Converting data

Representing a Feed

The cosm-rb library makes it easy to convert Ruby objects into Cosm ones.

feed = Cosm::Feed.new # initialize a new Feed object
feed.title = "My Cosm Feed"
feed.datastreams = [Cosm::Datastream.new(:id => 'test')] # Let's give it one datastream with id 'test'

Let's see what it looks like:

feed.to_json
=> {"title":"Test feed","version":"1.0.0","datastreams":[{"id":"test"}]}

You can also represent objects in Cosm xml and csv

Parsing a feed

The cosm-rb library makes it easy to convert Cosm data into a Ruby object

Parsing a Datastream using json

    json = ' 
      {   
          "max_value": "658.0",
          "current_value": "14",
          "datapoints": [{
              "value": "1",
              "at": "2011-03-02T15:59:56.895922Z"
          },  
          {   
              "value": "1",
              "at": "2011-03-02T16:00:07.188648Z"
          },  
          {   
              "value": "2",
              "at": "2011-03-02T16:00:18.416500Z"
          }], 
          "min_value": "0.0",
          "id": "0",
          "tags": ["humidity", "Temperature", "freakin lasers"],
          "version": "1.0.0",
          "unit": {
              "label": "percentage",
              "symbol": "%",
              "type": "derived SI" 
          },  
          "at": "2011-02-16T16:21:01.834174Z"
      }'  
    datastream = Cosm::Datastream.new(json)
    datastream.to_xml # =>
    # <?xml version="1.0" encoding="UTF-8"?>
    # <eeml xmlns="http://www.eeml.org/xsd/0.5.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="0.5.1" xsi:schemaLocation="http://www.eeml.org/xsd/0.5.1 http://www.eeml.org/xsd/0.5.1/0.5.1.xsd">
    #   <environment creator="" updated="2011-02-16T16:21:01.834174Z" id="">
    #     <data id="0">
    #       <tag>freakin lasers</tag>
    #       <tag>humidity</tag>
    #       <tag>Temperature</tag>
    #       <current_value at="2011-02-16T16:21:01.834174Z">14</current_value>
    #       <max_value>658.0</max_value>
    #       <min_value>0.0</min_value>
    #       <unit type="derived SI" symbol="%">percentage</unit>
    #       <datapoints>
    #         <value at="2011-03-02T15:59:56.895922Z">1</value>
    #         <value at="2011-03-02T16:00:07.188648Z">1</value>
    #         <value at="2011-03-02T16:00:18.416500Z">2</value>
    #       </datapoints>
    #     </data>
    #   </environment>
    # </eeml>