Container Orchestrator from scratch
- Language:
Go - Containerization:
Docker Go SDK - Networking:
chi - Data Storage:
BoltDB - Metrics:
goprocinfo - CLI:
Cobra
- Task: the smallest unit of work, specifies a container image to run, resource requirements and a restart policy.
- Scheduler: responsible for placing tasks on nodes based on resource availability and task requirements, computes a score for each node.
- Manager: accepts tasks submissions, collects metrics from workers, keeps track of tasks, their states, and the machine on which they run.
- Worker: executes tasks assigned by the manager, reports status and metrics back to the manager.
- CLI: command-line interface for users to interact with the orchestrator, submit tasks, and check status.
| Feature | Status |
|---|---|
| Starting, stopping, deleting docker containers | ✔️ |
| Starting, stopping, deleting tasks | ✔️ |
| Checking validity of state transitions | ✔️ |
| Collecting and exposing tasks' metrics | ✔️ |
| Worker API (task submission, task list, task deletion) | ✔️ |
| Manager control loop | ✔️ |
| Scheduling tasks on workers (RoundRobin, E-PVM) | ✔️ |
| Task Health Checks and Restart Policies | ✔️ |
| Manager API (task submission, task list, task deletion) | ✔️ |
| Persistent storage (BoltDB) | ✔️ |
| CLI | ✔️ |
| Service Discovery | ❌ |
| High availability | ❌ |
| Load balancer | ❌ |
| Security | ❌ |
Start the manager
go run main.go manager
Start a worker
go run main.go worker
Run a new task:
go run main.go task --filename data/task1.json
Check tasks status:
go run main.go status
Stop a task:
go run main.go stop <task_id>
Get node information:
go run main.go node
Manager API:
+---------+-------------------+--------------------------------------------+
| Method | Route | Description |
+---------+-------------------+--------------------------------------------+
| GET | /tasks | Gets a list of all tasks |
| POST | /tasks | Creates a task |
| DELETE | /tasks/{taskID} | Stops the task identified by taskID |
| GET | /nodes | Gets a list of nodes |
+---------+-------------------+--------------------------------------------+
Worker API:
+--------+-------------------+--------------------------------------------+
| Method | Route | Description |
+--------+-------------------+--------------------------------------------+
| GET | /tasks | Gets a list of all tasks |
| POST | /tasks | Creates a task |
| DELETE | /tasks/{taskID} | Stops the task identified by taskID |
| GET | /stats | Gets metrics about the worker |
+--------+-------------------+--------------------------------------------+