PagingServer 15.8.67

Start/run in the foreground

Aka simple non-forking start.

Just run the thing as:

% paging

Can be used directly from terminal, or with any init system or daemon manager, including systemd, upstart, openrc, runit, daemontools, debian’s “start-stop-daemon”, simple bash scripts, etc.

For systemd in particular, see the “Running as a systemd service” section below.

Running from terminal to understand what’s going on, these options might be also useful:

% paging --debug
% paging --debug --pjsua-log-level 10
% paging --dump-conf

See also “Installation” and “Audio configuration” sections below.

Running as a systemd service

This method should be preferred, as it correctly notifies init when service is actually ready (i.e. pjsua inputs/outputs initialized), so that others can be scheduled around that, and primes watchdog timer, detecting if/when app might hang due to some bug.

Provided paging.service file (in the repository, just an ini file) should be installed to /etc/systemd/system, and assumes following things:

• PagingServer app should be run as a “paging” user, which exists on the system (e.g. in /etc/passwd).

• “paging.py” script, its “entry point” or symlink to it is installed at /usr/local/bin/paging.

• Configuration file can be read from one of default paths (see above for a list of these).

• Optional python-systemd module dependency is installed.

With all these correct, service can then be used like this:

• Start/stop/restart service:

  % systemctl start paging
  % systemctl stop paging
  % systemctl restart paging

• Enable service to start on OS boot: systemctl enable paging

• See if service is running, show last log entries: systemctl status paging

• Show all logging for service since last OS boot: journalctl -ab -u paging

• Brutally kill service if it hangs on stop/restart: systemctl kill -s KILL paging (will be done after ~60s by systemd automatically).

See systemctl(1) manpage for more info on such commands.

If either app itself is installed to another location (not /usr/local/bin/paging) or extra command-line parameters for it are required, ExecStart= line can be altered either in installed systemd unit file directly, or via systemctl edit paging.

systemctl daemon-reload should be run for any modifications to /etc/systemd/system/paging.service to take effect.

Similarly, User=paging line can be altered or overidden to change system uid to use for the app.

If python-systemd module is unavailable, following lines should be dropped from the paging.service:

Type=notify
WatchdogSec=...

And --systemd option removed from ExecStart= line, so that app would be started as a simple non-forking process, which will then be treated correctly by systemd without two options above.

Requirements

• Python 2.7 (NOT 3.X).

• PJSUA (PJSIP User Agent) and its python bindings.

  Can be packaged as “pjsip”, “pjsua” or “pjproject” in linux distros.

  Python bindings (from the same tarball) can also be packaged separately as “python-pjproject” or something like that.

  If either of those isn’t available, be sure to build and install pjsua AND its python bindings manually from the same sources, and NOT e.g. install pjsua from package and then build bindings separately.

• JACK - both JACK1 (C) and JACK2 (C++) forks should work.

  Only tested with JACK1 fork, but as both have same ABI and only interacted with via libjack, there should be no difference wrt which one is actually running.

• JACK-Client python module

• (optional) ffmpeg binary - if audio samples are not wav files (will be converted on every startup, if needed).

• (optional) python-systemd - only if --systemd option is used (e.g. with shipped .service file).

  Developed and shipped separately from main systemd package since v223 (2015-07-29), likely comes installed with systemd prior to that.

  Would probably make sense to install that module from OS package, which should be available if systemd is used there as init by default.

• (optional) raven python module - for reporting any errors via sentry.

Step-by-step installation process

It’s recommended to follow these in roughly same order, as next ones might rely on stuff installed in the previous ones.

Each step can be skipped entirely if “Verify or check” commands for it work, when packages in question were installed through some other means. But be sure to run at least those commands to spot any potential issues.

Line prefixed by “%” are meant to be executed in the terminal with that prefix removed.

• Install generic build tools and python dev packages.

