horizonsForEach.rst

Repetition

This section continues implementing the requirements of :ref:`horizonsInterfaces`. The aim is to read an XML document with a booking and insert it in database tables "booking" and "visit". In section :ref:`insertDb` , we did the insert in table "booking". The inserted values were fetched using XPath expressions. In the previous section :ref:`transform`, we transformed the booking XML such that the values for each "visit" row are grouped together. In this section, we will insert these rows.

A booking can have multiple destinations, each appearing in their own <destination> element. These elements can be iterated with the <ForEachChildElementPipe>. Within this pipe you include a sender that is applied to each element, in our case a <destination> element. Please do the following to do the inserts in table "visit":

1. Please open Configuration.xml.
2. Add a <ForEachChildElementPipe> as shown:

The <ForEachChildElementPipe> applies the elementXPathExpression to the incoming message and iterates over the result set. In the transformed example booking shown in :ref:`transform`, there is one match:

<destination>
  <bookingId>1</bookingId>
  <seq>1</seq>
  <hostId>3</hostId>
  <productId>4</productId>
  <startDate>2018-12-27</startDate>
  <endDate>2019-01-02</endDate>
  <price>400.00</price>
</destination>

3. Replace the <!-- You will add your sender here --> line with the following XML:

This sender is similar to the sender of section :ref:`insertDb`. There is an INSERT query with a question mark for each inserted value. The inserted values are fetched using XPath expressions, which act on the current match of the elementXPathExpression as shown at step 2.