Architecture of Nublado controller#

The Nublado controller is a FastAPI application with three basic functions:

  1. Prepull images to every Kubernetes node.

  2. Manage user lab pods and their supporting environment.

  3. Manage user file server pods and their supporting environment.

Internally, the code structure uses the handler-services-storage code structure documented in SQR-072. To try to keep the size of the major services, such as the user lab manager, manageable, there are several layers of services that coordinate.

This diagram attempts to provide a guide to the overall code structure. The Kubernetes storage layer is further subdivided into per-resource storage layers, which are not shown in this graph to try to keep the graph more concise.

flowchart LR subgraph services prepuller(Prepuller) image(ImageService) lab(LabManager) fileserver(FileserverManager) image --> docker-source(DockerImageSource) image --> gar-source(GARImageSource) prepuller --> prepull-builder(PrepullerBuilder) prepuller --> image lab --> image lab --> lab-builder(LabBuilder) fileserver --> fileserver-builder(FileserverBuilder) lab-builder --> volume-builder(VolumeBuilder) fileserver-builder --> volume-builder end subgraph storage docker(DockerStorageClient) gar(GARStorageClient) metadata(MetadataStorage) fileserver-storage(FilserverStorage) fileserver-storage --> kubernetes(Kubernetes) lab-storage(LabStorage) lab-storage --> kubernetes node-storage(NodeStorage) end docker-source --> docker gar-source --> gar fileserver --> fileserver-storage lab --> metadata lab --> lab-storage prepuller --> metadata prepuller --> kubernetes image --> node-storage main(app) --> handlers handlers --> image handlers --> prepuller handlers --> lab handlers --> fileserver background(BackgroundTaskManager) background --> image background --> prepuller background --> lab background --> fileserver

Internal structure#