Class: Outpost::Application

Inherits:
Object
  • Object
show all
Defined in:
lib/outpost/application.rb

Overview

This class is the basic structure of an Outpost application. It provides the basic DSL for you to configure the monitoring of your services. Example:

class ExampleSuccess < Outpost::Application
  name "Example"
  using Outpost::Scouts::Http => 'master http server' do
    options :host => 'localhost', :port => 9595
    report :up, :response_code => 200
  end
end

The above example will set templates and every new instance of ExampleSuccess will have the same behavior. But all the methods are available to instances, so it is also possible to create Outpost applications as the following example:

my_outpost = Outpost::Application.new
my_outpost.name = 'Example'

my_outpost.using(Outpost::Scouts::Http => 'master http server') do
  options :host => 'localhost', :port => 9595
  report :up, :response_code => 200
end

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Application

New instance of a Outpost-based class.



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# File 'lib/outpost/application.rb', line 95

def initialize
  @reports     = {}
  @last_status = nil
  @scouts      = Hash.new { |h, k| h[k] = [] }
  @notifiers   = {}
  @name        = self.class.name_template

  # Register scouts
  self.class.scout_templates.each do |template|
    add_scout(template[:scout_description], &template[:block])
  end

  self.class.notifier_templates.each do |template|
    add_notifier(template[:notifier], template[:options])
  end
end

Instance Attribute Details

#last_status ⇒ Object (readonly)

Returns the status of the last service check or nil if it didn’t happen.



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# File 'lib/outpost/application.rb', line 80

def last_status
  @last_status
end

#name ⇒ Object

Reader/setter for the name of this scout



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# File 'lib/outpost/application.rb', line 92

def name
  @name
end

#notifiers ⇒ Object (readonly)

Returns all the registered notifiers.



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# File 'lib/outpost/application.rb', line 89

def notifiers
  @notifiers
end

#reports ⇒ Object (readonly)

Returns a list of Report containing the last results of the last check.



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# File 'lib/outpost/application.rb', line 83

def reports
  @reports
end

#scouts ⇒ Object (readonly)

Returns all the registered scouts.



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# File 'lib/outpost/application.rb', line 86

def scouts
  @scouts
end

Class Method Details

.name(val = nil) ⇒ Object

Set the name of the scout. Can be used by notifiers in order to have a better description of the service in question.

Parameters:

  • name (String, #read) —

    The name to be given to a Outpost-based class.



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# File 'lib/outpost/application.rb', line 73

def name(val=nil)
  @name_template = val if val
  @name_template
end

.name_template ⇒ Object 



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# File 'lib/outpost/application.rb', line 36

def name_template
  @name_template || self.to_s
end

.notifier_templates ⇒ Object 



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# File 'lib/outpost/application.rb', line 32

def notifier_templates
  @notifier_templates || []
end

.notify(notifier, options = {}) ⇒ Object

Register a notifier class in the list of notifications.

Parameters:

  • class (Class, #read) —

    A class that will be used to issue a notification. The class must accept a configuration hash in the constructor and also implement a #notify method that will receive an outpost instance. See Notifiers::Email for an example.

  • options (Hash, #read) (defaults to: {}) —

    Options that will be used to configure the notification class.



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# File 'lib/outpost/application.rb', line 63

def notify(notifier, options={})
  @notifier_templates ||= []
  @notifier_templates << {:notifier => notifier, :options => options}
end

.scout_templates ⇒ Object 



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# File 'lib/outpost/application.rb', line 28

def scout_templates
  @scout_templates || []
end

.using(scout_description) { ... } ⇒ Object

Register a scout in the list of scouts.

Parameters:

  • scout_description (Hash{Scout => String}, #read) —

    A hash containing Scout class as key and its description as a value.

Yields:

  • Block to be evaluated to configure the current Scout.



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# File 'lib/outpost/application.rb', line 46

def using(scout_description, &block)
  @scout_templates ||= []
  @scout_templates << {
    :scout_description => scout_description,
    :block => block
  }
end

Instance Method Details

#add_notifier(notifier_name, options) ⇒ Object

See Also:



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# File 'lib/outpost/application.rb', line 126

def add_notifier(notifier_name, options)
  @notifiers[notifier_name] = options
end

#add_scout(scout_description, &block) ⇒ Object

See Also:



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# File 'lib/outpost/application.rb', line 113

def add_scout(scout_description, &block)
  config = ScoutConfig.new
  config.instance_eval(&block)

  scout_description.each do |scout, description|
    @scouts[scout] << {
      :description => description,
      :config => config
    }
  end
end

#down? ⇒ Boolean

Returns true if the last status is :down

Returns:

  • (Boolean) 


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# File 'lib/outpost/application.rb', line 166

def down?
  @last_status == :down
end

#messages ⇒ Array<String>

Returns the messages of the latest service check.

Returns:

  • (Array<String>) —

    An array containing all report messages.



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# File 'lib/outpost/application.rb', line 173

def messages
  reports.map { |_, r| r.to_s }
end

#notify ⇒ Object

Runs all notifications associated with an Outpost-based class.



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# File 'lib/outpost/application.rb', line 145

def notify
  if reports.any?
    @notifiers.each do |notifier, options|
      # .dup is NOT reliable
      options_copy = Marshal.load(Marshal.dump(options))
      notifier.new(options_copy).notify(self)
    end
  end
end

#run ⇒ Object

Execute all the scouts associated with an Outpost-based class and returns either :up or :down, depending on the results.



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# File 'lib/outpost/application.rb', line 132

def run
  scouts.map do |scout, configurations|
    configurations.each do |options|
      @reports[options[:description]] = run_scout(scout, options)
    end
  end

  statuses = @reports.map { |_, r| r.status }

  @last_status = Report.summarize(statuses)
end

#up? ⇒ Boolean

Returns true if the last status is :up

Returns:

  • (Boolean) 


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# File 'lib/outpost/application.rb', line 156

def up?
  @last_status == :up
end

#warning? ⇒ Boolean

Returns true if the last status is :warning

Returns:

  • (Boolean) 


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# File 'lib/outpost/application.rb', line 161

def warning?
  @last_status == :warning
end