PDFreactor can be deployed as a Java web application to Azure using an appropriate application server like Jetty. You can download the PDFreactor Web Service web application archive here: https://www.pdfreactor.com/download/get/?product=pdfreactor&type=webservice&jre=false
The download is a ZIP file which also contains a Readme with instructions on how to deploy PDFreactor on Azure. To use the PDFreactor Web Service, you might also need the PDFreactor client APIs available here: https://www.pdfreactor.com/download/get/?product=pdfreactor&type=webservice_clients&jre=false
For more information about the PDFreactor Web Service, please refer to the PDFreactor manual here: https://www.pdfreactor.com/product/doc_html/index.html#UsingTheWebservice