|
require 'rturk'
module Agents
class HumanTaskAgent < Agent
default_schedule "every_10m"
description <<-MD
You can use a HumanTaskAgent to create Human Intelligence Tasks (HITs) on Mechanical Turk.
HITs can be created in response to events, or on a schedule. Set `trigger_on` to either `schedule` or `event`.
# Schedule
The schedule of this Agent is how often it should check for completed HITs, __NOT__ how often to submit one. To configure how often a new HIT
should be submitted when in `schedule` mode, set `submission_period` to a number of hours.
# Example
If created with an event, all HIT fields can contain interpolated values via [JSONPaths](http://goessner.net/articles/JsonPath/) placed between < and > characters.
For example, if the incoming event was a Twitter event, you could make a HITT to rate its sentiment like this:
{
"expected_receive_period_in_days": 2,
"trigger_on": "event",
"hit": {
"assignments": 1,
"title": "Sentiment evaluation",
"description": "Please rate the sentiment of this message: '<$.message>'",
"reward": 0.05,
"lifetime_in_seconds": "3600",
"questions": [
{
"type": "selection",
"key": "sentiment",
"name": "Sentiment",
"required": "true",
"question": "Please select the best sentiment value:",
"selections": [
{ "key": "happy", "text": "Happy" },
{ "key": "sad", "text": "Sad" },
{ "key": "neutral", "text": "Neutral" }
]
},
{
"type": "free_text",
"key": "feedback",
"name": "Have any feedback for us?",
"required": "false",
"question": "Feedback",
"default": "Type here...",
"min_length": "2",
"max_length": "2000"
}
]
}
}
As you can see, you configure the created HIT with the `hit` option. Required fields are `title`, which is the
title of the created HIT, `description`, which is the description of the HIT, and `questions` which is an array of
questions. Questions can be of `type` _selection_ or _free\\_text_. Both types require the `key`, `name`, `required`,
`type`, and `question` configuration options. Additionally, _selection_ requires a `selections` array of options, each of
which contain `key` and `text`. For _free\\_text_, the special configuration options are all optional, and are
`default`, `min_length`, and `max_length`.
# Combining answers
There are a couple of ways to combine HITs that have multiple `assignments`, all of which involve setting `combination_mode` at the top level.
## Taking the majority
Option 1: if all of your `questions` are of `type` _selection_, you can set `combination_mode` to `take_majority`.
This will cause the Agent to automatically select the majority vote for each question across all `assignments` and return it as `majority_answer`.
If all selections are numeric, an `average_answer` will also be generated.
Option 2: you can have the Agent ask additional human workers to rank the `assignments` and return the most highly ranked answer.
To do this, set `combination_mode` to `poll` and provide a `poll_options` object. Here is an example:
{
"trigger_on": "schedule",
"submission_period": 12,
"combination_mode": "poll",
"poll_options": {
"title": "Take a poll about some jokes",
"instructions": "Please rank these jokes from most funny (5) to least funny (1)",
"assignments": 3,
"row_template": "<$.joke>"
},
"hit": {
"assignments": 5,
"title": "Tell a joke",
"description": "Please tell me a joke",
"reward": 0.05,
"lifetime_in_seconds": "3600",
"questions": [
{
"type": "free_text",
"key": "joke",
"name": "Your joke",
"required": "true",
"question": "Joke",
"min_length": "2",
"max_length": "2000"
}
]
}
}
Resulting events will have the original `answers`, as well as the `poll` results, and a field called `best_answer` that contains the best answer as determined by the poll.
# Other settings
`lifetime_in_seconds` is the number of seconds a HIT is left on Amazon before it's automatically closed. The default is 1 day.
As with most Agents, `expected_receive_period_in_days` is required if `trigger_on` is set to `event`.
MD
event_description <<-MD
Events look like:
{
"answers": [
{
"feedback": "Hello!",
"sentiment": "happy"
}
]
}
MD
def validate_options
options['hit'] ||= {}
options['hit']['questions'] ||= []
errors.add(:base, "'trigger_on' must be one of 'schedule' or 'event'") unless %w[schedule event].include?(options['trigger_on'])
errors.add(:base, "'hit.assignments' should specify the number of HIT assignments to create") unless options['hit']['assignments'].present? && options['hit']['assignments'].to_i > 0
errors.add(:base, "'hit.title' must be provided") unless options['hit']['title'].present?
errors.add(:base, "'hit.description' must be provided") unless options['hit']['description'].present?
errors.add(:base, "'hit.questions' must be provided") unless options['hit']['questions'].present? && options['hit']['questions'].length > 0
if options['trigger_on'] == "event"
errors.add(:base, "'expected_receive_period_in_days' is required when 'trigger_on' is set to 'event'") unless options['expected_receive_period_in_days'].present?
