API Gateway Deployment Model

The deployment process is carried out by a sequence of interactions that occur between CentraSite and API Gateway:

1. CentraSite pushes the virtual service that is ready for deployment to API Gateway.

2. API Gateway deploys the virtual service that was received from CentraSite along with its effective runtime policy.

The deployment process is initiated from CentraSite and is carried out by the Deployer service on API Gateway.

The diagram demonstrates the deployment process of virtual services to API Gateway.

Step	Description
1	An administrator initiates the deployment by selecting the assets that are to be deployed and specifies to which API Gateway they are to be deployed.
2	The Deployment Manager on CentraSite prepares the asset for deployment (the specific preparation steps depend on the type of asset being deployed) and invokes the deployer service on the API Gateway. The prepared asset is submitted as input to this service.
3	The deployer service deploys the asset in API Gateway.
4	If the deployment is successful, the deployer service returns a success message and data that is pertinent to the deployed asset. If the deployment is unsuccessful, the deployer service returns a failure message.
5	The Deployment Manager on CentraSite logs information about the deployment in the Deployment log. If the deployer service returned specific data about the asset, the asset's metadata is updated as needed in CentraSite.

Note:
When a virtual service is published to API Gateway, you cannot modify the runtime policy configuration for the virtual service in CentraSite. You can modify the runtime policy configuration through API Gateway only. However, to modify the runtime policy configuration of a virtual service through CentraSite, you must unpublish the virtual service from API Gateway.

General Guidelines for Effective Deployment of Virtual Services

CentraSite automatically validates the service's run-time policy (or policies) to ensure that:

Any action (for example, Log Invocation) that appears in a policy multiple times is allowed to appear multiple times.

All action dependencies in a policy are properly met.

CentraSite informs you of any violation and you have to correct the violations before deploying the service.

You must make modifications to deployed assets in CentraSite.

If you have to modify a virtual service that is already deployed, you must modify it in CentraSite and then redeploy it to API Gateway to synchronize the changes.

You cannot make changes to a runtime policy while it is active.

To make changes to a policy after it has been switched to the active state, you must do one of the following:

Switch the policy to the Suspended state (to deactivate it), update the policy, and then switch it back to the Productive state (to reactivate it).

Create a new version of the policy, make your changes to the new version of the policy, and then switch the new version to the Productive state. Switching the new version of the policy to the Productive state will automatically Retire (and deactivate) the old version.

If you have to update a runtime policy that is already deployed with virtual services that are in production, always use the second method described above (that is, create a new version of the policy). If you use the first method, which requires you to suspend the existing policy, the production services will be running without the policy while you are making revisions to it.

Conditions that Must be Satisfied for Effective Deployment of Virtual Services

To deploy a virtual service to a API Gateway, the following conditions must be met:

Ensure that you have the API Gateway Publisher role. Only users with this permission can deploy a virtual service. CentraSite will not enable the Publish icon for any other users.

Ensure that the API Gateway asset to which the virtual service will be deployed has already been created.

Ensure that the API Gateway's specified deployment URL is active and the user credentials of Integration Server are valid. To check this, go to the API Gateway's detail page and click the Publish button. If the connection is not active and valid, activate the deployment endpoint and modify the user credentials as required.

If the virtual service is under the control of an active lifecycle model (LCM), make sure that:

The virtual service is in a Deployable lifecycle state. If you are not certain of what the Deployable lifecycle state is, consult your CentraSite Administrator.

The virtual service has a design-time policy that includes the Change Deployment Status action and it is set to Yes. This action specifies whether the service is eligible for deployment.

If these conditions are not satisfied, all or part of the deployment user interface controls will be disabled when you view the virtual service.