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A system for controlling process state under UNIX

Project description


Supervisor is a client/server system that allows its users to
control a number of processes on UNIX-like operating systems.

Supported Platforms

Supervisor has been tested and is known to run on Linux (Ubuntu), Mac OS X
(10.4, 10.5, 10.6), and Solaris (10 for Intel) and FreeBSD 6.1. It will
likely work fine on most UNIX systems.

Supervisor will not run at all under any version of Windows.

Supervisor is known to work with Python 2.4 or later but will not work
under any version of Python 3.


You can view the current Supervisor documentation online `in HTML format
<>`_ . This is where you should go for detailed
installation and configuration documentation.

Mailing list, Reporting Bugs, and Viewing the Source Repository

You may subscribe to the `Supervisor-users mailing list

Please report bugs in the `Github issue tracker
<>`_. .

You can view the source repository for supervisor via


If you'd like to contribute to supervisor directly, please contact the
`Supervisor-users mailing list

3.1.2 (2014-09-07)

- Fixed a bug where ``tail group:*`` in ``supervisorctl`` would show a 500
Internal Server Error rather than a BAD_NAME fault.

- Fixed a bug where the web interface would show a 500 Internal Server Error
instead of an error message for some process start faults.

- Removed medusa files not used by Supervisor.

3.1.1 (2014-08-11)

- Fixed a bug where ``supervisorctl tail -f name`` output would stop if log
rotation occurred while tailing.

- Prevent a crash when a greater number file descriptors were attempted to be
opened than permitted by the environment when starting a bunch of programs.
Now, instead a spawn error is logged.

- Compute "channel delay" properly, fixing symptoms where a supervisorctl start
command would hang for a very long time when a process (or many processes)
are spewing to their stdout or stderr. See comments attached to .

- Added docs/, docs/Makefile, and supervisor/scripts/*.py to
the release package.

3.1.0 (2014-07-29)

- The output of the ``start``, ``stop``, ``restart``, and ``clear`` commands
in ``supervisorctl`` has been changed to be consistent with the ``status``
command. Previously, the ``status`` command would show a process like
``foo:foo_01`` but starting that process would show ``foo_01: started``
(note the group prefix ``foo:`` was missing). Now, starting the process
will show ``foo:foo_01: started``. Suggested by Chris Wood.

- The ``status`` command in ``supervisorctl`` now supports group name
syntax: ``status group:*``.

- The process column in the table output by the ``status`` command in
``supervisorctl`` now expands to fit the widest name.

- The ``update`` command in ``supervisorctl`` now accepts optional group
names. When group names are specified, only those groups will be
updated. Patch by Gary M. Josack.

- Tab completion in ``supervisorctl`` has been improved and now works for
more cases. Thanks to Mathieu Longtin and Marc Abramowitz for the patches.

- Attempting to start or stop a process group in ``supervisorctl`` with the
``group:*`` syntax will now show the same error message as the ``process``
syntax if the name does not exist. Previously, it would show a Python
exception. Patch by George Ang.

These events are fired when process groups are added or removed from
Supervisor's runtime configuration when using the ``add`` and ``remove``
commands in ``supervisorctl``. Patch by Brent Tubbs.

- Stopping a process in the backoff state now changes it to the stopped
state. Previously, an attempt to stop a process in backoff would be
ignored. Patch by Pascal Varet.

- The ``directory`` option is now expanded separately for each process in
a homogeneous process group. This allows each process to have its own
working directory. Patch by Perttu Ranta-aho.

- Removed ``setuptools`` from the ``requires`` list in ```` because
it caused installation issues on some systems.

- Fixed a bug in Medusa where the HTTP Basic authorizer would cause an
exception if the password contained a colon. Thanks to Thomas Guttler
for reporting this issue.

- Fixed an XML-RPC bug where calling supervisor.clearProcessLogs() with a
name like ``group:*`` would cause a 500 Internal Server Error rather than
returning a BAD_NAME fault.

- Fixed a hang that could occur in ``supervisord`` if log rotation is used
and an outside program deletes an active log file. Patch by Magnus Lycka.

- A warning is now logged if a glob pattern in an ``[include]`` section does
not match any files. Patch by Daniel Hahler.

3.0 (2013-07-30)

- Parsing the config file will now fail with an error message if a process
or group name contains characters that are not compatible with the
eventlistener protocol.

- Fixed a bug where the ``tail -f`` command in ``supervisorctl`` would fail
if the combined length of the username and password was over 56 characters.

- Reading the config file now gives a separate error message when the config
file exists but can't be read. Previously, any error reading the file
would be reported as "could not find config file". Patch by Jens Rantil.

- Fixed an XML-RPC bug where array elements after the first would be ignored
when using the ElementTree-based XML parser. Patch by Zev Benjamin.

- Fixed the usage message output by ``supervisorctl`` to show the correct
default config file path. Patch by Alek Storm.

3.0b2 (2013-05-28)

- The behavior of the program option ``user`` has changed. In all previous
versions, if ``supervisord`` failed to switch to the user, a warning would
be sent to the stderr log but the child process would still be spawned.
This means that a mistake in the config file could result in a child
process being unintentionally spawned as root. Now, ``supervisord`` will
not spawn the child unless it was able to successfully switch to the user.
Thanks to Igor Partola for reporting this issue.

- If a user specified in the config file does not exist on the system,
``supervisord`` will now print an error and refuse to start.

- Reverted a change to logging introduced in 3.0b1 that was intended to allow
multiple processes to log to the same file with the rotating log handler.
The implementation caused supervisord to crash during reload and to leak
file handles. Also, since log rotation options are given on a per-program
basis, impossible configurations could be created (conflicting rotation
options for the same file). Given this and that supervisord now has syslog
support, it was decided to remove this feature. A warning was added to the
documentation that two processes may not log to the same file.

- Fixed a bug where parsing ``command=`` could cause supervisord to crash if
shlex.split() fails, such as a bad quoting. Patch by Scott Wilson.

- It is now possible to use ``supervisorctl`` on a machine with no
``supervisord.conf`` file by supplying the connection information in
command line options. Patch by Jens Rantil.

- Fixed a bug where supervisord would crash if the syslog handler was used
and supervisord received SIGUSR2 (log reopen request).

- Fixed an XML-RPC bug where calling supervisor.getProcessInfo() with a bad
name would cause a 500 Internal Server Error rather than the returning
a BAD_NAME fault.

