Component Orchestrator

Introduction

The Component Orchestrator is responsible for fair resource distribution.

Implementation Service File

Technologies used

• Node.js
• Kubernetes
• Docker

How it works

In a multi-tenant environment, it must be guaranteed that a user or tenant (intentionally or unintentionally) may not get an unfair usage of shared resources such as CPU, Memory, Network, etc. It must be guaranteed that every integration flow gets a chance to be executed, close to the intervals defined by its Cron expression.

The Component Orchestrator is a service defining the fairness policy and controlling that each user/flow/tenant is complying with that policy. The Component Orchestrator is responsible for:

• Protection from over-scheduling: if the execution of flow takes longer than its scheduling interval, the following executions must be skipped.
• Making sure that flow or its steps are not deployed multiple times
• If scaling is configured for a flow, the specified number of instances must be deployed
• Detection of policy violations and punishment of “bad citizens”

Interaction with other Services

• Interacts with IAM to introspect provided IAM token.
• Gets events for starting a flow from the Flow Repository.
• Gets events for starting a global component.
• Deploys containers to the Kubernetes cluster.
• Sends events into the event bus when the deployment is complete.
• Creates IAM tokens in IAM service.
• Gets Component information from the Component Repository.
• Executes each step in a flow by publishing to message queues

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