What would be the Best Practice to promote Appian webservice to higher environment?

One thing i would like to suggest if the same Service is used in the SAIL rule.You can write an Expression rule to derive the endpoints in each environment. Parametrise the environemnt url part using constants, and use them in the rule as they would differ for each environement, after deploying you can update the constant to hold the current Environrment value.

Mohamed, that would be right thing to do when Appian is consuming an external service. The case here is when Appian Process Model is exposed as webservice and Application package doesn't have any means to package such webservices. So far, looks like the webservices need to be created manually in higher environment.

I don't think there is any good way. We are also publishing the process model as a service, explicitly, after migration to Production. We need to be careful to keep the service name same so that the constants (storing the service context part of the service WSDL URL)can have same value in all environment. We can keep a separate environment specific constant to just contain the server domain name part of the WSDL URL.

Process models published as web service is not exportable Appian object, atleast not yet. So as other practitioners suggested manually create/document the steps for promoting.

I suggest you look in to WebAPI.

Can you expose a process model as SOAP service using WebAPI? I guess those are for REST APIs.

Can you expose a process model as SOAP service using WebAPI? I guess those are for REST APIs.