Create user-defined policies to
control extra processing features in the Gateway server, such as security, or
routing of requests. The user-defined policies
feature is available only with the on-premise offering of IBM® API
Connect.
When would you need a user-defined policy?
Create a user-defined policy in IBM API
Connect when you need to augment the actions or activities that are performed by the API gateway. For example, you might want to perform the following operations:
Implement your own proprietary logic for dynamic routing of requests.
Enforce extra security constraints to your API.
Make accessible an extra capability that is provided in DataPower® that is not yet accessible in the IBM API
Connect policy catalog.
How do user-defined policies work?
A user-defined policy is
implemented in one of the following ways depending on the platform:
For an IBM
DataPower Gateway, as a DataPower processing
rule.
For a Micro Gateway, as a Node.js module.
Note:User-defined policies
for the Micro Gateway are
marked as to indicate that the implementation might change in a future release.
IBM API
ConnectMicro Gateway is deprecated in IBM API
Connect Version 5.0.8 in favor of DataPower Gateway. From 1 April 2020, Micro Gateway, and associated toolkit CLI commands, will no longer
be supported. Existing users can migrate their API definitions to IBM
DataPower Gateways. For information on supported API policies, see
Built-in
policies.
After a policy is imported into an IBM API
Connect Catalog, the policy is
available to be placed into an assembly flow of an enforced API. When the API is published, and
invoked by an application, the API Gateway executes all
policies that are associated with this API depending on the platform:
An API Gateway
that is running in DataPower
calls the IBM
DataPower Gateway
processing rules that those policies implement.
A Micro Gateway runs the Node.js module that implements
the policy.
The following diagram provides an overview of how to create and execute a user-defined policy in IBM API
Connect.Figure 1. The user-defined policy process