config

MidasHistoryInterface

New history configuration defines history channels similar to logger channels. Each history channel creates a history interface class (class MidasHistoryInterface). The mlogger can use this interface to write data into the history, mhttpd, mhist & co can use this interface to read data from the history. The interface is defined in history.h

• http://ladd00.triumf.ca/~daqweb/doc/midas/include/history.h

History drivers

The MIDAS distribution contains these drivers. More drivers can be easily added by the user (create history_xxx.cxx, add constructor to hs_get_histrory(), create the ODB /Logger/History/x/channel).

• "MIDAS" is the traditional MIDAS history, data is stored in the .hst binary files. (format is documented here mhformat, see also mhist and mhdump)
• "ODBC" stores history data in SQL database using the ODBC abstraction layer. MySQL is fully supported, Pgsql support is partially implemented, support for arbitrary ODBC driver is easy to add.
• "SQLITE" stores data in SQLITE3 .sqlite3 files. The SQL table format is similar to ODBC history, performance is similar, no database server required.

ODB tree

• /Logger/
  • History/0/ --- history channel 0 (by default: "MIDAS")
    • Type --- driver type ("MIDAS")
    • Active --- y/n --- tells mlogger to write data into this channel
    • Debug --- debug level
    • PerVariableHistory --- tells mlogger to enable the Per-variable history logging mode
  • History/1/ --- history channel 1 (by default: "ODBC")
    • Type --- driver type ("ODBC")
    • Active --- y/n
    • Debug --- debug level
    • Writer_ODBC_DSN --- ODBC Data Source Name for writing (used by mlogger)
    • Reader_ODBC_DSN --- ODBC Data Source Name for reading (used by mhttpd, mhist)
  • History/2/ --- history channel 2 (by default: "SQLITE")
    • Type --- driver type ("SQLITE")
    • Active --- y/n
    • Debug --- debug level
    • Sqlite dir --- "/file/system/path" location of SQLITE database files
• /History/
  • LoggerHistoryChannel --- "0" --- default history channel for mhttpd, mhist & co

Obsoleted ODB settings:

• /Logger/WriteFileHistory (y) --- use /Logger/History/0/Active (enable/disable writing of .hst history files)
• /Logger/ODBC* --- use /Logger/History/1/Writer_ODBC_DSN
• /History/PerVariableHistory --- use /Logger/History/0/PerVariableHistory (is ODBC or SQLITE history is enable, PerVariableHistory mode is forced to "y")
• /History/ODBC* --- use /Logger/History/1/Reader_ODBC_DSN

Other ODB settings:

• /Logger/History dir --- location of "MIDAS" history data files
• /History/Events, /History/Tags, /History/DisableTags --- private data storage by "MIDAS" history. (not used by ODBC and SQLITE history)

Using the MIDAS history

AAA

Using the ODBC history

• http://ladd00.triumf.ca/~daqweb/doc/midas-old/html/F_History_logging.html

Using the SQLITE history

No special configuration required. Create a directory for storage of sqlite history files, save it's path in ODB "/Logger/History/1/Sqlite dir", set "/Logger/History/1/Active" to "y", set "/History/LoggerHistoryChannel" to "1", restart mhttpd, restart mlogger. In the history data directory you should see files with name "mh_xxx.sqlite3" corresponding to your equipment and variable names.