StatisticsCollector policy

Basic example

<StatisticsCollector name="publishPurchaseDetails">
  <Statistics>
    <Statistic name="productID" ref="product.id" type="string">999999</Statistic>
    <Statistic name="price" ref="product.price" type="string">0</Statistic>
  </Statistics>
</StatisticsCollector>

In this example, you collect statistical information about two custom variables: product.id and product.price. On every request, the Statistics Collector policy writes the value of these two variables to the analytics server.

This example also sets an optional default value for each variable, where the default value of product.id is 999999 and the default product.price is 0. If a variable is undefined and you do not specify a default value, then no data is recordeded for the variable. If you specify a default value, then the default value is recorded when the variable is undefined.

After gathering statistical data, you can use the Edge management UI or API to retrieve the statistics. When retrieving statistics, you reference the data collected for these variables as productID and price, respectively.

Accessing statistics

In this example, you use the Edge management API to view the statistical data for the collection called productID. This request builds a custom report for product IDs based on the sum of message counts submitted for each product ID for each day. Substitute your organization name for the variable {org_name}, and substitute the email and password for your account on Apigee Edge for email:password.

Set the timeRange parameter to include the time interval when your data was collected. Data older than six months from the current date is not accessible by default. If you want to access data older than six months, contact Apigee Edge Support.

$ curl https://api.enterprise.apigee.com/v1/o/{org_name}/environments/test/stats/productID?"select=sum(message_count)&timeRange=1/19/2015%2000:00~6/21/2015%2000:00&timeUnit=day"
-u email:password

In the response, the name field contains the product ID and value shows the number of requests for each day:

{
  "environments" : [ {
    "dimensions" : [ {
      "metrics" : [ {
        "name" : "sum(message_count)",
        "values" : [ {
          "timestamp" : 1353369600000,
          "value" : "4.0"
        } ]
      } ],
      "name" : "52"
    }, {
      "metrics" : [ {
        "name" : "sum(message_count)",
        "values" : [ {
          "timestamp" : 1353369600000,
          "value" : "19.0"
        } ]
      } ],
      "name" : "14"
    }, ...
  } ],
  "metaData" : {
    "samplingRate" : "100"
  }
}

Extracting data for collection

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ExtractVariables async="false" continueOnError="false" enabled="true" name="GetWeatherData">
    <VariablePrefix>weather</VariablePrefix>
    <XMLPayload>
       <Namespaces>
          <Namespace prefix="yweather">http://xml.weather.yahoo.com/ns/rss/1.0</Namespace>
       </Namespaces>
       <Variable name="location" type="string">
          <XPath>/rss/channel/yweather:location/@city</XPath>
       </Variable>
       <Variable name="condition" type="string">
          <XPath>/rss/channel/item/yweather:condition/@text</XPath>
       </Variable>
    </XMLPayload>
</ExtractVariables>

The Statistics Collector policy requires that the data collected be stored in variables. These variables can be predefined by Apigee, or custom variables that you define.

In this example, you use the Extract Variables policy to extract data from an XML payload that contains weather information. This policy:

• Extracts the name of the city and writes it to a variable named weather.location
• Extracts the current conditions and writes it to a variable named weather.condition

You can then use the Statistics Collector policy to gather information about the variables, as shown below:

<StatisticsCollector name="publishPurchaseDetails">
  <Statistics>
    <Statistic name="weatherLocation" ref="weather.location" type="string"></Statistic>
    <Statistic name="weatherCondition" ref="weather.condition" type="string"></Statistic>
  </Statistics>
</StatisticsCollector>

For a complete tutorial that shows how to extract data from an XML payload for the Statistics Collector policy, see Analyze API message content using custom analytics.