- Added a favicon to the web interface. Patch by Caio Ariede.

- Fixed a test failure due to incorrect handling of daylight savings time
in the childutils tests. Patch by Ildar Hizbulin.

- Fixed a number of pyflakes warnings for unused variables, imports, and
dead code. Patch by Philippe Ombredanne.

3.0b1 (2012-09-10)

- Fixed a bug where parsing ``environment=`` did not verify that key/value
pairs were correctly separated. Patch by Martijn Pieters.

- Fixed a bug in the HTTP server code that could cause unnecessary delays
when sending large responses. Patch by Philip Zeyliger.

- When supervisord starts up as root, if the ``-c`` flag was not provided, a
warning is now emitted to the console. Rationale: supervisord looks in the
current working directory for a ``supervisord.conf`` file; someone might
trick the root user into starting supervisord while cd'ed into a directory
that has a rogue ``supervisord.conf``.

- A warning was added to the documentation about the security implications of
starting supervisord without the ``-c`` flag.

- Add a boolean program option ``stopasgroup``, defaulting to false.
When true, the flag causes supervisor to send the stop signal to the
whole process group. This is useful for programs, such as Flask in debug
mode, that do not propagate stop signals to their children, leaving them

- Python 2.3 is no longer supported. The last version that supported Python
2.3 is Supervisor 3.0a12.

- Removed the unused "supervisor_rpc" entry point from

- Fixed a bug in the rotating log handler that would cause unexpected
results when two processes were set to log to the same file. Patch
by Whit Morriss.

- Fixed a bug in config file reloading where each reload could leak memory
because a list of warning messages would be appended but never cleared.
Patch by Philip Zeyliger.

- Added a new Syslog log handler. Thanks to Denis Bilenko, Nathan L. Smith,
and Jason R. Coombs, who each contributed to the patch.

- Put all change history into a single file (CHANGES.txt).

3.0a12 (2011-12-06)

- Released to replace a broken 3.0a11 package where non-Python files were
not included in the package.

3.0a11 (2011-12-06)

- Added a new file, ``PLUGINS.rst``, with a listing of third-party plugins
for Supervisor. Contributed by Jens Rantil.

- The ``pid`` command in supervisorctl can now be used to retrieve the PIDs
of child processes. See ``help pid``. Patch by Gregory Wisniewski.

- Added a new ``host_node_name`` expansion that will be expanded to the
value returned by Python's ``platform.node`` (see
Patch by Joseph Kondel.

- Fixed a bug in the web interface where pages over 64K would be truncated.
Thanks to Drew Perttula and Timothy Jones for reporting this.

- Renamed ``README.txt`` to ``README.rst`` so GitHub renders the file as

- The XML-RPC server is now compatible with clients that do not send empty
<params> when there are no parameters for the method call. Thanks to
Johannes Becker for reporting this.

- Fixed ``supervisorctl --help`` output to show the correct program name.

- The behavior of the configuration options ``minfds`` and ``minprocs`` has
changed. Previously, if a hard limit was less than ``minfds`` or
``minprocs``, supervisord would unconditionally abort with an error. Now,
supervisord will attempt to raise the hard limit. This may succeed if
supervisord is run as root, otherwise the error is printed as before.
Patch by Benoit Sigoure.

- Add a boolean program option ``killasgroup``, defaulting to false,
if true when resorting to send SIGKILL to stop/terminate the process
send it to its whole process group instead to take care of possible
children as well and not leave them behind. Patch by Samuele Pedroni.

- Environment variables may now be used in the configuration file
for options that support string expansion. Patch by Aleksey Sivokon.

- Fixed a race condition where supervisord might not act on a signal sent
to it. Thanks to Adar Dembo for reporting the issue and supplying the
initial patch.

- Updated the output of ``echo_supervisord_conf`` to fix typos and
improve comments. Thanks to Jens Rantil for noticing these.

- Fixed a possible 500 Server Error from the web interface. This was
observed when using Supervisor on a domain socket behind Nginx, where
Supervisor would raise an exception because REMOTE_ADDR was not set.
Patch by David Bennett.

3.0a10 (2011-03-30)

- Fixed the stylesheet of the web interface so the footer line won't overlap
a long process list. Thanks to Derek DeVries for the patch.

- Allow rpc interface plugins to register new events types.

- Bug fix for FCGI sockets not getting cleaned up when the ``reload`` command
is issued from supervisorctl. Also, the default behavior has changed for
FCGI sockets. They are now closed whenever the number of running processes
in a group hits zero. Previously, the sockets were kept open unless a
group-level stop command was issued.

- Better error message when HTTP server cannot reverse-resolve a hostname to
an IP address. Previous behavior: show a socket error. Current behavior:
spit out a suggestion to stdout.

- Environment variables set via ``environment=`` value within
``[supervisord]`` section had no effect. Thanks to Wyatt Baldwin
for a patch.

- Fix bug where stopping process would cause process output that happened
after the stop request was issued to be lost. See

- Moved 2.X change log entries into ``HISTORY.txt``.

- Converted ``CHANGES.txt`` and ``README.txt`` into proper ReStructuredText
and included them in the ``long_description`` in ````.

- Added a tox.ini to the package (run via ``tox`` in the package dir). Tests
supervisor on multiple Python versions.

3.0a9 (2010-08-13)

- Use rich comparison methods rather than __cmp__ to sort process configs and
process group configs to better straddle Python versions. (thanks to
Jonathan Riboux for identifying the problem and supplying an initial

- Fixed test_supervisorctl.test_maintail_dashf test for Python 2.7. (thanks
to Jonathan Riboux for identifying the problem and supplying an initial

- Fixed the way that supervisor.datatypes.url computes a "good" URL
for compatibility with Python 2.7 and Python >= 2.6.5. URLs with
bogus "schemes://" will now be accepted as a version-straddling
compromise (before they were rejected before supervisor would
start). (thanks to Jonathan Riboux for identifying the problem
and supplying an initial patch).

- Add a ``-v`` / ``--version`` option to supervisord: Print the
supervisord version number out to stdout and exit. (Roger Hoover)

- Import iterparse from xml.etree when available (eg: Python 2.6). Patch
by Sidnei da Silva.