elsif options['trigger_on'] == "schedule"
errors.add(:base, "'submission_period' must be set to a positive number of hours when 'trigger_on' is set to 'schedule'") unless options['submission_period'].present? && options['submission_period'].to_i > 0
end
if options['hit']['questions'].any? { |question| %w[key name required type question].any? {|k| !question[k].present? } }
errors.add(:base, "all questions must set 'key', 'name', 'required', 'type', and 'question'")
end
if options['hit']['questions'].any? { |question| question['type'] == "selection" && (!question['selections'].present? || question['selections'].length == 0 || !question['selections'].all? {|s| s['key'].present? } || !question['selections'].all? { |s| s['text'].present? })}
errors.add(:base, "all questions of type 'selection' must have a selections array with selections that set 'key' and 'name'")
end
if take_majority? && options['hit']['questions'].any? { |question| question['type'] != "selection" }
errors.add(:base, "all questions must be of type 'selection' to use the 'take_majority' option")
end
if create_poll?
errors.add(:base, "poll_options is required when combination_mode is set to 'poll' and must have the keys 'title', 'instructions', 'row_template', and 'assignments'") unless options['poll_options'].is_a?(Hash) && options['poll_options']['title'].present? && options['poll_options']['instructions'].present? && options['poll_options']['row_template'].present? && options['poll_options']['assignments'].to_i > 0
end
end
def default_options
{
'expected_receive_period_in_days' => 2,
'trigger_on' => "event",
'hit' =>
{
'assignments' => 1,
'title' => "Sentiment evaluation",
'description' => "Please rate the sentiment of this message: '<$.message>'",
'reward' => 0.05,
'lifetime_in_seconds' => 24 * 60 * 60,
'questions' =>
[
{
'type' => "selection",
'key' => "sentiment",
'name' => "Sentiment",
'required' => "true",
'question' => "Please select the best sentiment value:",
'selections' =>
[
{ 'key' => "happy", 'text' => "Happy" },
{ 'key' => "sad", 'text' => "Sad" },
{ 'key' => "neutral", 'text' => "Neutral" }
]
},
{
'type' => "free_text",
'key' => "feedback",
'name' => "Have any feedback for us?",
'required' => "false",
'question' => "Feedback",
'default' => "Type here...",
'min_length' => "2",
'max_length' => "2000"
}
]
}
}
end
def working?
last_receive_at && last_receive_at > options['expected_receive_period_in_days'].to_i.days.ago && !recent_error_logs?
end
def check
review_hits
if options['trigger_on'] == "schedule" && (memory['last_schedule'] || 0) <= Time.now.to_i - options['submission_period'].to_i * 60 * 60
memory['last_schedule'] = Time.now.to_i
create_basic_hit
end
end
def receive(incoming_events)
if options['trigger_on'] == "event"
incoming_events.each do |event|
create_basic_hit event
end
end
end
protected
def take_majority?
options['combination_mode'] == "take_majority" || options['take_majority'] == "true"
end
def create_poll?
options['combination_mode'] == "poll"
end
def event_for_hit(hit_id)
if memory['hits'][hit_id].is_a?(Hash)
Event.find_by_id(memory['hits'][hit_id]['event_id'])
else
nil
end
end
def hit_type(hit_id)
if memory['hits'][hit_id].is_a?(Hash) && memory['hits'][hit_id]['type']
memory['hits'][hit_id]['type']
else
'user'
end
end
def review_hits
reviewable_hit_ids = RTurk::GetReviewableHITs.create.hit_ids
my_reviewed_hit_ids = reviewable_hit_ids & (memory['hits'] || {}).keys
if reviewable_hit_ids.length > 0
log "MTurk reports #{reviewable_hit_ids.length} HITs, of which I own [#{my_reviewed_hit_ids.to_sentence}]"
end
my_reviewed_hit_ids.each do |hit_id|
hit = RTurk::Hit.new(hit_id)
assignments = hit.assignments
log "Looking at HIT #{hit_id}. I found #{assignments.length} assignments#{" with the statuses: #{assignments.map(&:status).to_sentence}" if assignments.length > 0}"
if assignments.length == hit.max_assignments && assignments.all? { |assignment| assignment.status == "Submitted" }
inbound_event = event_for_hit(hit_id)
if hit_type(hit_id) == 'poll'
# handle completed polls
log "Handling a poll: #{hit_id}"
scores = {}
assignments.each do |assignment|
assignment.answers.each do |index, rating|
scores[index] ||= 0
scores[index] += rating.to_i
end
end
top_answer = scores.to_a.sort {|b, a| a.last <=> b.last }.first.first
payload = {
'answers' => memory['hits'][hit_id]['answers'],
'poll' => assignments.map(&:answers),
'best_answer' => memory['hits'][hit_id]['answers'][top_answer.to_i - 1]
}
event = create_event :payload => payload
log "Event emitted with answer(s) for poll", :outbound_event => event, :inbound_event => inbound_event
else
# handle normal completed HITs
payload = { 'answers' => assignments.map(&:answers) }
if take_majority?
