Can we use your REST APIs to convert Word to PDF in SharePoint Online via a workflow?
Thanks for your inquiry. We are checking this scenario and will get back to you soon,
As for accessing Cloud in SharePoint Online via a workflow, we unfortunately didn't come across this scenario before and we need some more time to do full investigations. But what we can understand, there are some options.
1. Client's documents are stored inside some third party cloud hosting and he wants to convert them from SharePoint Online workflow using appropriate API (REST).
2. Client's documents are stored inside his SharePoint Online site and he wants to convert them without installing anything. So it will be necessary to
a) upload a doc to cloud hosting,
b) convert them using API and
c) download converted doc back to SharePoint site
From the first glance we can not see any obstacles to use both of them, but we need to ensure that it is possible to initiate API calls from SharePoint workflow logic (and how to do this).
As a possible third option, we would need to check whether one can install third party applications right into his SharePoint Online site. If it is possible then we can just install Aspose.Words for SharePoint (and license) inside SharePoint Online and convert docs without any API calls to external cloud services.