- Fixed the url to the supervisor-users mailing list. Patch by
Sidnei da Silva

- When parsing "environment=" in the config file, changes introduced in
3.0a8 prevented Supervisor from parsing some characters commonly
found in paths unless quoting was used as in this example::


Supervisor once again allows the above line to be written as::


Alphanumeric characters, "_", "/", ".", "+", "-", "(", ")", and ":" can all
be used as a value without quoting. If any other characters are needed in
the value, please quote it as in the first example above. Thanks to Paul
Heideman for reporting this issue.

- Supervisor will now look for its config file in locations relative to the
executable path, allowing it to be used more easily in virtual
environments. If sys.argv[0] is ``/path/to/venv/bin/supervisorctl``,
supervisor will now look for it's config file in
``/path/to/venv/etc/supervisord.conf`` and
``/path/to/venv/supervisord.conf`` in addition to the other standard
locations. Patch by Chris Rossi.

3.0a8 (2010-01-20)

- Don't cleanup file descriptors on first supervisord invocation:
this is a lame workaround for Snow Leopard systems that use
libdispatch and are receiving "Illegal instruction" messages at
supervisord startup time. Restarting supervisord via
"supervisorctl restart" may still cause a crash on these systems.

- Got rid of Medusa hashbang headers in various files to ease RPM

- Allow umask to be 000 (patch contributed by Rowan Nairn).

- Fixed a bug introduced in 3.0a7 where supervisorctl wouldn't ask
for a username/password combination properly from a
password-protected supervisord if it wasn't filled in within the
"[supervisorctl]" section username/password values. It now
properly asks for a username and password.

- Fixed a bug introduced in 3.0a7 where would not detect the
Python version correctly. Patch by Daniele Paolella.

- Fixed a bug introduced in 3.0a7 where parsing a string of key/value
pairs failed on Python 2.3 due to use of regular expression syntax
introduced in Python 2.4.

- Removed the test suite for the ``memmon`` console script, which was
moved to the Superlance package in 3.0a7.

- Added release dates to CHANGES.txt.

- Reloading the config for an fcgi process group did not close the fcgi
socket - now, the socket is closed whenever the group is stopped as a unit
(including during config update). However, if you stop all the processes
in a group individually, the socket will remain open to allow for graceful
restarts of FCGI daemons. (Roger Hoover)

- Rereading the config did not pick up changes to the socket parameter in a
fcgi-program section. (Roger Hoover)

- Made a more friendly exception message when a FCGI socket cannot be
created. (Roger Hoover)

- Fixed a bug where the --serverurl option of supervisorctl would not
accept a URL with a "unix" scheme. (Jason Kirtland)

- Running the tests now requires the "mock" package. This dependency has
been added to "tests_require" in (Roger Hoover)

- Added support for setting the ownership and permissions for an FCGI socket.
This is done using new "socket_owner" and "socket_mode" options in an
[fcgi-program:x] section. See the manual for details. (Roger Hoover)

- Fixed a bug where the FCGI socket reference count was not getting
decremented on spawn error. (Roger Hoover)

- Fixed a Python 2.6 deprecation warning on use of the "sha" module.

- Updated to one that knows about setuptools 0.6c11.

- Running "supervisorctl shutdown" no longer dumps a Python backtrace
when it can't connect to supervisord on the expected socket. Thanks
to Benjamin Smith for reporting this.

- Removed use of collections.deque in our bundled version of asynchat
because it broke compatibility with Python 2.3.

- The sample configuration output by "echo_supervisord_conf" now correctly
shows the default for "autorestart" as "unexpected". Thanks to
William Dode for noticing it showed the wrong value.

3.0a7 (2009-05-24)

- We now bundle our own patched version of Medusa contributed by Jason
Kirtland to allow Supervisor to run on Python 2.6. This was done
because Python 2.6 introduced backwards incompatible changes to
asyncore and asynchat in the stdlib.

- The console script ``memmon``, introduced in Supervisor 3.0a4, has
been moved to Superlance (
The Superlance package contains other useful monitoring tools designed
to run under Supervisor.

- Supervisorctl now correctly interprets all of the error codes that can
be returned when starting a process. Patch by Francesc Alted.

- New ``stdout_events_enabled`` and ``stderr_events_enabled`` config options
have been added to the ``[program:x]``, ``[fcgi-program:x]``, and
``[eventlistener:x]`` sections. These enable the emitting of new
PROCESS_LOG events for a program. If unspecified, the default is False.

If enabled for a subprocess, and data is received from the stdout or
stderr of the subprocess while not in the special capture mode used by
PROCESS_COMMUNICATION, an event will be emitted.

Event listeners can subscribe to either PROCESS_LOG_STDOUT or
PROCESS_LOG_STDERR individually, or PROCESS_LOG for both.

- Values for subprocess environment variables specified with environment=
in supervisord.conf can now be optionally quoted, allowing them to
contain commas. Patch by Tim Godfrey.

- Added a new event type, REMOTE_COMMUNICATION, that is emitted by a new
RPC method, supervisor.sendRemoteCommEvent().

- Patch for bug #268 (KeyError on ``here`` expansion for
stdout/stderr_logfile) from David E. Kindred.

- Add ``reread``, ``update``, and ``avail`` commands based on Anders
Quist's ``online_config_reload.diff`` patch. This patch extends
the "add" and "drop" commands with automagical behavior::

In supervisorctl:

supervisor> status
bar RUNNING pid 14864, uptime 18:03:42
baz RUNNING pid 23260, uptime 0:10:16
foo RUNNING pid 14866, uptime 18:03:42
gazonk RUNNING pid 23261, uptime 0:10:16
supervisor> avail
bar in use auto 999:999
baz in use auto 999:999
foo in use auto 999:999
gazonk in use auto 999:999
quux avail auto 999:999

Now we add this to our conf:


Then we reread conf:

supervisor> reread
baz: disappeared
gazonk: disappeared
quux: available
zegroup: available
supervisor> avail
bar in use auto 999:999
foo in use auto 999:999
quux avail auto 999:999
zegroup:baz avail auto 999:999
zegroup:gazonk avail auto 999:999
supervisor> status
bar RUNNING pid 14864, uptime 18:04:18
baz RUNNING pid 23260, uptime 0:10:52
foo RUNNING pid 14866, uptime 18:04:18
gazonk RUNNING pid 23261, uptime 0:10:52

The magic make-it-so command:

supervisor> update
baz: stopped
baz: removed process group
gazonk: stopped
gazonk: removed process group
zegroup: added process group
quux: added process group
supervisor> status
bar RUNNING pid 14864, uptime 18:04:43
foo RUNNING pid 14866, uptime 18:04:43
quux RUNNING pid 23561, uptime 0:00:02
zegroup:baz RUNNING pid 23559, uptime 0:00:02
zegroup:gazonk RUNNING pid 23560, uptime 0:00:02
supervisor> avail
bar in use auto 999:999
foo in use auto 999:999
quux in use auto 999:999
zegroup:baz in use auto 999:999
zegroup:gazonk in use auto 999:999

- Fix bug with symptom "KeyError: 'process_name'" when using a logfile name
including documented``process_name`` Python string expansions.