  Debian / Ubuntu:

  % apt-get install python python-pip python-virtualenv

  Arch Linux:

  % pacman -S python2 python2-pip python2-virtualenv

  Verify or check if already installed:

  % pip --version
  pip 1.5.6 from /usr/lib/python2.7/dist-packages (python 2.7)
  
  % virtualenv --version
  1.11.6

  Note that on some systems, “pip” for python-2.7 might be installed as “pip2” or “pip-2.7”, same might apply to “virtualenv”, substitute these as necessary.

• Install JACK sound server.

  JACK is very mature and widely-used project, hence is packaged for all major linux distros, hence it’s better to install it using distro’s package manager.

  There are two different forks of JACK, both are in use and maintained - JACK1 (C) and JACK2 (C++).

  It is recommended to install JACK1 (or simply “jack”, not e.g. “jack2”) package, as this script is tested to work with that fork, but “jack2” should likely work just as well.

  • Debian/Ubuntu:

    apt-get install --no-install-recommends jackd1

    Note the --no-install-recommends flag, which should prevent Debian from installing “recommended” GUI packages and X11 server for these. None of them are needed or helpful, hence that option here.

    “Realtime process priority” option (which apt-get might ask) is irrelevant.

  • Arch Linux: pacman -S jack

  • Other distros: install from distro repositories (recommended) or build it (JACK1) from sources available at http://jackaudio.org/downloads/

  Verify or check if already installed:

  % jackd --version
  jackd version 0.124.1 tmpdir /dev/shm protocol 25

  Here versions 0.X (such as in example above) will indicate that JACK1 is installed and versions 1.X for JACK2.

• Build/install PJSIP project and its python bindings.

  If PJSIP (can also be called: pj, pjsip, pjproject, pjsua) packaged for your distro (e.g. pjproject packages for Debian Sid, or in AUR on Arch), it might be easier to install these and avoid building them from scratch entirely.

  See also all the great PJSIP build/installation instructions:

  http://trac.pjsip.org/repos/wiki/Getting-Started

  http://trac.pjsip.org/repos/wiki/Getting-Started/Download-Source

  http://trac.pjsip.org/repos/wiki/Getting-Started/Build-Preparation

  http://trac.pjsip.org/repos/wiki/Getting-Started/Autoconf

  Below in this step is just a shorter version of these.

  Some operations below, such as obvious package manager invocations, and where otherwise noted, should be run as “root”, or can be prefixed with “sudo”, if necessary.

  Install build-tools and python headers:

  • Debian: apt-get install build-essential python-dev libjack-dev

  • Arch: pacman -S base-devel

  On source-based distros like Gentoo, gcc, headers and such are always come pre-installed, so neither “build tools” nor “dev”-type extra packages are necessary.

  Verify or check if tools/headers are already installed:

  % cc --version
  cc (Debian 4.9.2-10) 4.9.2
  
  % make --version
  GNU Make 4.0
  
  % python2-config --includes
  -I/usr/include/python2.7 -I/usr/include/x86_64-linux-gnu/python2.7

  Get the latest release of PJSIP code from http://www.pjsip.org/download.htm with one of these commands (substituting newer release URL, if possible):

  % wget http://www.pjsip.org/release/2.4.5/pjproject-2.4.5.tar.bz2 && tar xf pjproject-2.4.5.tar.bz2
  ### or
  % curl http://www.pjsip.org/release/2.4.5/pjproject-2.4.5.tar.bz2 | tar xj
  ### or (NOT RECOMMENDED, can be too buggy)
  % svn export http://svn.pjsip.org/repos/pjproject/trunk pjproject

  Build the code:

  % cd pjproject*
  % ./configure --prefix=/usr --enable-shared --disable-v4l2 --disable-video
  
  % sed -i 's/\(AC_PA_USE_.*\)=1/\1=0/' third_party/build/portaudio/os-auto.mak
  % echo 'AC_PA_USE_JACK=1' >>third_party/build/portaudio/os-auto.mak
  % echo 'export CFLAGS += -DPA_USE_JACK=1' >>third_party/build/portaudio/os-auto.mak
  % echo 'PORTAUDIO_OBJS += pa_jack.o pa_ringbuffer.o' >>third_party/build/portaudio/os-auto.mak
  % echo '#include "../../../portaudio/src/hostapi/jack/pa_jack.c"' > third_party/build/portaudio/src/pa_jack.c
  % echo '#include "../../../portaudio/include/pa_jack.h"' > third_party/build/portaudio/src/pa_jack.h
  % sed -i 's/-lportaudio/-ljack \0/' build.mak
  
  % make dep
  % make

  Above alterations (sed and echo lines) are necessary to enable JACK support in PortAudio version bundled with pjsip.

