Applications and microservices
An application is a named group on the control plane. Microservices that belong together share that name. NATS account policy lives on the application, so every service in the group uses the same account rules.
A microservice is one container on one Edgelet node. In YAML that node is kind: Agent. The CLI name is application/microservice, for example line-monitor/reader.
---
apiVersion: datasance.com/v3
kind: Microservice
metadata:
name: line-monitor/reader
spec:
agent:
name: edge-1
spec.agent.name is the Edgelet node that runs this container. Deploy the application before this microservice, or put both documents in the same file and let potctl deploy -f create them together.
You can list the microservices inside the application document, or add a microservice later with its own document. Either way the application is the group, and the microservice is the container.
NATS account rules stay on the application. When a single service needs its own subject permissions, the NATS user rule goes on that microservice. The control plane provisions the credentials.
System applications
Datasance PoT creates a system application for each Edgelet node, named system-<agentName>. That application holds the platform containers for that node: router, NATS, and debug. Operators inspect those containers. They do not deploy them as user applications.
You can also browse user and system workloads in EdgeOps Console.
Day-2 actions
Logs, exec, move, and rename are the day-2 actions on a running microservice. Logs and exec inspect the container, move places it on another Edgelet node, and rename changes the application/microservice name. The procedures are in Microservices and Logs and exec.