- Tab completions in the supervisorctl shell, and a foreground mode for
Supervisor, implemented as a part of GSoC. The supervisorctl program now
has a ``fg`` command, which makes it possible to supply inputs to a
process, and see its output/error stream in real time.

- Process config reloading implemented by Anders Quist. The
supervisorctl program now has the commands "add" and "drop".
"add <programname>" adds the process group implied by <programname>
in the config file. "drop <programname>" removes the process
group from the running configuration (it must already be stopped).
This makes it possible to add processes to and remove processes from
a running supervisord without restarting the supervisord process.

- Fixed a bug where opening the HTTP servers would fail silently
for socket errors other than errno.EADDRINUSE.

- Thanks to Dave Peticolas, using "reload" against a supervisord
that is running in the background no longer causes supervisord
to crash.

- Configuration options for logfiles now accept mixed case reserved
words (e.g. "AUTO" or "auto") for consistency with other options.

- childutils.eventdata was buggy, it could not deal with carriage returns
in data. See Thanks
to Ian Bicking.

- Per-process exitcodes= configuration now will not accept exit
codes that are not 8-bit unsigned integers (supervisord will not
start when one of the exit codes is outside the range of 0 - 255).

- Per-process ``directory`` value can now contain expandable values like
``%(here)s``. (See

- Accepted patch from Roger Hoover to allow for a new sort of
process group: "fcgi-program". Adding one of these to your
supervisord.conf allows you to control fastcgi programs. FastCGI
programs cannot belong to heterogenous groups.

The configuration for FastCGI programs is the same as regular programs
except an additional "socket" parameter. Substitution happens on the
socket parameter with the ``here`` and ``program_name`` variables::


- Supervisorctl now supports a plugin model for supervisorctl

- Added the ability to retrieve supervisord's own pid through
supervisor.getPID() on the XML-RPC interface or a new
"pid" command on supervisorctl.

3.0a6 (2008-04-07)

- The RotatingFileLogger had a race condition in its doRollover
method whereby a file might not actually exist despite a call to
os.path.exists on the line above a place where we try to remove
it. We catch the exception now and ignore the missing file.

3.0a5 (2008-03-13)

- Supervisorctl now supports persistent readline history. To
enable, add "history_file = <pathname>" to the ``[supervisorctl]``
section in your supervisord.conf file.

- Multiple commands may now be issued on one supervisorctl command
line, e.g. "restart prog; tail -f prog". Separate commands with a
single semicolon; they will be executed in order as you would

3.0a4 (2008-01-30)

- 3.0a3 broke Python 2.3 backwards compatibility.

- On Debian Sarge, one user reported that a call to
options.mktempfile would fail with an "[Errno 9] Bad file
descriptor" at supervisord startup time. I was unable to
reproduce this, but we found a workaround that seemed to work for
him and it's included in this release. See for more information.
Thanks to William Dode.

- The fault ``ALREADY_TERMINATED`` has been removed. It was only raised by
supervisor.sendProcessStdin(). That method now returns ``NOT_RUNNING``
for parity with the other methods. (Mike Naberezny)

- The fault TIMED_OUT has been removed. It was not used.

- Supervisor now depends on meld3 0.6.4, which does not compile its
C extensions by default, so there is no more need to faff around
with NO_MELD3_EXTENSION_MODULES during installation if you don't
have a C compiler or the Python development libraries on your

- Instead of making a user root around for the sample.conf file,
provide a convenience command "echo_supervisord_conf", which he can
use to echo the sample.conf to his terminal (and redirect to a file
appropriately). This is a new user convenience (especially one who
has no Python experience).

- Added ``numprocs_start`` config option to ``[program:x]`` and
``[eventlistener:x]`` sections. This is an offset used to compute
the first integer that ``numprocs`` will begin to start from.
Contributed by Antonio Beamud Montero.

- Added capability for ``[include]`` config section to config format.
This section must contain a single key "files", which must name a
space-separated list of file globs that will be included in
supervisor's configuration. Contributed by Ian Bicking.

- Invoking the ``reload`` supervisorctl command could trigger a bug in
supervisord which caused it to crash. See . Thanks to William Dode for
a bug report.

- The ``pidproxy`` script was made into a console script.

- The ``password`` value in both the ``[inet_http_server]`` and
``[unix_http_server]`` sections can now optionally be specified as a SHA
hexdigest instead of as cleartext. Values prefixed with ``{SHA}`` will be
considered SHA hex digests. To encrypt a password to a form suitable for
pasting into the configuration file using Python, do, e.g.::

>>> import sha
>>> '{SHA}' +'thepassword').hexdigest()

- The subtypes of the events PROCESS_STATE_CHANGE (and
PROCESS_STATE_CHANGE itself) have been removed, replaced with a
simpler set of PROCESS_STATE subscribable event types.

The new event types are:

PROCESS_STATE # abstract













All process state changes have at least "processname",
"groupname", and "from_state" (the name of the previous state) in
their serializations.

PROCESS_STATE_EXITED additionaly has "expected" (1 or 0) and "pid"
(the process id) in its serialization.

PROCESS_STATE_STOPPED additionally have "pid" in their

their serialization (initially "0", bumped +1 each time a start
retry happens).

- Remove documentation from README.txt, point people to .

- The eventlistener request/response protocol has changed. OK/FAIL
must now be wrapped in a RESULT envelope so we can use it for more
specialized communications.

Previously, to signify success, an event listener would write the string
``OK\n`` to its stdout. To signify that the event was seen but couldn't
be handled by the listener and should be rebuffered, an event listener
would write the string ``FAIL\n`` to its stdout.