  Instead of that patching (e.g. if it fails for some future pjsip versions), it is possible to install portaudio with JACK support from OS repositories and add --with-external-pa option to ./configure ... line, but is not recommended here.

  Install pjsip/pjsua libs (should be done as root or via sudo):

  • On Debian/Ubuntu (or similar distros):

    % apt-get install checkinstall
    % sed -i 's/^\(\s\+\)cp -af /\1cp -r /' Makefile
    % checkinstall -y
    
    ...
    **********************************************************************
     Done. The new package has been installed and saved to
     /root/pjproject-2.4.5/pjproject_2.4.5-1_amd64.deb
     You can remove it from your system anytime using: dpkg -r pjproject
    **********************************************************************
    
    % dpkg -s pjproject
    
    ...
    Status: install ok installed
    ...

    This will create (via “checkinstall” tool) and cleanly install .deb package to the system, making it easy to remove/update it later.

    If “checkinstall” isn’t your cup of tea, more generic way below should work as well.

  • On any random linux/unix distro:

    % make install

    Easy, but there’s almost always a better way, that makes packaging system aware of (and hence capable of managing) the installed files.

  Install python pjsua bindings (should be done as root or via sudo):

  • On Debian/Ubuntu (or similar distros):

    % pushd pjsip-apps/src/python
    % checkinstall -y --pkgname=python-pjsua python2 setup.py install
    % popd

    Same as above, using “checkinstall” is highly recommended on these distros.

  • On any generic linux (or similar system):

    % pushd pjsip-apps/src/python
    % python2 setup.py install
    % popd

    ... install --user can be used to install package for current user only, or whole step can be performed with virtualenv active to install it there.

  Note that pjsua bindings are just a regular python package, and hence subject to any general python package installation/management guidelines, e.g. aforementioned python packaging tutorial.

  Verify or check if pjsip/pjproject/pjsua are all installed and can be used from python:

  % python2 -c 'import pjsua; lib = pjsua.Lib(); lib.init(); lib.destroy()'
  
  04:43:41.097 os_core_unix.c !pjlib 2.4.5 for POSIX initialized
  04:43:41.097 sip_endpoint.c  .Creating endpoint instance...
  04:43:41.097          pjlib  .select() I/O Queue created (0x230f630)
  04:43:41.097 sip_endpoint.c  .Module "mod-msg-print" registered
  04:43:41.097 sip_transport.  .Transport manager created.
  04:43:41.098   pjsua_core.c  .PJSUA state changed: NULL --> CREATED

  Last command should not give anything like “ImportError” or segmentation faults, and should exit cleanly with output similar to one presented above.

• Prepare environment for PagingServer, install it and its python dependency modules.

  It’d be unwise to run this app as a “root” user, so special uid should be created for it (from a root user), along with home directory, where all app files will reside:

  % useradd -d /srv/paging -s /bin/bash paging
  % mkdir -p -m700 ~paging
  % chown -R paging: ~paging

  “User=paging” is also used in systemd unit (installed and explained below), so if other user name will be used here, it should be changed there as well.

  Same goes for directory used here.

  Then, for all the next commands in this step, shell should be switched to the created user, which can be done by running “su” with root privileges:

  % su - paging
  
  % id
  uid=1001(paging) gid=1001(paging) groups=1001(paging)

  This should likely also change the shell prompt, and “id” command should give non-root uid/gid (as shown above).

