uima-ducc-duccdocs/src/site/tex/duccbook/part4/sm.tex

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\chapter{Service Management}
\label{chap:sm}
    The only administrative task relating to Service Management is registering
    global pingers, as described in
    \hyperref[subsec:services.pingers]{\em Service Pingers section} of this document.

    A globally-registered service pinger is a properties file that contains only
    service registraton options pertaining to pingers.  This file must be placed
    in DUCC's {\em runtime}/resources/service\_monitors directory.  It may be
    given any name but ``best practices'' would suggest it be named the
    same as the {\em service\_ping\_class}.  Services then use this pinger
    by specifying its filename in their {\em service\_ping\_class} option.
    
    Globally-registered pingers may be run internally as threads within the
    SM, or externally as processes.  To specify that a pinger be run internally,
    add the property 
\begin{verbatim}
    internal = true
\end{verbatim}
    to the registration file.  To specify that it run externall, add the property
\begin{verbatim}
    internal = false
\end{verbatim}
    to the registration file.

    The ``internal'' option is flagged as in illegal option when
    specified in service registrations and all pingers not specified as
    ``internal'' are run as {\em external} processes managed by the SM.

    Best practices dictate that the filename of an {\em external} pinger contain the
    postfix {\em .external} to clearly identify it as external.  

    As an example, the default UIMA-AS pinger is supplied in the global registery
    under the two names:
\begin{verbatim}
    org.apache.uima.ducc.cli.UimaAsPing
    org.apache.uima.ducc.cli.UimaAsPing.external
\end{verbatim}

    Note that users may override any of the properties in globally-registered
    {\em external} pingers, but only the {\em service\_ping\_arguments} of an {\em internal}
    pinger to protect its integrity by speicfy that argument in their own
    service registrations.