In the new protocol, the listener must write the string::

RESULT {resultlen}\n{result}

For example, to signify OK::


To signify FAIL::


See the scripts/ script for an example.

- To provide a hook point for custom results returned from event
handlers (see above) the [eventlistener:x] configuration sections
now accept a "result_handler=" parameter,
e.g. "result_handler=supervisor.dispatchers:default_handler" (the
default) or "handler=mypackage:myhandler". The keys are pkgutil
"entry point" specifications (importable Python function names).
Result handlers must be callables which accept two arguments: one
named "event" which represents the event, and the other named
"result", which represents the listener's result. A result
handler either executes successfully or raises an exception. If
it raises a supervisor.dispatchers.RejectEvent exception, the
event will be rebuffered, and the eventhandler will be placed back
into the ACKNOWLEDGED state. If it raises any other exception,
the event handler will be placed in the UNKNOWN state. If it does
not raise any exception, the event is considered successfully
processed. A result handler's return value is ignored. Writing a
result handler is a "in case of emergency break glass" sort of
thing, it is not something to be used for arbitrary business code.
In particular, handlers *must not block* for any appreciable
amount of time.

The standard eventlistener result handler
(supervisor.dispatchers:default_handler) does nothing if it receives an
"OK" and will raise a supervisor.dispatchers.RejectEvent exception if it
receives any other value.

- Supervisord now emits TICK events, which happen every N seconds.
Three types of TICK events are available: TICK_5 (every five
seconds), TICK_60 (every minute), TICK_3600 (every hour). Event
listeners may subscribe to one of these types of events to perform
every-so-often processing. TICK events are subtypes of the EVENT

- Get rid of OSX platform-specific memory monitor and replace with, which works on both Linux and Mac OS. This script is
now a console script named "memmon".

- Allow "web handler" (the handler which receives http requests from
browsers visiting the web UI of supervisor) to deal with POST requests.

- RPC interface methods stopProcess(), stopProcessGroup(), and
stopAllProcesses() now take an optional "wait" argument that defaults
to True for parity with the start methods.

3.0a3 (2007-10-02)

- Supervisorctl now reports a better error message when the main supervisor
XML-RPC namespace is not registered. Thanks to Mike Orr for reporting
this. (Mike Naberezny)