  IMPORTANT: DO NOT skip any errors from su - paging command above before running the next steps.

  Create python virtualenv for installing the app there:

  % virtualenv --clear --system-site-packages --python=python2.7 PagingServer
  % cd PagingServer
  % . bin/activate
  
  % python2 -c 'import sys; print sys.path[1]'
  /srv/paging/PagingServer/lib/python2.7

  Last command can be used to verify that sys.path[1] indeed points to a subdir in ~paging, and not something in /usr, which means that virtualenv was correctly activated for this shell session.

  Install the app and all its python module dependencies:

  % pip install PagingServer
  
  Downloading/unpacking PagingServer
  ...
  Downloading/unpacking JACK-Client (from PagingServer)
  ...
  Successfully installed PagingServer
  Cleaning up...

  Make sure app is installed and works with installed pjsua version:

  % paging --version
  paging version-unknown (see python package version)
  
  % paging --dump-pjsua-conf-ports
  Detected conference ports:
  ...
  
  % paging --dump-pjsua-devices
  Detected sound devices:
  ...
  
  % paging --dump-conf
  ;; Current configuration options
  ...

  As usual, there should be no error messages for these commands.

  To return back to root shell after running su - paging command above (should be still active), exit command can be used or a “Ctrl + d” key combo.

  To later get back to same “paging” user shell and installed python virtualenv, use the following commands (same as used above during virtualenv setup):

  % su - paging
  % . PagingServer/bin/activate

  Any (at least non system-wide) python stuff for the app should be tweaked or installed only after running these (and until exiting the shell).

• (optional) Start JACK sound server.

  It is important to do this before running PagingServer, as the latter depends on jackd in general, though can start it by itself with “jack-autostart = yes” configuration option.

  Unless that option will be used (not recommended, as there might be other apps still needing JACK to be started explicitly - e.g. music players), JACK daemon (jackd) should be always started before PagingServer, using the same uid (“paging”) as the app.

  Start jackd in one of the following ways (assuming initial root shell):

  % sudo -u paging -- setsid jackd --nozombies -d dummy &
  % disown
  
  ### or
  
  % su - paging
  % setsid jackd --nozombies -d dummy &
  % disown
  
  ### or (if systemd is used in OS as init)
  
  % systemd-run --uid=paging -- jackd --nozombies -d dummy

  Here -d dummy output is used to avoid relying on any particular sound hardware available.

  Any ALSA (linux audio hardware stack) devices can be connected to this jackd server later via “alsa_in” / “alsa_out” commands, installed along with JACK1 server.

  See JACK documentation (for particular fork that is used, as this process is different between JACK1 / JACK2) for more details on how to connect this sound server to the actual audio hardware.

  Started without any extra options (on top of what’s shown above), this jackd will have “default” server name, and should be used by default by all jack-enabled apps (e.g. music players and such), including PagingServer itself.

• Configure PagingServer and install binary/configuration files for running it as a system service.

  Install symlink to a “paging” script into system-wide $PATH (as root):

  % ln -s ~paging/PagingServer/bin/paging /usr/local/bin/
  
  % paging --version
  paging version-unknown (see python package version)

  Despite binary being available to all users after that, DO NOT run the actual service as a “root” user, at least outside of very exceptional cases (e.g. maybe checking if it works as root due to dev/file access permissions).

  Get annotated paging.example.conf from the github repository or pypi package (included there, but not actually installed):

  % wget https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/paging.example.conf
  ### or
  % curl -O https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/paging.example.conf

  Edit file as necessary (see comments there and usage/configuration-related info in this README), and put it to /etc/paging.conf (requires root privileges):

  % nano paging.example.conf
  % install -o root -g paging -m640 -T paging.example.conf /etc/paging.conf

  /etc/paging.conf is one of the default locations where app looks for configuration file (see paging --help output for a full list of such locations).

