Power Shelf State Diagram

This document describes the Finite State Machine (FSM) for Power Shelves in NICo: lifecycle from creation through initialization, ready, the OnDemand maintenance operations (PowerOn / PowerOff), and deletion. It also covers the operator-facing interfaces (CLI / gRPC) used to drive the OnDemand operations.

High-Level Overview

The main flow shows the primary states and transitions:

States

Transitions (by trigger)

OnDemand Maintenance Operations

The Maintenance state is entered on demand by an operator (or any other service) to drive a power-control operation on the shelf. Two operations are currently supported:

• PowerOn — powers the shelf on via the BMC / PMC.
• PowerOff — powers the shelf off via the BMC / PMC.

Operator interface (admin CLI)

The power-shelf maintenance subcommand (alias fix) drives one or more shelves into Maintenance. All listed shelves receive the same operation in a single atomic request — if any shelf is unknown or marked for deletion the entire request is rejected and no shelves are mutated.

$
# Single shelf
$
nico-admin-cli power-shelf maintenance power-off \
>
    --power-shelf-id <ID>
$
$
# Multiple shelves, repeated flag
$
nico-admin-cli power-shelf maintenance power-on \
>
    --power-shelf-id <ID1> \
>
    --power-shelf-id <ID2> \
>
    --reference https://tracker/MAINT-123
$
$
# Multiple shelves, single flag with several values
$
nico-admin-cli power-shelf maintenance power-off \
>
    --power-shelf-id <ID1> <ID2> <ID3>
$
$
# Using the visible aliases
$
nico-admin-cli power-shelf fix power-on --id <ID1> <ID2>

gRPC interface

The CLI is a thin wrapper over the NICo.SetPowerShelfMaintenance gRPC method:

1
rpc SetPowerShelfMaintenance(PowerShelfMaintenanceRequest) returns (google.protobuf.Empty);
2
3
enum PowerShelfMaintenanceOperation {
4
  POWER_SHELF_MAINTENANCE_OPERATION_UNSPECIFIED = 0;
5
  POWER_SHELF_MAINTENANCE_OPERATION_POWER_ON    = 1;
6
  POWER_SHELF_MAINTENANCE_OPERATION_POWER_OFF   = 2;
7
}
8
9
message PowerShelfMaintenanceRequest {
10
  repeated common.PowerShelfId power_shelf_ids = 1;
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  PowerShelfMaintenanceOperation operation = 2;
12
  optional string reference = 3;
13
}

Validation rules enforced by the API handler:

• power_shelf_ids must contain at least one ID and at most runtime_config.max_find_by_ids IDs.
• operation must be POWER_ON or POWER_OFF; UNSPECIFIED is rejected with InvalidArgument.
• Every listed power shelf must exist and must not be marked for deletion; otherwise the entire transaction is rolled back.

The handler runs all updates in a single database transaction, so a caller observes the new maintenance request on every listed shelf simultaneously (or not at all).

Initiator string

The DB column power_shelf_maintenance_requested stores who/why requested the operation. The API composes it from two sources:

Data model

The power_shelves.power_shelf_maintenance_requested column is a nullable JSONB; the API sets it on SetPowerShelfMaintenance and the state controller clears it when the operation finishes

Notes / Status

• The state machine and request plumbing (CLI → gRPC → DB → state controller → state transition) are implemented end-to-end.
• The actual BMC / PMC call inside the Maintenance handler is still a TODO: today the handler clears the maintenance request and returns to Ready without driving the hardware. Plugging in the real PowerOn / PowerOff BMC action is a focused follow-up that does not change the public CLI / gRPC surface.