- Create ``scripts`` directory within supervisor package, move
```` there, and place sample event listener and comm event
programs within the directory.

- When an event notification is buffered (either because a listener rejected
it or because all listeners were busy when we attempted to send it
originally), we now rebuffer it in a way that will result in it being
retried earlier than it used to be.

- When a listener process exits (unexpectedly) before transitioning from the
BUSY state, rebuffer the event that was being processed.

- supervisorctl ``tail`` command now accepts a trailing specifier: ``stderr``
or ``stdout``, which respectively, allow a user to tail the stderr or
stdout of the named process. When this specifier is not provided, tail
defaults to stdout.

- supervisor ``clear`` command now clears both stderr and stdout logs for the
given process.

- When a process encounters a spawn error as a result of a failed execve or
when it cannot setuid to a given uid, it now puts this info into the
process' stderr log rather than its stdout log.

- The event listener protocol header now contains the ``server`` identifier,
the ``pool`` that the event emanated from, and the ``poolserial`` as well
as the values it previously contained (version, event name, serial, and
length). The server identifier is taken from the config file options value
``identifier``, the ``pool`` value is the name of the listener pool that
this event emanates from, and the ``poolserial`` is a serial number
assigned to the event local to the pool that is processing it.

- The event listener protocol header is now a sequence of key-value
pairs rather than a list of positional values. Previously, a
representative header looked like::


Now it looks like::

ver:3.0 server:supervisor serial:21 ...

- Specific event payload serializations have changed. All event
types that deal with processes now include the pid of the process
that the event is describing. In event serialization "header"
values, we've removed the space between the header name and the
value and headers are now separated by a space instead of a line
feed. The names of keys in all event types have had underscores

- Abandon the use of the Python stdlib ``logging`` module for speed
and cleanliness purposes. We've rolled our own.

- Fix crash on start if AUTO logging is used with a max_bytes of
zero for a process.

- Improve process communication event performance.

- The process config parameters ``stdout_capturefile`` and
``stderr_capturefile`` are no longer valid. They have been replaced with
the ``stdout_capture_maxbytes`` and ``stderr_capture_maxbytes`` parameters,
which are meant to be suffix-multiplied integers. They both default to
zero. When they are zero, process communication event capturing is not
performed. When either is nonzero, the value represents the maximum number
of bytes that will be captured between process event start and end tags.
This change was to support the fact that we no longer keep capture data in
a separate file, we just use a FIFO in RAM to maintain capture info. For
users whom don't care about process communication events, or whom haven't
changed the defaults for ``stdout_capturefile`` or ``stderr_capturefile``,
they needn't do anything to their configurations to deal with this change.

- Log message levels have been normalized. In particular, process
stdin/stdout is now logged at ``debug`` level rather than at ``trace``
level (``trace`` level is now reserved for output useful typically for
debugging supervisor itself). See "Supervisor Log Levels" in the
documentation for more info.

- When an event is rebuffered (because all listeners are busy or a
listener rejected the event), the rebuffered event is now inserted
in the head of the listener event queue. This doesn't guarantee
event emission in natural ordering, because if a listener rejects
an event or dies while it's processing an event, it can take an
arbitrary amount of time for the event to be rebuffered, and other
events may be processed in the meantime. But if pool listeners
never reject an event or don't die while processing an event, this
guarantees that events will be emitted in the order that they were
received because if all listeners are busy, the rebuffered event
will be tried again "first" on the next go-around.

- Removed EVENT_BUFFER_OVERFLOW event type.

- The supervisorctl xmlrpc proxy can now communicate with
supervisord using a persistent HTTP connection.

- A new module "supervisor.childutils" was added. This module
provides utilities for Python scripts which act as children of
supervisord. Most notably, it contains an API method
"getRPCInterface" allows you to obtain an xmlrpxlib ServerProxy
that is willing to communicate with the parent supervisor. It
also contains utility functions that allow for parsing of
supervisor event listener protocol headers. A pair of scripts
( and were added to the script
directory that serve as examples about how to use the childutils

- A new envvar is added to child process environments:
SUPERVISOR_SERVER_URL. This contains the server URL for the
supervisord running the child.

- An ``OK`` URL was added at ``/ok.html`` which just returns the string
``OK`` (can be used for up checks or speed checks via plain-old-HTTP).

- An additional command-line option ``--profile_options`` is accepted
by the supervisord script for developer use::

supervisord -n -c sample.conf --profile_options=cumulative,calls

The values are sort_stats options that can be passed to the
standard Python profiler's PStats sort_stats method.

When you exit supervisor, it will print Python profiling output to

- If cElementTree is installed in the Python used to invoke
supervisor, an alternate (faster, by about 2X) XML parser will be
used to parse XML-RPC request bodies. cElementTree was added as
an "extras_require" option in

- Added the ability to start, stop, and restart process groups to
supervisorctl. To start a group, use ``start groupname:*``. To start
multiple groups, use ``start groupname1:* groupname2:*``. Equivalent
commands work for "stop" and "restart". You can mix and match short
processnames, fullly-specified group:process names, and groupsplats on the
same line for any of these commands.

- Added ``directory`` option to process config. If you set this
option, supervisor will chdir to this directory before executing
the child program (and thus it will be the child's cwd).

- Added ``umask`` option to process config. If you set this option,
supervisor will set the umask of the child program. (Thanks to
Ian Bicking for the suggestion).

- A pair of scripts ```` and ```
have been added to the scripts directory. If they are used together as
described in their comments, processes which are consuming "too much"
memory will be restarted. The ``eventgen`` script only works on OSX (my
main development platform) but it should be trivially generalizable to
other operating systems.

- The long form ``--configuration`` (-c) command line option for
supervisord was broken. Reported by Mike Orr. (Mike Naberezny)

- New log level: BLAT (blather). We log all
supervisor-internal-related debugging info here. Thanks to Mike
Orr for the suggestion.

- We now allow supervisor to listen on both a UNIX domain socket and an inet
socket instead of making them mutually exclusive. As a result, the options
"http_port", "http_username", "http_password", "sockchmod" and "sockchown"
are no longer part of the ``[supervisord]`` section configuration. These
have been supplanted by two other sections: ``[unix_http_server]`` and
``[inet_http_server]``. You'll need to insert one or the other (depending
on whether you want to listen on a UNIX domain socket or a TCP socket
respectively) or both into your supervisord.conf file. These sections have
their own options (where applicable) for port, username, password, chmod,
and chown. See README.txt for more information about these sections.

- All supervisord command-line options related to "http_port",
"http_username", "http_password", "sockchmod" and "sockchown" have
been removed (see above point for rationale).

- The option that *used* to be ``sockchown`` within the ``[supervisord]``
section (and is now named ``chown`` within the ``[unix_http_server]``
section) used to accept a dot-separated value. The separator
now must be a colon ":", e.g. "user:group". Unices allow for dots in
usernames, so this change is a bugfix. Thanks to Ian Bicking for the bug

- If a '-c' option is not specified on the command line, both supervisord and
supervisorctl will search for one in the paths ``./supervisord.conf`` ,
``./etc/supervisord.conf`` (relative to the current working dir when
supervisord or supervisorctl is invoked) or in ``/etc/supervisord.conf``
(the old default path). These paths are searched in order, and supervisord
and supervisorctl will use the first one found. If none are found,
supervisor will fail to start.

- The Python string expression ``%(here)s`` (referring to the directory in
