Configuration

The gofer agent and plugins are configured using ini style configuration files located in /etc/gofer.

Agent Configuration

The agent configuration is specified in: /etc/gofer/agent.conf and through files located in /etc/gofer/conf.d. During startup, gofer first reads agent.conf. Then, reads and merges in values found in the conf.d files.

All configuration files support the following sections and properties:

[management]

Defines agent management properties.

  • enabled - Management is (1=enabled|0=disabled).
  • host - The host (interface) the manager listens on. Defaults to: localhost.
  • port - The port the manager listens on. Defaults to: 5650.

[logging]

This section sets logging properties. Currently, the logging level can be set for each gofer package as follows:

<package>=<level>

The special root package may be used to set the logging level for all packages.

Levels (may be lower case):

  • CRITICAL
  • DEBUG
  • ERROR
  • FATAL
  • INFO
  • WARN
  • WARNING

Gofer packages:

The list of common packages. Set to DEBUG for more information.

  • root - The root logger for the python process. Applies to all packages.
  • gofer - All of gofer.
  • gofer.agent - The agent which includes plugin management and request dispatching.
  • gofer.messaging - All AMQP messaging.
  • gofer.rmi - The RMI request/response protocol and processing.

Examples:

[logging]
gofer.agent=DEBUG
gofer.messaging=DEBUG

[logging]
root=DEBUG

[pam]

  • service - The (optional) service to be used for PAM authentication.

Plugin Descriptors

Each plugin has a configuration located in /etc/gofer/plugins. Plugin descriptors are ini style configuration files that require the following sections and properties:

[main]

Defines basic plugin properties.

  • name - The (optional) plugin name. The basename of the descriptor is used when not specified.

  • plugin - The (optional) fully qualified path to the module to be loaded from the PYTHON path. When plugin is not specified, the plugin is loaded by searching the following directories for a module with the same name as the plugin:

    • /usr/share/gofer/plugins
    • /usr/lib/gofer/plugins
    • /usr/lib64/gofer/plugins
    • /opt/gofer/plugins

  • enabled - The plugin is (1=enabled|=0disabled).

  • threads - The (optional) number of threads for the RMI dispatcher.

  • latency - The (optional) latency (seconds) to be introduced into RMI execution.

  • accept - Accept forwarding list. Comma ‘,’ separated list of plugin names.

  • forward - Forwarding list. Comma ‘,’ separated list of plugin names.

The latency property is intended to be used to create a cancellation window or provide throttling. Adding latency, increases the opportunity for an RMI request to be canceled prior to being started.

[messaging]

  • authenticator - The (optional) fully qualified path to a message Authenticator to be loaded from the PYTHON path.

  • uuid - The agent identity. This value also specifies the queue name.

  • ‘url - The (optional) broker connection URL. No value indicates the plugin should not connect to broker. format: <adapter>+<protocol>://<user>:<password>@<host>:<port>/<virtual-host>, protocol is one of:

    • tcp: non-SSL protocol
    • amqp: non-SSL protocol
    • ssl: SSL protocol
    • amqps: SSL protocol

    The <adapter>, <user>:<password> and /<virtual-host> are optional. See: Messaging Adapters for list of supported adapters.

    The <port> is optional and defaults based on the protocol when not specified:

    • (amqp|tcp) port:5672
    • (amqps|ssl) port:5671

  • cacert - The (optional) SSL CA certificate used to validate the server certificate.

  • clientkey - The (optional) SSL client private key.

  • clientcert - The (optional) SSL client certificate. A (PEM) file may contain both the private key and certificate.

  • host_validation - The (optional) flag indicates SSL host validation should be performed. Default to (1) when not specified.

  • heartbeat - The (optional) AMQP heartbeat in seconds. (default:10).

File extensions just be (.conf|.json).

[model]

  • managed - The model is manged. Default:2

    • 0: Not managed.
    • 1: The queue is declared on attach and bound the the exchange as needed.
    • 2: The queue is declared on attach and bound the the exchange as needed and drained and deleted on explicit detach.

  • queue - The (optional) AMQP queue name. This has precedent over uuid. Format: <exchange>/<queue> where exchange is optional.

  • expiration - The (optional) auto-deleted queue expiration (seconds).

Examples

This example enables messaging and defines the uuid:

[main]
enabled=1

[messaging]
url=qpid+amqp://localhost

[model]
queue=123

This example enables messaging and does not define the uuid. It is expected that the plugin defines an @load decorated method/function that provides the url and queue:

[main]
enabled=1
accept=*

This example does not enable messaging for this plugin. This would be done when the plugin does not need to specify an additional identity. This example also specifies a user defined sections to be used by the plugin:

[main]
enabled=1

[messaging]
url=qpid+amqp://localhost

[model]
queue=123

[foobar]
timeout=100

However, additional user defined sections and properties are supported and made available to the plugin(s) as follows:

from gofer.agent.plugin import Plugin
...
class MyPlugin:
  ...
  def mymethod(self):
      cfg = Plugin.find(__name__).cfg()
      timeout = cfg.foobar.timeout
      ...