Skip to content
HomeARM Emulator

Microsoft.Fabric/capacities

Fabric capacities are ARM resources. The Fabric REST plane (api.fabric.microsoft.com) only lists them and assigns workspaces; create, SKU, suspend and resume happen on management.azure.com. This is that ARM half. fabric-emulator consumes it over the family feed.

PUT    /subscriptions/{s}/resourceGroups/{rg}/providers/Microsoft.Fabric/capacities/{name}
GET    …/capacities/{name}
PATCH  …/capacities/{name}
DELETE …/capacities/{name}
GET    …/capacities                       (by resource group)
GET    /subscriptions/{s}/providers/Microsoft.Fabric/capacities   (by subscription)
POST   …/capacities/{name}/suspend
POST   …/capacities/{name}/resume
GET    …/capacities/{name}/skus
GET    /subscriptions/{s}/providers/Microsoft.Fabric/skus
POST   /subscriptions/{s}/providers/Microsoft.Fabric/locations/{loc}/checkNameAvailability
GET    /subscriptions/{s}/providers/Microsoft.Fabric/locations/{loc}/usages

Creation

Section titled “Creation”

A capacity must be created inside an existing resource group — creating into a missing group returns ResourceGroupNotFound. The name is 3–63 lowercase alphanumeric characters starting with a letter, as the REST reference requires. sku.name is an F-series SKU (F2…F2048), sku.tier is Fabric, and properties.administration.members is required.

Real ARM runs create, update, suspend, resume and delete as long-running operations. The emulator answers with the same headers the SDKs poll (Azure-AsyncOperation on PUT/PATCH, Location on DELETE/suspend/resume) and completes them on the controllable clock. With the default zero delay the first poll is already terminal, which is what armfabric, azure-mgmt-fabric, @azure/arm-fabric and Azure.ResourceManager.Fabric accept.

A new capacity is assigned a Fabric REST GUID at create. ARM’s own document does not carry it — Azure doesn’t either — so it travels on the family feed instead of being invented twice.

What this does not do

Section titled “What this does not do”

SKU is an assignable label and a CU count for list_usages. There is no billing, no job metering, and no throttling. properties.overage round-trips (Enabled/Disabled and the threshold) and does nothing else. list_usages reports provisioned F-SKU CU in the location, not consumed compute: an F64 that has never run a notebook still counts as 64. A paused capacity counts as zero.

That is the honest split: the ARM resource is real, the capacity as a compute bound is still fabric-emulator’s unbuilt job-queueing work.

The family feed

Section titled “The family feed”
GET /_family/capacities

Unauthenticated, like /_family/authorization. The document is every capacity this process holds, with the Fabric REST id, the ARM resource id, SKU, region, state and admins. fabric-emulator polls it and upserts those rows into GET /v1/capacities.