\section{PaWS Deployment and Management}
\label{paws_managing}

PaWS is based on the Pylons \cite{pylons} framework which is
WSGI\footnote{WSGI stands for \emph{Web Server Gateway Interface}
  \cite{wsgi} - Python specification for web servers, applications and
  web applications for communication standardization.} compliant. This
standard provides a lot of ways to deploy the WEB applications,
depending on their needs \cite{python_app_deployment}.

The easiest way is based on the \emph{Paste Script} module~\cite{paster}, which is part of Pylons and provides necessary server commands, such as:

\begin{itemize}
  \item {\bf Start the server}
  
\lstset{language=Python,caption={Starting the server},label=StartServer}
\begin{lstlisting}
. utils/pipsenv.sh
paster serve --reload development.ini
\end{lstlisting}
  
  \item {\bf Get the status of the server}
  
\lstset{language=Python,caption={Status},label=PasterStatus}
\begin{lstlisting}
paster serve --status development.ini
\end{lstlisting}
  
  \item {\bf Create the new controller}
  
\lstset{language=Python,caption={Create the new controller},label=PasterController}
\begin{lstlisting}
paster controller <controller_name>
\end{lstlisting}
  
\end{itemize}

All those commands have to be invoked in the directory, which contains
\emph{development.ini} file. See Section~\ref{structure} for detailed
information).

\subsection{Supervisor}

Currently PaWS server is run using Supervisor \cite{supervisor}, the
system for process control and monitoring. It provides a mechanism for
automatic restart of the process if it crashes.