Monitoring Data From Online Sources and APIs

Observu allows you to check availability on webpages and APIs and test them for presence of certain text. However, web pages and APIs can provide a wealth of information that is also interesting to track. Maybe your forum lists the current number of users or your API replies with the amount of requests that you have left.

Observu allows you to use regular expressions to capture this information and assign them to a property to be tracked every minute of every day.

Extracting numeric data from a web page

Let’s start with a simple example of extracting a row from a table.

<table>
   <tr>
     <td>EUR - USD</td><td>1.31567</td>
   </tr>
</table>

If we now set /EUR\w-\wUSD<\/td>

Extracting data from an API

Maybe the same page also publishes this data as XML:

<currency>
  <from>EUR</from>
  <to>USD</to>
  <value>1.31567</value>
</currency>

If we now set /value>([0-9\.]+)/si as expression in our advanced capturing settings and then assign it to: currency.EUR_to_USD:float Observu can again keep track of the rates published through this API.

Read more about monitoring your API

The :float at the end of the property name is type hinting to make sure Observu knows how to render and report on the extracted data. Our documentation lists all available types