Deployment Architecture

graph TB
    subgraph cluster["Kubernetes Cluster"]

        subgraph controlplane["Kubernetes Control Plane"]
            APIServer["Kubernetes API Server"]
        end

        subgraph node1["Kubernetes Node 1"]
            K1[Kubelet]
            subgraph ds1["CSI Driver Pod (DaemonSet)"]
                N1[CSI Driver Node Service]
                R1[CSI Driver Registrar Sidecar]
                L1[CSI Driver Liveness Probe]
            end
            subgraph init1["CSI Driver Init Container"]
                I1[mount-s3 Installer: Copies binary to host]
            end
            S1[Host systemd]
            M1[mount-s3 FUSE processes: One per mounted volume]
            A1[Application Pods]
        end

        subgraph node2["Kubernetes Node 2"]
            subgraph controller["CSI Controller Deployment"]
                subgraph controllerPod["Controller Pod (1 replica)"]
                    CSIController["CSI Controller Service"]
                    CSIProvisioner["CSI Provisioner Sidecar(Watch PVC)"]
                end
            end
            K2[Kubelet]
            subgraph ds2["CSI Driver Pod (DaemonSet)"]
                N2[CSI Driver Node Service]
                R2[CSI Driver Registrar Sidecar]
                L2[CSI Driver Liveness Probe]
            end
            subgraph init2["CSI Driver Init Container"]
                I2[mount-s3 Installer: Copies binary to host]
            end
            S2[Host systemd]
            M2[mount-s3 FUSE processes: One per mounted volume]
            A2[Application Pods]
        end

        subgraph node3["Kubernetes Node N..."]
            K3[Kubelet]
            subgraph ds3["CSI Driver Pod (DaemonSet)"]
                N3[CSI Driver Node Service]
                R3[CSI Driver Registrar Sidecar]
                L3[CSI Driver Liveness Probe]
            end
            subgraph init3["CSI Driver Init Container"]
                I3[mount-s3 Installer: Copies binary to host]
            end
            S3[Host systemd]
            M3[mount-s3 FUSE processes: One per mounted volume]
            A3[Application Pods]
        end


    end

    S3Storage[S3 Storage Endpoint]

    %% Controller operations (Dynamic Provisioning)
    APIServer <-->|"Watch PVC/StorageClass, Resolve PV/PVC Templates, Create PV, Update PVC Status"| CSIProvisioner
    CSIProvisioner -->|"CreateVolume/DeleteVolume RPC | Unix socket /csi/csi.sock"| CSIController
    CSIController -->|"Bucket Create/Delete via S3 API"| S3Storage

    %% Init container flow
    I1 -.->|Install binary to /opt/mountpoint-s3-csi/bin/| S1
    I2 -.->|Install binary to /opt/mountpoint-s3-csi/bin/| S2
    I3 -.->|Install binary to /opt/mountpoint-s3-csi/bin/| S3

    %% CSI Driver Registration
    R1 -->|Register via /registration/ entry| K1
    R2 -->|Register via /registration/ entry| K2
    R3 -->|Register via /registration/ entry| K3

    %% Health monitoring
    L1 -->|Monitor Unix socket /csi/csi.sock| N1
    L2 -->|Monitor Unix socket /csi/csi.sock| N2
    L3 -->|Monitor Unix socket /csi/csi.sock| N3

    %% Node operations
    K1 -->|Volume requests via gRPC on host Unix socket| N1
    K2 -->|Volume requests via gRPC on host Unix socket| N2
    K3 -->|Volume requests via gRPC on host Unix socket| N3

    N1 -->|Create/stop services via D-Bus| S1
    N2 -->|Create/stop services via D-Bus| S2
    N3 -->|Create/stop services via D-Bus| S3

    S1 -->|Start/stop/monitor processes| M1
    S2 -->|Start/stop/monitor processes| M2
    S3 -->|Start/stop/monitor processes| M3

    %% Application access
    A1 -->|File I/O| M1
    A2 -->|File I/O| M2
    A3 -->|File I/O| M3

    %% S3 connections
    M1 -->|S3 API| S3Storage
    M2 -->|S3 API| S3Storage
    M3 -->|S3 API| S3Storage

    %% Styling for clarity without colors
    classDef optional stroke-dasharray: 5 5