class Query

Query¶ ↑

The Query contains a run function which is called by its children (Nodes, Ways, Relations, etc.) with specific arguments which tells the database connection which collection to query.

The #run function will always return buckets as build by AnalysisWindow#build_buckets

Attributes

analysis_window[R]

buckets[R]

selector[RW]

Public Class Methods

new(args) click to toggle source

# File models/Query.rb, line 15
def initialize(args)
        @analysis_window = args[:analysis_window]

        @selector = {}

        post_initialize(args)
end

Public Instance Methods

post_initialize(args) click to toggle source

Updates the bounding box, time frame, and constraints for the query to Mongo.

The bounding_box geographic constriaints are currently unimplemented because the database doesn't contain any points outside of the bounding box.

# File models/Query.rb, line 27
def post_initialize(args)

        if analysis_window.bounding_box.active
                selector[:geometry] = { '$within' => analysis_window.bounding_box.mongo_format }
        end

        #This should be over-written farther down, but it's here for safety
        if analysis_window.time_frame.active
                selector[:created_at] = { '$gte' => analysis_window.time_frame.start_date,
                                                                  '$lt' => analysis_window.time_frame.end_date    }
        end

        #If the query was called with new constraints, then they should get added here
        unless args[:constraints].nil?
                selector.update(args[:constraints])
        end
end

run(args = {}) click to toggle source

The main run function which is called as super from children.

Accesses the database through the Singleton DatabaseConnection reference and queries with the selector that was built.

# File models/Query.rb, line 54
def run(args = {})
        # puts "Got to super run function with args #{args}"
        @buckets = analysis_window.build_buckets( unit = args[:unit], step = args[:step] )

        unless args[:constraints].nil?
                selector.update(args[:constraints])
        end

        buckets.each do |bucket|                      
                update_created_at( bucket[:start_date], bucket[:end_date] )
                results = DatabaseConnection.database[args[:collection]].find( selector )
                results.each do |obj|
                        bucket[:objects] << args[:type].new(obj.from_mongo)
                end
        end
        buckets
end