Sample global and custom policies for DataPower APIGateway (part of IBM API Connect) API Gateway is available in API Connect V10
A global policy runs before or after certain APIs and is it's own assembly. A user defined policy is a "building block" in the assembly that does something in the API. have a look at this very basic policy
To deploy them there are multiple ways to achieve this, in short it's gateway configuration that needs to somehow get to the gateway the possible mechanisms are
- a gateway extension
- direct on the gateway (using a config sequence possibly )
- using the custom resource and drive through the operator.
To create and handle global policies have a read through of this page. https://www.ibm.com/docs/en/api-connect/10.0.5.x_lts?topic=policies-authoring-datapower-api-gateway
For user defined policies, these are just DataPower configuration the APIgw will push their availability to API manager