Gafferd is a server able to launch and manage processes. It can be controlled via the HTTP api .


$ gafferd -h
usage: gafferd [-h] [-c CONFIG_FILE] [-p PLUGINS_DIR] [-v] [-vv] [--daemon]
               [--pidfile PIDFILE] [--bind BIND] [--certfile CERTFILE]
               [--keyfile KEYFILE] [--backlog BACKLOG]

Run some watchers.

positional arguments:
  config                configuration file

optional arguments:
  -h, --help            show this help message and exit
                        configuration file
  -p PLUGINS_DIR, --plugins-dir PLUGINS_DIR
                        default plugin dir
  -v                    verbose mode
  -vv                   like verbose mode but output stream too
  --daemon              Start gaffer in the background
  --pidfile PIDFILE
  --bind BIND           default HTTP binding
  --certfile CERTFILE   SSL certificate file for the default binding
  --keyfile KEYFILE     SSL key file for the default binding
  --backlog BACKLOG     default backlog

Config file example

http_endpoints = public

bind =

;create = http://some/url
;proc.dummy.spawn = http://some/otherurl

cmd = ./
;cwd = .
;uid =
;gid =
;detach = false
;shell = false
; flapping format: attempts=2, window=1., retry_in=7., max_retry=5
;flapping = 2, 1., 7., 5
numprocesses = 1
redirect_output = stdout, stderr
; redirect_input  = true
; graceful_timeout = 30

cmd = ./
numprocesses = 1
redirect_output = stdout, stderr
redirect_input  = true


Plugins are a way to enhance the basic gafferd functionality in a custom manner. Plugins allows you to load any gaffer application and site plugins. You can for example use the plugin system to add a simple UI to administrate gaffer using the HTTP interface.

A plugin has the following structure:


A plugin can be discovered by adding one ore more module that expose a class inheriting from gaffer.Plugin. Every plugin file should have a __all__ attribute containing the implemented plugin class. Ex:

from gaffer import Plugin

__all__ = ['DummyPlugin']

from .app import DummyApp

class DummyPlugin(Plugin):
    name = "dummy"
    version = "1.0"
    description = "test"

    def app(self, cfg):
        return DummyApp()

The dummy app here only print some info when started or stopped:

class DummyApp(object):

    def start(self, loop, manager):
        print("start dummy app")

    def stop(sef):
        print("stop dummy")

    def rester(self):
        print("restart dummy")

See the Overview for more infos. You can try it in the example folder:

$ cd examples
$ gafferd -c gaffer.ini -p plugins/

Install plugins

Installing plugins can be done by placing the plugin in the plugin folder. The plugin folder is either set in the setting file using the plugin_dir in the gaffer section or using the -p option of the command line.

The default plugin dir is set to ~/.gafferd/plugins .

Site plugins

Plugins can have “sites” in them, any plugin that exists under the plugins directory with a _site directory, its content will be statically served when hitting /_plugin/[plugin_name]/ url. Those can be added even after the process has started.

Installed plugins that do not contain any Python related content, will automatically be detected as site plugins, and their content will be moved under _site.

Mandatory Plugins

If you rely on some plugins, you can define mandatory plugins using the mandatory attribute of a the plugin class, for example, here is a sample config:

class DummyPlugin(Plugin):
    mandatory = ['somedep']