Class: Krikri::Activity

Inherits:
ActiveRecord::Base
  • Object
show all
Defined in:
app/models/krikri/activity.rb

Overview

Activity wraps code execution with metadata about when it ran, which agents were responsible. It is designed to run a variety of different jobs, and its #run method is passed a block that performs the actual work. It records the start and end time of the job run, and provides the name of the agent to whomever needs it, but it does not care what kind of activity it is – harvest, enrichment, etc.

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#agent ⇒ String

Returns a string representing the Krikri::SoftwareAgent responsible for the activity.

Returns:

  • (String) —

    a string representing the Krikri::SoftwareAgent responsible for the activity.



21
 
# File 'app/models/krikri/activity.rb', line 21

validate :agent_must_be_a_software_agent

#end_time ⇒ DateTime

Returns a datestamp marking the activity’s competion.

Returns:

  • (DateTime) —

    a datestamp marking the activity’s competion



21
 
# File 'app/models/krikri/activity.rb', line 21

validate :agent_must_be_a_software_agent

#opts ⇒ JSON

Returns the options to pass to the #agent class when running the activity.

Returns:

  • (JSON) —

    the options to pass to the #agent class when running the activity



21
 
# File 'app/models/krikri/activity.rb', line 21

validate :agent_must_be_a_software_agent

#start_time ⇒ DateTime

Returns a datestamp marking the activity’s start.

Returns:

  • (DateTime) —

    a datestamp marking the activity’s start



21
 
# File 'app/models/krikri/activity.rb', line 21

validate :agent_must_be_a_software_agent

Instance Method Details

#agent_instance ⇒ Agent

Instantiates and returns an instance of the Agent class with the values in opts.

Returns:

  • (Agent) —

    an instance of the class stored in Agent



81
82
83
 
# File 'app/models/krikri/activity.rb', line 81

def agent_instance
  @agent_instance ||= agent.constantize.new(parsed_opts)
end

#agent_must_be_a_software_agent ⇒ Object 



23
24
25
26
 
# File 'app/models/krikri/activity.rb', line 23

def agent_must_be_a_software_agent
  errors.add(:agent, 'does not represent a SoftwareAgent') unless
    agent.constantize < Krikri::SoftwareAgent
end

#ended? ⇒ Boolean

Indicates whether the activity has ended. Does not distinguish between successful and failed completion states.

Returns:

  • (Boolean) —

    ‘true` if the activity has been marked as ended, else `false`



72
73
74
 
# File 'app/models/krikri/activity.rb', line 72

def ended?
  !self.end_time.nil?
end

#entities ⇒ Enumerator

Return an Enumerator of entities (e.g. aggregations or original records) that have been affected by this activity.

The kind of object that is returned depends on the EntityBehavior class that is associated with the SoftwareAgent that is represented by the Activity’s ‘agent’ field.

Returns:

  • (Enumerator) —

    Objects



126
127
128
 
# File 'app/models/krikri/activity.rb', line 126

def entities
  agent_instance.entity_behavior.entities(self)
end

#entity_uris ⇒ Enumerator

Return an Enumerator of URI strings of entities (e.g. aggregations or original records) that pertain to this activity

Returns:

  • (Enumerator) —

    URI strings



109
110
111
112
113
114
115
 
# File 'app/models/krikri/activity.rb', line 109

def entity_uris
  activity_uri = RDF::URI(rdf_subject)  # This activity's LDP URI
  query = Krikri::ProvenanceQueryClient.find_by_activity(activity_uri)
  query.each_solution.lazy.map do |s|
    s.record.to_s
  end
end

#parsed_opts ⇒ Object 



85
86
87
 
# File 'app/models/krikri/activity.rb', line 85

def parsed_opts
  JSON.parse(opts, symbolize_names: true)
end

#rdf_subject ⇒ RDF::URI Also known as: to_term

Returns the uri for this activity.

Returns:

  • (RDF::URI) —

    the uri for this activity



91
92
93
94
 
# File 'app/models/krikri/activity.rb', line 91

def rdf_subject
  RDF::URI(Krikri::Settings['marmotta']['ldp']) /
    Krikri::Settings['prov']['activity'] / id.to_s
end

#run ⇒ Object

Runs the block, setting the start and end time of the run. The given block is passed an instance of the agent, and a URI representing this Activity.

Handles logging of activity start/stop and failure states.

Raises:

  • (RuntimeError) —

    re-raises logged errors on Activity failure



46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
 
# File 'app/models/krikri/activity.rb', line 46

def run
  if block_given?
    update_attribute(:end_time, nil) if ended?
    Krikri::Logger
      .log(:info, "Activity #{agent.constantize}-#{id} is running")
    set_start_time
    begin
      yield agent_instance, rdf_subject
    rescue => e
      Krikri::Logger.log(:error, "Error performing Activity: #{id}\n" \
                                 "#{e.message}\n#{e.backtrace}")
      raise e
    ensure
      set_end_time
      Krikri::Logger
        .log(:info, "Activity #{agent.constantize}-#{id} is done")
    end
  end
end

#set_end_time ⇒ Object 



32
33
34
35
36
37
 
# File 'app/models/krikri/activity.rb', line 32

def set_end_time
  now = DateTime.now.utc
  fail 'Start time must exist and be before now to set an end time' unless
    self[:start_time] && (self[:start_time] <= now)
  update_attribute(:end_time, now)
end

#set_start_time ⇒ Object 



28
29
30
 
# File 'app/models/krikri/activity.rb', line 28

def set_start_time
  update_attribute(:start_time, DateTime.now.utc)
end

#to_s ⇒ String

Returns a string reprerestation of the activity.

Returns:

  • (String) —

    a string reprerestation of the activity



100
101
102
 
# File 'app/models/krikri/activity.rb', line 100

def to_s
  inspect.to_s
end