Module: Locd::Agent::System

Included in:
Proxy, RotateLogs
Defined in:
lib/locd/agent/system.rb

Overview

Mixin for common stuff that system agents do different.

System agents are specific types of Locd::Agent built in to Loc'd to handle things like proxying HTTP request site (Proxy), rotating logs so they don't get unwieldily (RotaeLogs), and probably more in the future, like serving a site index, API, etc.

System agents are singular - there's only one of each for a Loc'd label namespace, which is set via the configuration, and Loc'd uses that label namespace, together with the each system agent's .label_name, to form the agent's unique label, which is how it finds the system agents.

This was really just to make it simpler by side-stepping how to handle many proxies and log rotators and such because besides the dev/release situation described above I can't really think of any reason you would want to create and manage multiple of each system agent.

As a consequence, Locd::Agent subclasses that mix System in must define a .label_name class method.

Defined Under Namespace

Modules: ClassMethods

Constant Summary collapse

@@classes = 
Hamster::Set.new

Class Method Summary collapse

Class Method Details

.class_for(plist) ⇒ Class<Locd::Agent>?

Find the concrete Locd::Agent subclass (that has mixed in Locd::Agent::System) for a property list.

Parameters:

  • plist (Hash<String, Object>) —

Returns:

  • (Class<Locd::Agent>) —

    If the plist is for one of classes, returns that class.

  • (nil) —

    If the plist is:

    1. Not a system plist (see plist?)

    2. If none of classes claim it (via their .plist? method).

      Though, really, this one shouldn't happen except in weird version switching situations maybe or something.



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# File 'lib/locd/agent/system.rb', line 107

def self.class_for plist
  return nil unless plist?( plist )
  
  classes.to_a.find_bounded( max: 1 ) { |cls| cls.plist? plist }.first
end

.classes ⇒ Object 



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# File 'lib/locd/agent/system.rb', line 38

def self.classes
  @@classes
end

.included(base) ⇒ Object 



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# File 'lib/locd/agent/system.rb', line 114

def self.included base
  base.extend ClassMethods
  @@classes = @@classes.add base
end

.instance_label?(label) ⇒ Boolean

Note:

We can't tell if a label is a system agent label for any Loc'd instance since the prefix can be configured to anything (via the locd:namespace:label key).

Is an agent label for a system agent of this Loc'd instance?

Returns:

  • (Boolean) 


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# File 'lib/locd/agent/system.rb', line 52

def self.instance_label? label
  label.is_a?( String ) &&
  label.start_with?( "#{ Locd.config[:namespace, :label] }." )
end

.instance_plist?(plist) ⇒ Boolean

Is a plist for a system agent of this Loc'd instance?

Parameters:

  • plist (Hash<String, Object>) —

Returns:

  • (Boolean) —

    true if the plist is for a system agent for this Loc'd instance config.

See Also:



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# File 'lib/locd/agent/system.rb', line 84

def self.instance_plist? plist
  plist?( plist ) && instance_label?( plist[ 'Label' ] )
end

.plist?(plist) ⇒ Boolean

Is the plist for a system agent of any Loc'd instance?

In case it's not obvious, this tests true given plists of system agents of other Loc'd instance configurations besides just this one, which can be useful to weed things out. Maybe.

Parameters:

  • plist (Hash<String, Object>) —

Returns:

  • (Boolean) —

    true if the plist is for a system agent.



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# File 'lib/locd/agent/system.rb', line 69

def self.plist? plist
  plist.dig( Locd.config[:agent, :config_key], 'is_system' ) == true
end