  Test-run the service as a proper “paging” user (created in previous step) in one of the following ways (assuming starting shell is root):

  % sudo -u paging -- paging --debug
  
  ### or
  
  % su - paging
  % paging --debug
  
  ### or (if systemd is used in OS as init)
  
  % systemd-run --uid=paging -- paging --debug
  % journalctl -n30 -af  # to see output of the ad-hoc service there

  If correctly configured and working, there should be plenty of “DEBUG” output (due to --debug option in commands above), but no errors, especially fatal ones that cause the app to crash.

• Configure system to run PagingServer and jackd on boot and start these as system services.

  Most linux distros these days run systemd as an init (pid-1), so instructions below are more detailed for that scenario.

  • With systemd as os init.

    Install python-systemd for python 2.7:

    • Arch Linux: pacman -S python2-systemd

    • Debian Jessie:

      At least as of now (2015-08-16), there’s no prebuilt bindings package for python 2.7, which was dropped due to maintainer decision, given that nothing (yet) in debian depended on it.

      Rebuild “systemd” packages manually with python2 instead of python3:

      % apt-get install packaging-dev python-lxml
      % apt-get build-dep systemd
      
      % apt-get source systemd
      % cd systemd-215
      
      % mv debian/python{3,}-systemd.install
      % sed -i \
        -e 's/python3/python2/' \
        -e 's/--without-python/--with-python/' \
        debian/rules
      % sed -i \
        -e 's/python3-all-dev/python-dev/' \
        -e 's/python3-lxml/python-lxml/' \
        -e 's/python3-systemd/python-systemd/' \
        -e 's/python3:Depends/python:Depends/' \
        -e 's/Python 3/Python 2/' \
        debian/control
      ### last two "sed" commands above are both one-liners,
      ###  wrapped for readability
      
      % fakeroot debian/rules binary
      ### this might take a while...
      
      % apt-get markauto python-lxml \
        $( apt-cache showsrc systemd | sed -e \
          '/Build-Depends/!d;s/Build-Depends: \|,\|([^)]*),*\|\[[^]]*\]//g' )
      ### also all on one line
      
      % apt-get remove packaging-dev
      % apt-get autoremove
      
      % dpkg -i ../python-systemd_215-17+deb8u1_amd64.deb

      If that doesn’t work for whatever reason, and the installed OS arch is x86_64 (amd64), then there’s also an option to try the package I’ve built directly:

      % wget http://fraggod.net/static/mirror/packages/python-systemd_215-17%2bdeb8u1_amd64.deb
      
      % sha256sum python-systemd_215-17+deb8u1_amd64.deb
      02fbec7a120ab2597a784df44cfa85d31aacbdf725782bb3413436702babe955 ...
      ### ^^^ make sure sha256sum of the downloaded package matches that ^^^
      
      % dpkg -i python-systemd_215-17+deb8u1_amd64.deb

      Should likely work on any Debian Jessie, even with any of the later systemd patchsets (i.e. beyond 17).

      Otherwise, if neither of above options to install python-systemd works, it should be fine to just drop the --systemd option (and associated stuff) from the paging.service file.

      See “Running as a systemd service” in the “Usage” section for more details on how to do that.

    • For Debian Sid or any other distro, either:

      • Install from distro package repositories, if available (recommended).

      • Install into virtualenv (setup in one of the previous steps) from python-systemd repository directly:

        % su - paging
        % . PagingServer/bin/activate
        % pip install git+https://github.com/systemd/python-systemd
        % exit

        Separate python-systemd bindings are only available starting from systemd-223 (when they were split), so it might not work for earlier systemd versions.

    If systemd python bindings are going to be used, make sure that they can be imported from python2:

    % python2 -c 'import systemd.daemon; print systemd.daemon.__version__'
    215

    Get systemd unit files for paging.service and jack@.service from the github repository and install these to /etc/systemd/system directory:

    % cd /etc/systemd/system
    
    % wget https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/paging.service
    % wget https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/jack@.service
    
    ### or
    
    % curl -O https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/paging.service
    % curl -O https://raw.githubusercontent.com/AccelerateNetworks/PagingServer/master/jack@.service

    Note that both .service files assume that app will be run with the user and paths (config, script symlink) from the steps above, and should be changed if other uid/paths should be used.

