We have a requirement where we have to communicate to another system using webse

Ideally, this should be architected with a middleware component if possible. Do you have a middleware team at your organization? If so, then you should have the middleware team provide a proxy service that Appian can call with UsernameToken (i.e. username and password).

1. Middleware provide a service that does the digital signature to the downstream service.
2. Appian calls the middleware service rather than the downstream service (using UsernameToken).


The above is the best approach.

If a middleware component is not an option, then you can write a plugin. To do the digital signature, you'll have to use something like:

1. axis2 and rampart
2. axis 1.3 and wss4j
3. jax-ws


I would use one of the older versions of Axis if I had to do this. The later versions have too many dependencies that often conflict with the classses/packages/jars that are made available via OSGI. With axis2 for example, you'll likely run into NoClassDefFoundError errors and that will take a while to resolve.