The HTTP client step doesn't do anything
Q: The HTTP client step doesn't do anything, how do I make it work?
A: The HTTP client step needs to be triggered. Use a Row generator step generating e.g. 1 empty row and link that with a hop to the HTTP client step.
The HTTP client step and SOAP
Q: Does the HTTP client support SOAP?
A: No, it just calls an URL with arguments. Future steps may provide SOAP functionality, Work is underway on a WebService step supporting WSDL. The first experimental version appeared in PDI v2.5.0