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Deployment starts with sending of a custom discovery event, that notifies all nodes in the cluster about the ongoing deployment. This message contains serialized service instance and its configuration. It is delivered to the coordinator node first, that calculates the service deployment assignments and adds this information to the message. During the following round-trip of this message, nodes save information about service deployment assignments to some local storage, and the ones, that were chosen to deploy the services, do it perform initialisation asynchronously in a dedicated thread pool.

Once the a node finishes the deployment procedure and Service#init() method execution, it connects to the coordinator, using the communication SPI, and sends the deployment result to it, i.e. either acknowledgement about successful deployment, or a serialized exception.

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It should be possible to update service implementation without downtime. Employment of Deployment SPI should solve this problem.

Service processor should subscribe to class deployments and restart corresponding services, when their classes change.

The basic usage scenario involves enabling UriDeploymentSpi and updating the JAR files, containing implementation classes. It will lead to existing services cancellation and reployment. It implies, that services should be ready to sudden cancellations. Documentation should contain explanation of this fact with examples. 

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