    See “Running as a systemd service” (under “Usage”) for more details on contents and editing of these files.

    Make sure that jackd and/or PagingServer are not currently running (especially if were started in previous steps above):

    % pkill -x jackd
    % pkill -f paging

    Start both services:

    % systemctl start jack@paging paging

    Verify that both were started and are running correctly:

    % systemctl status jack@paging paging
    
    ● jack@paging.service
       Loaded: loaded (/etc/systemd/system/jack@.service; disabled)
       Active: active (running) since Sun 2015-08-16 08:20:28 EDT; 3min 32s ago
    ...
    
    ● paging.service
       Loaded: loaded (/etc/systemd/system/paging.service; disabled)
       Active: active (running) since Sun 2015-08-16 08:20:30 EDT; 3min 30s ago
    ...

    If there were any errors logged, last 10 lines of these should be presented in the “status” command output above,

    journalctl -ab command can be used to see all combined logging produced by system services since boot, and journalctl -ab -u paging can further limit that to a single unit (to e.g. see error tracebacks there).

    journalctl -af can be used to continously follow what is being logged (like tail -f for all system logs), optionally with the same “-u” option.

    At any point these services can be stopped/started/restarted using “systemctl” command, as described in more detail in “Usage” section.

    Enable JACK and PagingServer to start on OS boot:

    % systemctl enable jack@paging paging
    
    Created symlink from ... to /etc/systemd/system/jack@.service.
    Created symlink from ... to /etc/systemd/system/paging.service.

    Note that “systemctl enable” won’t start the services right away, “start” can be used to do that separately.

    Verify or check whether paging.service and jack@paging.service are enabled to start on boot:

    % systemctl is-enabled jack@paging paging
    enabled
    enabled

    There should be one “enabled” message for each.

  • With SysV init (/etc/init.d/ scripts) or any other init system.

    Both commands from ExecStart=... lines in paging.service and jack@.service in the github repository should be scheduled to run on boot as specific user (e.g. “paging”) and “backgrounded”.

    From any sh/bash script (running as root) it’s fairly easy to do this by adding the following lines:

    sudo -u paging -- setsid paging &
    disown
    sudo -u paging -- setsid jackd --nozombies --no-realtime -d dummy &
    disown

    On many “classic” sysvinit/rc.d systems it can be done by adding these to /etc/rc.local, or creating a separate initscript for these in /etc/init.d or /etc/rc.d.

    Other init systems like openrc, runit, upstart can have their own ways to achieve same results, which should be fairly trivial to configure by following their docs.

  With this step completed, PagingServer should be starting properly after reboot, which is a good idea to test by rebooting the machine, to avoid future surprises, if that is possible/acceptable for a particular server where it is installed.

If anything in the steps above is unclear, misleading or does not work, and can be fixed, please leave a comment on- or file a new github issue, describing what’s wrong and how it can be done better or corrected.

More info on how to file these in a most efficient, useful and productive way can be found e.g. in this “Filing Effective Bug Reports” article.

Audio configuration

Overview of the software stack related to audio flow:

• PJSUA picks-up the calls, decoding audio streams from SIP connections.

• PJSUA outputs call audio to via PortAudio.

• PortAudio can use multiple backends on linux systems, including:

  • ALSA libs (and straight down to linux kernel)

  • OSS (/dev/dsp*, only supported through emulation layer in modern kernels)

  • JACK sound server

  • PulseAudio sound server (with a somewhat unstable patch, see comment on #3 for details)

  In this particular implementation, JACK backend is used, as it is necessary to later multiplex PJSUA output to multiple destinations and mix-in sounds from other sources there.

  So PortAudio sends sound stream to JACK.

• JACK serves as a “hub”, receiving streams from music players (mpd instances), klaxon sounds, calls picked-up by PJSUA.

  JACK mixes these streams together, muting and connecting/disconnecting some as necessary, controlled by the server script (“paging”).

