Class: QME::MapReduce::Builder

Inherits:
Object
  • Object
show all
Defined in:
lib/qme/map/map_reduce_builder.rb

Overview

Builds Map and Reduce functions for a particular measure

Defined Under Namespace

Classes: Context

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(db, measure_def, params) ⇒ Builder

Create a new Builder

Parameters:

  • measure_def (Hash) —

    a JSON hash of the measure, field values may contain Erb directives to inject the values of supplied parameters into the map function

  • params (Hash) —

    a hash of parameter names (String or Symbol) and their values



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# File 'lib/qme/map/map_reduce_builder.rb', line 47

def initialize(db, measure_def, params)
  @id = measure_def['id']
  @params = {}
  @db = db
  
  # normalize parameters hash to accept either symbol or string keys
  params.each do |name, value|
    @params[name.to_s] = value
  end
  @measure_def = measure_def
  @measure_def['parameters'] ||= {}
  @measure_def['parameters'].each do |parameter, value|
    if !@params.has_key?(parameter)
      raise "No value supplied for measure parameter: #{parameter}"
    end
  end
  # if the map function is specified then replace any erb templates with their values
  # taken from the supplied params
  # always true for actual measures, not always true for unit tests
  if (@measure_def['map_fn'])
    template = ERB.new(@measure_def['map_fn'])
    context = Context.new(@db, @params)
    @measure_def['map_fn'] = template.result(context.get_binding)
  end
end

Instance Attribute Details

#id ⇒ Object (readonly)

Returns the value of attribute id.



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# File 'lib/qme/map/map_reduce_builder.rb', line 9

def id
  @id
end

#params ⇒ Object (readonly)

Returns the value of attribute params.



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# File 'lib/qme/map/map_reduce_builder.rb', line 9

def params
  @params
end

Instance Method Details

#finalize_function ⇒ String

Get the reduce function for the measure, this is a simple wrapper for the reduce utility function specified in map-reduce-utils.js

Returns:

  • (String) —

    the reduce function



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# File 'lib/qme/map/map_reduce_builder.rb', line 83

def finalize_function
  reduce = 
  "function (key, value) { 
    var patient = value;
    patient.measure_id = \"#{@measure_def['id']}\";\n"
  if @params['test_id'] && @params['test_id'].class==BSON::ObjectId
    reduce += "  patient.test_id = new ObjectId(\"#{@params['test_id']}\");\n"
  end
  if @measure_def['sub_id']
    reduce += "  patient.sub_id = \"#{@measure_def['sub_id']}\";\n"
  end
    
  reduce += "patient.effective_date = #{@params['effective_date']};
             if (patient.provider_performances) {
               var tmp = [];
               for(var i=0; i<patient.provider_performances.length; i++) {
                 var value = patient.provider_performances[i];
                 if ((value['start_date'] <= #{@params['effective_date']} || value['start_date'] == null) && (value['end_date'] >= #{@params['effective_date']} || value['end_date'] == null))
                 tmp.push(value);
               }
               if (tmp.length == 0) tmp = null;
               patient.provider_performances = tmp;
             }
             return patient;}"
  
  reduce
end

#map_function ⇒ String

Get the map function for the measure

Returns:

  • (String) —

    the map function



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# File 'lib/qme/map/map_reduce_builder.rb', line 75

def map_function
  @measure_def['map_fn']
end