which the the configuration file was found) can be used within the
following sections/options within the config file::


- The ``--environment`` aka ``-b`` option was removed from the list of
available command-line switches to supervisord (use "A=1 B=2
bin/supervisord" instead).

- If the socket filename (the tail-end of the unix:// URL) was
longer than 64 characters, supervisorctl would fail with an
encoding error at startup.

- The ``identifier`` command-line argument was not functional.

- Fixed (bad error
message in supervisorctl when program command not found on PATH).

- Some child processes may not have been shut down properly at
supervisor shutdown time.

- Move to ZPL-derived (but not ZPL) license availble from; it's slightly less restrictive
than the ZPL (no servicemark clause).

- Spurious errors related to unclosed files ("bad file descriptor",
typically) were evident at supervisord "reload" time (when using
the "reload" command from supervisorctl).

- We no longer bundle ez_setup to bootstrap setuptools installation.

3.0a2 (2007-08-24)

- Fixed the README.txt example for defining the supervisor RPC
interface in the configuration file. Thanks to Drew Perttula.

- Fixed a bug where process communication events would not have the
proper payload if the payload data was very short.

- when supervisord attempted to kill a process with SIGKILL after
the process was not killed within "stopwaitsecs" using a "normal"
kill signal, supervisord would crash with an improper
AssertionError. Thanks to Calvin Hendryx-Parker.

- On Linux, Supervisor would consume too much CPU in an effective
"busywait" between the time a subprocess exited and the time at
which supervisor was notified of its exit status. Thanks to Drew

- RPC interface behavior change: if the RPC method
"sendProcessStdin" is called against a process that has closed its
stdin file descriptor (e.g. it has done the equivalent of
"sys.stdin.close(); os.close(0)"), we return a NO_FILE fault
instead of accepting the data.

- Changed the semantics of the process configuration ``autorestart``
parameter with respect to processes which move between the RUNNING and
EXITED state. ``autorestart`` was previously a boolean. Now it's a
trinary, accepting one of ``false``, ``unexpected``, or ``true``. If it's
``false``, a process will never be automatically restarted from the EXITED
state. If it's ``unexpected``, a process that enters the EXITED state will
be automatically restarted if it exited with an exit code that was not
named in the process config's ``exitcodes`` list. If it's ``true``, a
process that enters the EXITED state will be automatically restarted
unconditionally. The default is now ``unexpected`` (it was previously
``true``). The readdition of this feature is a reversion of the behavior
change note in the changelog notes for 3.0a1 that asserted we never cared
about the process' exit status when determining whether to restart it or

- develop (and presumably install) would fail under Python
2.3.3, because setuptools attempted to import ``splituser`` from urllib2,
and it didn't exist.

- It's now possible to use `` install`` and `` develop`` on
systems which do not have a C compiler if you set the environment variable
"NO_MELD3_EXTENSION_MODULES=1" in the shell in which you invoke these
commands (versions of meld3 > 0.6.1 respect this envvar and do not try to
compile optional C extensions when it's set).

- The test suite would fail on Python versions <= 2.3.3 because
the "assertTrue" and "assertFalse" methods of unittest.TestCase
didn't exist in those versions.

- The ``supervisorctl`` and ``supervisord`` wrapper scripts were disused in
favor of using setuptools' ``console_scripts`` entry point settings.

- Documentation files and the sample configuration file are put into
the generated supervisor egg's ``doc`` directory.

- Using the web interface would cause fairly dramatic memory
leakage. We now require a version of meld3 that does not appear
to leak memory from its C extensions (0.6.3).

3.0a1 (2007-08-16)

- Default config file comment documented 10 secs as default for ``startsecs``
value in process config, in reality it was 1 sec. Thanks to Christoph

- Make note of subprocess environment behavior in README.txt.
Thanks to Christoph Zwerschke.

- New "strip_ansi" config file option attempts to strip ANSI escape
sequences from logs for smaller/more readable logs (submitted by
Mike Naberezny).

- The XML-RPC method supervisor.getVersion() has been renamed for
clarity to supervisor.getAPIVersion(). The old name is aliased
for compatibility but is deprecated and will be removed in a
future version (Mike Naberezny).

- Improved web interface styling (Mike Naberezny, Derek DeVries)

- The XML-RPC method supervisor.startProcess() now checks that
the file exists and is executable (Mike Naberezny).

- Two environment variables, "SUPERVISOR_PROCESS_NAME" and
"SUPERVISOR_PROCESS_GROUP" are set in the environment of child
processes, representing the name of the process and group in
supervisor's configuration.

- Process state map change: a process may now move directly from the
STARTING state to the STOPPING state (as a result of a stop

- Behavior change: if ``autorestart`` is true, even if a process exits with
an "expected" exit code, it will still be restarted. In the immediately
prior release of supervisor, this was true anyway, and no one complained,
so we're going to consider that the "officially correct" behavior from now

- Supervisor now logs subprocess stdout and stderr independently.
The old program config keys "logfile", "logfile_backups" and
"logfile_maxbytes" are superseded by "stdout_logfile",
"stdout_logfile_backups", and "stdout_logfile_maxbytes". Added
keys include "stderr_logfile", "stderr_logfile_backups", and
"stderr_logfile_maxbytes". An additional "redirect_stderr" key is
used to cause program stderr output to be sent to its stdin
channel. The keys "log_stderr" and "log_stdout" have been

- ``[program:x]`` config file sections now represent "homgeneous process
groups" instead of single processes. A "numprocs" key in the section
represents the number of processes that are in the group. A "process_name"
key in the section allows composition of the each process' name within the
homogeneous group.

- A new kind of config file section, ``[group:x]`` now exists, allowing users
to group heterogeneous processes together into a process group that can be
controlled as a unit from a client.

- Supervisord now emits "events" at certain points in its normal
operation. These events include supervisor state change events,
process state change events, and "process communication events".

- A new kind of config file section ``[eventlistener:x]`` now exists. Each
section represents an "event listener pool", which is a special kind of
homogeneous process group. Each process in the pool is meant to receive
supervisor "events" via its stdin and perform some notification (e.g. send
a mail, log, make an http request, etc.)

- Supervisord can now capture data between special tokens in
subprocess stdout/stderr output and emit a "process communications
event" as a result.

- Supervisor's XML-RPC interface may be extended arbitrarily by programmers.
Additional top-level namespace XML-RPC interfaces can be added using the
``[rpcinterface:foo]`` declaration in the configuration file.

- New ``supervisor``-namespace XML-RPC methods have been added:
getAPIVersion (returns the XML-RPC API version, the older
"getVersion" is now deprecated), "startProcessGroup" (starts all
processes in a supervisor process group), "stopProcessGroup"
(stops all processes in a supervisor process group), and
"sendProcessStdin" (sends data to a process' stdin file

- ``supervisor``-namespace XML-RPC methods which previously accepted
ony a process name as "name" (startProcess, stopProcess,
getProcessInfo, readProcessLog, tailProcessLog, and
clearProcessLog) now accept a "name" which may contain both the
process name and the process group name in the form
``groupname:procname``. For backwards compatibility purposes,
"simple" names will also be accepted but will be expanded
internally (e.g. if "foo" is sent as a name, it will be expanded
to "foo:foo", representing the foo process within the foo process

- 2.X versions of supervisorctl will work against supervisor 3.0
servers in a degraded fashion, but 3.X versions of supervisorctl
will not work at all against supervisor 2.X servers.

2.2b1 (2007-03-31)

- Individual program configuration sections can now specify an

- Added a 'version' command to supervisorctl. This returns the
version of the supervisor2 package which the remote supervisord
process is using.

2.1 (2007-03-17)

- When supervisord was invoked more than once, and its configuration
was set up to use a UNIX domain socket as the HTTP server, the
socket file would be erased in error. The symptom of this was
that a subsequent invocation of supervisorctl could not find the