counts = {}
options['hit']['questions'].each do |question|
question_counts = question['selections'].inject({}) { |memo, selection| memo[selection['key']] = 0; memo }
assignments.each do |assignment|
answers = ActiveSupport::HashWithIndifferentAccess.new(assignment.answers)
answer = answers[question['key']]
question_counts[answer] += 1
end
counts[question['key']] = question_counts
end
payload['counts'] = counts
majority_answer = counts.inject({}) do |memo, (key, question_counts)|
memo[key] = question_counts.to_a.sort {|a, b| a.last <=> b.last }.last.first
memo
end
payload['majority_answer'] = majority_answer
if all_questions_are_numeric?
average_answer = counts.inject({}) do |memo, (key, question_counts)|
sum = divisor = 0
question_counts.to_a.each do |num, count|
sum += num.to_s.to_f * count
divisor += count
end
memo[key] = sum / divisor.to_f
memo
end
payload['average_answer'] = average_answer
end
end
if create_poll?
questions = []
selections = 5.times.map { |i| { 'key' => i+1, 'text' => i+1 } }.reverse
assignments.length.times do |index|
questions << {
'type' => "selection",
'name' => "Item #{index + 1}",
'key' => index,
'required' => "true",
'question' => Utils.interpolate_jsonpaths(options['poll_options']['row_template'], assignments[index].answers),
'selections' => selections
}
end
poll_hit = create_hit 'title' => options['poll_options']['title'],
'description' => options['poll_options']['instructions'],
'questions' => questions,
'assignments' => options['poll_options']['assignments'],
'lifetime_in_seconds' => options['poll_options']['lifetime_in_seconds'],
'reward' => options['poll_options']['reward'],
'payload' => inbound_event && inbound_event.payload,
'metadata' => { 'type' => 'poll',
'original_hit' => hit_id,
'answers' => assignments.map(&:answers),
'event_id' => inbound_event && inbound_event.id }
log "Poll HIT created with ID #{poll_hit.id} and URL #{poll_hit.url}. Original HIT: #{hit_id}", :inbound_event => inbound_event
else
event = create_event :payload => payload
log "Event emitted with answer(s)", :outbound_event => event, :inbound_event => inbound_event
end
end
assignments.each(&:approve!)
hit.dispose!
memory['hits'].delete(hit_id)
end
end
end
def all_questions_are_numeric?
options['hit']['questions'].all? do |question|
question['selections'].all? do |selection|
selection['key'] == selection['key'].to_f.to_s || selection['key'] == selection['key'].to_i.to_s
end
end
end
def create_basic_hit(event = nil)
hit = create_hit 'title' => options['hit']['title'],
'description' => options['hit']['description'],
'questions' => options['hit']['questions'],
'assignments' => options['hit']['assignments'],
'lifetime_in_seconds' => options['hit']['lifetime_in_seconds'],
'reward' => options['hit']['reward'],
'payload' => event && event.payload,
'metadata' => { 'event_id' => event && event.id }
log "HIT created with ID #{hit.id} and URL #{hit.url}", :inbound_event => event
end
def create_hit(opts = {})
payload = opts['payload'] || {}
title = Utils.interpolate_jsonpaths(opts['title'], payload).strip
description = Utils.interpolate_jsonpaths(opts['description'], payload).strip
questions = Utils.recursively_interpolate_jsonpaths(opts['questions'], payload)
hit = RTurk::Hit.create(:title => title) do |hit|
hit.max_assignments = (opts['assignments'] || 1).to_i
hit.description = description
hit.lifetime = (opts['lifetime_in_seconds'] || 24 * 60 * 60).to_i
hit.question_form AgentQuestionForm.new(:title => title, :description => description, :questions => questions)
hit.reward = (opts['reward'] || 0.05).to_f
#hit.qualifications.add :approval_rate, { :gt => 80 }
end
memory['hits'] ||= {}
memory['hits'][hit.id] = opts['metadata'] || {}
hit
end
# RTurk Question Form
class AgentQuestionForm < RTurk::QuestionForm
needs :title, :description, :questions
def question_form_content
Overview do
Title do
text @title
end
Text do
text @description
end
end
@questions.each.with_index do |question, index|
Question do
QuestionIdentifier do
text question['key'] || "question_#{index}"
end
DisplayName do
text question['name'] || "Question ##{index}"
end
IsRequired do
text question['required'] || 'true'
end
QuestionContent do
Text do
text question['question']
end
end
AnswerSpecification do
if question['type'] == "selection"
SelectionAnswer do
StyleSuggestion do
text 'radiobutton'
end
Selections do
question['selections'].each do |selection|
Selection do
SelectionIdentifier do
text selection['key']
end
Text do
text selection['text']
end
end
end
end
end
else
FreeTextAnswer do
if question['min_length'].present? || question['max_length'].present?
Constraints do
lengths = {}
lengths['minLength'] = question['min_length'].to_s if question['min_length'].present?
lengths['maxLength'] = question['max_length'].to_s if question['max_length'].present?
Length lengths
end
end
if question['default'].present?
DefaultText do
text question['default']
end
end
end
end
end
end
end
end
end
end
end
|