  End result is N stream(s) corresponding to (N) configured hardware output(s).

• JACK outputs resulting sound stream(s) through ALSA libs (and linux from there) to the sound hardware.

Hence audio configuration can be roughly divided into these sections (at the moment):

• Sound output settings for PJSUA.

  Related configuration options:

  • pjsua-device

  • pjsua-conf-port

  As PortAudio (used by pjsua) can use one (and only one) of multiple backends at a time, and each of these backend can have multiple “ports” in turn, pjsua-device should be configured to use JACK backend “device”.

  To see all devices that PJSUA and PortAudio detects, run:

  % paging --dump-pjsua-devices
  
  Detected sound devices:
    [0] HDA ATI SB: ID 440 Analog (hw:0,0)
    [1] HDA ATI SB: ID 440 Digital (hw:0,3)
    [2] HDA ATI HDMI: 0 (hw:1,3)
    [3] sysdefault
    [4] front
    [5] surround21
    [6] surround40
    ...
    [13] dmix
    [14] default
    [15] system
    [16] PulseAudio JACK Source

  (output is truncated, as it also includes misc info for each of these devices/ports that PortAudio/PJSUA provides)

  This should print a potentially-long list of “playback devices” (PJSUA terminology) that can be used for output there, as shown above.

  JACK default output (as created by e.g. -d dummy option to jackd) in the example list above is called “system” - same as in JACK, and should be matched by default.

  If any other JACK-input/PortAudio-output should be used, it can be specified either as numeric id (number in square brackets on the left) or regexp (python style) to match against name in the list.

  To avoid having any confusing non-JACK ports there, PortAudio can be compiled with only JACK as a backend.

  pjsua-conf-port option can be used to match one of the “conference ports” from paging --dump-pjsua-conf-ports command output in the same fashion, if there will ever be more than one (due to more complex pjsua configuration, for example), otherwise it’ll work fine with empty default.

• JACK daemon startup and control client connection configuration.

  Related configuration options:

  • jack-autostart

  • jack-server-name

  • jack-client-name

  All of these are common JACK client settings, described in jackd(1), jackstart(1) manpages, libjack or jack-client module documentation.

  With exception for self-explanatory jack-autostart (enabled by default), these options should be irrelevant, unless this script is used with multiple JACK instances or clients.

• Configuration for any non-call inputs (music, klaxons, etc) for JACK.

  Related configuration options:

  • klaxon

  • jack-music-client-name

  • jack-music-links

  “klaxon” can be a path to any file that has sound in it (that ffmpeg would understand), and will be played before each announcement call on all “jack-output-ports” (see below), and before that call gets answered.

  “jack-music-client-name” should be a regexp to match outputs of music clients, that should play stuff in-between announcements, and “jack-music-links” allows to control which set(s) of speakers they’ll be connected to.

  For example, if mpd.conf has something like this:

  audio_output {
    type "jack"
    name "jack"
    client_name "mpd.paging:test"
  }

  Then configuration like this (these are actually defaults):

  jack-music-client-name = ^mpd\.paging:(.*)$
  jack-music-links = left---left right---right

  Will connect output from that player to all speakers matched by “jack-output-ports” (all available to JACK by default).

  Script can be run with --dump-jack-ports option to show all JACK ports that are currently available - all connected players, speakers, cards and such.

  See more detailed description of these options and how they’re interpreted in paging.example.conf.

• List of hardware outputs (ALSA PCMs) to use as JACK final outputs/sinks.

  Related configuration options:

  • jack-output-ports

  Same as with PJSUA outputs/ports above, jack-output-ports can be enumerated via paging --dump-jack-ports command, and filtered by direct id or name regexp, if necessary.

  Default is to route PJSUA call to all outputs available in JACK.

All settings mentioned here are located in the [audio] section of the configuration file.

See paging.example.conf for more detailed descriptons.