socket file, so the process could not be controlled (it and all of
its subprocesses would need to be killed by hand).

- Close subprocess file descriptors properly when a subprocess exits
or otherwise dies. This should result in fewer "too many open
files to spawn foo" messages when supervisor is left up for long
periods of time.

- When a process was not killable with a "normal" signal at shutdown
time, too many "INFO: waiting for x to die" messages would be sent
to the log until we ended up killing the process with a SIGKILL.
Now a maximum of one every three seconds is sent up until SIGKILL
time. Thanks to Ian Bicking.

- Add an assertion: we never want to try to marshal None to XML-RPC
callers. Issue 223 in the collector from vgatto indicates that
somehow a supervisor XML-RPC method is returning None (which
should never happen), but I cannot identify how. Maybe the
assertion will give us more clues if it happens again.

- Supervisor would crash when run under Python 2.5 because the
xmlrpclib.Transport class in Python 2.5 changed in a
backward-incompatible way. Thanks to Eric Westra for the bug
report and a fix.

- Tests now pass under Python 2.5.

- Better supervisorctl reporting on stop requests that have a FAILED

- Removed duplicated code (readLog/readMainLog), thanks to Mike

- Added tailProcessLog command to the XML-RPC API. It provides a
more efficient way to tail logs than readProcessLog(). Use
readProcessLog() to read chunks and tailProcessLog() to tail.
(thanks to Mike Naberezny).

2.1b1 (2006-08-30)

- "supervisord -h" and "supervisorctl -h" did not work (traceback
instead of showing help view (thanks to Damjan from Macedonia for
the bug report).

- Processes which started successfully after failing to start
initially are no longer reported in BACKOFF state once they are
started successfully (thanks to Damjan from Macdonia for the bug

- Add new 'maintail' command to supervisorctl shell, which allows
you to tail the 'main' supervisor log. This uses a new
readMainLog xmlrpc API.

- Various process-state-transition related changes, all internal.
README.txt updated with new state transition map.

- startProcess and startAllProcesses xmlrpc APIs changed: instead of
accepting a timeout integer, these accept a wait boolean (timeout
is implied by process' "startsecs" configuration). If wait is
False, do not wait for startsecs.

Known issues:

- Code does not match state transition map. Processes which are
configured as autorestarting which start "successfully" but
subsequently die after 'startsecs' go through the transitions
RUNNING -> BACKOFF -> STARTING instead of the correct transitions
RUNNING -> EXITED -> STARTING. This has no real negative effect,
but should be fixed for correctness.

2.0 (2006-08-30)

- pidfile written in daemon mode had incorrect pid.

- supervisorctl: tail (non -f) did not pass through proper error
messages when supplied by the server.

- Log signal name used to kill processes at debug level.

- supervisorctl "tail -f" didn't work with supervisorctl sections
configured with an absolute unix:// URL

- New "environment" config file option allows you to add environment
variable values to supervisord environment from config file.

2.0b1 (2006-07-12)

- Fundamental rewrite based on 1.0.7, use distutils (only) for
installation, use ConfigParser rather than ZConfig, use HTTP for
wire protocol, web interface, less lies in supervisorctl.

1.0.7 (2006-07-11)

- Don't log a waitpid error if the error value is "no children".

- Use select() against child file descriptor pipes and bump up select
timeout appropriately.

1.0.6 (2005-11-20)

- Various tweaks to make run more effectively on Mac OS X
(including fixing tests to run there, no more "error reading
from fd XXX" in logtail output, reduced disk/CPU usage as a
result of not writing to log file unnecessarily on Mac OS).

1.0.5 (2004-07-29)

- Short description: In previous releases, managed programs that
created voluminous stdout/stderr output could run more slowly
than usual when invoked under supervisor, now they do not.

Long description: The supervisord manages child output by
polling pipes related to child process stderr/stdout. Polling
operations are performed in the mainloop, which also performs a
'select' on the filedescriptor(s) related to client/server
operations. In prior releases, the select timeout was set to 2
seconds. This release changes the timeout to 1/10th of a second
in order to keep up with client stdout/stderr output.

Gory description: On Linux, at least, there is a pipe buffer
size fixed by the kernel of somewhere between 512 - 4096 bytes;
when a child process writes enough data to fill the pipe buffer,
it will block on further stdout/stderr output until supervisord
comes along and clears out the buffer by reading bytes from the
pipe within the mainloop. We now clear these buffers much more
quickly than we did before due to the increased frequency of
buffer reads in the mainloop; the timeout value of 1/10th of a
second seems to be fast enough to clear out the buffers of child
process pipes when managing programs on even a very fast system
while still enabling the supervisord process to be in a sleeping
state for most of the time.

1.0.4 or "Alpha 4" (2004-06-30)

- Forgot to update version tag in, so the supervisor version
in a3 is listed as "1.0.1", where it should be "1.0.3". a4 will be
listed as "1.0.4'.

- Instead of preventing a process from starting if setuid() can't
be called (if supervisord is run as nonroot, for example), just log
the error and proceed.

1.0.3 or "Alpha 3" (2004-05-26)

- The daemon could chew up a lot of CPU time trying to select()
on real files (I didn't know select() failed to block when a file
is at EOF). Fixed by polling instead of using select().

- Processes could "leak" and become zombies due to a bug in
reaping dead children.

- supervisord now defaults to daemonizing itself.

- 'daemon' config file option and -d/--daemon command-line option
removed from supervisord acceptable options. In place of these
options, we now have a 'nodaemon' config file option and a
-n/--nodaemon command-line option.

- logtail now works.

- pidproxy changed slightly to reap children synchronously.

- in alpha2 changelist, supervisord was reported to have a
"noauth" command-line option. This was not accurate. The way
to turn off auth on the server is to disinclude the "passwdfile"
config file option from the server config file. The client
however does indeed still have a noauth option, which prevents
it from ever attempting to send authentication credentials to

- ZPL license added for ZConfig to LICENSE.txt

1.0.2 or "Alpha 2" (Unreleased)

- supervisorctl and supervisord no longer need to run on the same machine
due to the addition of internet socket support.

- supervisorctl and supervisord no longer share a common configuration
file format.

- supervisorctl now uses a persistent connection to supervisord
(as opposed to creating a fresh connection for each command).

- SRP (Secure Remote Password) authentication is now a supported form
of access control for supervisord. In supervisorctl interactive mode,
by default, users will be asked for credentials when attempting to
talk to a supervisord that requires SRP authentication.

- supervisord has a new command-line option and configuration file
option for specifying "noauth" mode, which signifies that it
should not require authentication from clients.

- supervisorctl has a new command-line option and configuration
option for specifying "noauth" mode, which signifies that it
should never attempt to send authentication info to servers.

- supervisorctl has new commands: open: opens a connection to a new
supervisord; close: closes the current connection.

- supervisorctl's "logtail" command now retrieves log data from
supervisord's log file remotely (as opposed to reading it
directly from a common filesystem). It also no longer emulates
"tail -f", it just returns <n> lines of the server's log file.

- The supervisord/supervisorctl wire protocol now has protocol versioning
and is documented in "protocol.txt".

- "configfile" command-line override -C changed to -c

- top-level section name for supervisor schema changed to 'supervisord'
from 'supervisor'

- Added 'pidproxy' shim program.

Known issues in alpha 2:

- If supervisorctl loses a connection to a supervisord or if the
remote supervisord crashes or shuts down unexpectedly, it is
possible that any supervisorctl talking to it will "hang"
indefinitely waiting for data. Pressing Ctrl-C will allow you
to restart supervisorctl.

- Only one supervisorctl process may talk to a given supervisord
process at a time. If two supervisorctl processes attempt to talk
to the same supervisord process, one will "win" and the other will
be disconnected.

- Sometimes if a pidproxy is used to start a program, the pidproxy
program itself will "leak".

1.0.0 or "Alpha 1" (Unreleased)

Initial release.

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