Pre-convert klaxon sound(s) to wav from any format

Can be done via ffmpeg with:

ffmpeg -y -v 0 -i sample.mp3 -f wav sample.wav

Where it doesn’t actually matter which format source “sample.mp3” is in - can be mp3, ogg, aac, mpc, mp4 or whatever else ffmpeg supports.

Might help to avoid startup delays due to conversion of these on each run.

If pjsua will be complaining about sample-rate difference between wav file and output, e.g. -ar 44100 option can be used (after -f wav) to have any sampling rate for the output file.

Running JACK on a system where PulseAudio is the main sound server

First of all, jackd has to be started manually there, and strictly before pulseaudio server.

/etc/pulse/default.pa should have something like this at the end (after default sink - probably alsa - init!):

load-module module-jack-source source_name=jack_in
load-module module-loopback source=jack_in

That will create an output from JACK to PulseAudio and from there to whatever actually makes sound on the particular system, provided that the loopback stream and source in question are not muted and have some non-zero volume set in pulse.

“module-jack-source” has options for picking which jackd to connect to, if isn’t not “default”, “module-loopback” after it creates a stream from that jack source to a default sink (which is probably an ALSA sink).

On the JACK side, “PulseAudio JACK Source” port (sink) gets created, and anything connected there will make its way to pulseaudio.

Running mpd player connected to JACK

Music Player Daemon (mpd) is a nice player, well-suited for purposes of hands-off playing music all day long in-between any kind of announcements.

It also has a vast number of clients, including evertyhing from IR remote listeners (via lirc), bluetooth phones, car stereos, to more conventional desktop apps and WebUIs.

Example configuration for mpd with JACK output and “client_name” recognized by default PagingServer configuration and suitable for playing pretty much anything:

log_file "/dev/stdout"
music_directory "/mnt/music"

# password "super-secret-admin-password@read,add,control,admin"
# password "password-for-teh-peeple@read,add,control"

input {
  plugin "curl"
}

audio_output {
  type "jack"
  name "jack"
  client_name "mpd.paging:test"
  autostart "no"
}

Note that “password” lines are commented-out, which will allow any client to connect without any kind of authorization, so it might be a good idea to change these if control port is to be exposed to any kind of non-localhost network.

Benchmark script (callram.py)

Description below is from old README.md file pretty much verbatim.

We’ve tested this script with thousands of calls, it is fairly reliable and light on resources. Total CPU use on a Pentium 4 @ 2.8ghz hovered around 0.5% with 4MB ram usage. identical figures were observed on a Celeron D @ 2.53Ghz, you could probably get away with whatever your operating system requires to run in terms of hardware.

To benchmark, you’ll need to set up callram.py.

• Setting up callram.py

  This setup assumes you have PJSUA installed, if not, go back to Installation earlier in this readme and install it.

• Put the files in the right places:

  sudo cp callram.py /opt/bin/callram.py
  sudo cp callram.example.conf /etc/callram.conf

• Add your SIP account:

  sudo nano /etc/callram.conf

  Change the top 3 values to your SIP server, username (usually ext. number) and password.

  Then fill in both SIP URI: fields (uri= and to=) with the SIP URI of the client you’d like to test.

  SIP URIs are usually formatted as sip:<extension#>@<exampledomain.com> in most cases.

  The Domain may sometimes be an IPv4 or IPv6 address depending on your setup.

• Run:

  /usr/bin/python /opt/bin/callram.py

Sending error reports to Sentry

Sentry is a “modern error logging and aggregation platform”.

Python raven module has to be installed in order for this to work.

If you followed step-by-step installation instructions from this README, then it should be installed into the same virtualenv as the PagingServer itself, i.e. from a root shell run:

% su - paging
% . PagingServer/bin/activate
% pip install raven
% exit

Otherwise that module can be installed from an OS package, if available (recommended), or via standard python packaging tools (see python packaging tutorial).

Then uncomment and/or set “sentry_dsn” option under the [server] section of the configuration file.

It can also be set via --sentry-dsn command-line option, e.g. in systemd unit distributed with the package, to apply on all setups where package is deployed.