Managing Device Assignments

An assignment relates a device to a customer, area or asset, so its telemetry carries organizational context. In DeviceChain an assignment is a tracked relationship on the uniform entity graph. There is no separate assignment record.

Status

Available. Manage assignments from the Assignment tab on the device detail page in the console, or over the device-management GraphQL API.

Assignment organizes; it does not gate

A device authenticates with a credential. Assignment only organizes its data, and the two are independent:

• A registered, credentialed device reports telemetry immediately, even with no assignment. Its events resolve with an empty anchor set: they still persist and still update the device's live state, but they are not yet attributed to a customer, area or asset.
• Assigning the device later gives its subsequent events an anchor (on every device-management replica; a replica that missed the change notice catches up when its cached copy expires, within five minutes by default), so queries such as "every reading for Building 7" find them.

Unassigned devices are therefore never silently dropped. This is a change from earlier behavior.

Every assignment is an anchor

A device may hold several assignments at once: a customer, an area and an asset. When the device reports an event, each assignment is recorded as an anchor on that event. The same reading is then queryable by every dimension; it shows up under the customer and under the area. No assignment is primary — they are equal.

Each event's anchors live in a sibling event_anchors set, one row per assignment. An anchor-filtered query ("events for area Y") matches events whose set contains that anchor.

Anchors are captured at write time, so history is stable. A device that later moves areas keeps, on each old event, the area it was in when that event happened.

Assign a device (console)

1. Open the device's detail page and select the Assignment tab.
2. Choose a target type (Customer / Area / Asset) and pick the target entity.
3. Click Assign.
4. Repeat to add more assignments. The device can be assigned to several targets at once.

To unassign, click Unassign on a row. The device's future events stop being anchored to that target; events already recorded keep their anchors.

Assign a device (GraphQL)

An assignment is a relationship edge of the reserved assigned type. This is a built-in tracked type, provisioned automatically per tenant on first use. Create one with the bulk mutation, addressing source and target by (type, token):

mutation {
  createEntityRelationships(requests: [{
    token: "3f1c…",            # a fresh unique edge token (e.g. a UUID)
    sourceType: "device",
    source: "sensor-001",       # device token
    targetType: "customer",     # customer | area | asset
    target: "lucidworks",       # target entity token
    relationshipType: "assigned"
  }]) { id token }
}

List a device's assignments by querying its tracked edges of the assigned type:

query {
  entityRelationships(criteria: {
    sourceType: "device", source: "sensor-001",
    relationshipType: "assigned", pageNumber: 1, pageSize: 100
  }) {
    results { id token targetType target { token } }
  }
}

Remove one with removeEntityRelationships(tokens: ["<edge token>"]).

Creating and removing assignments requires the device:write authority. Listing them requires device:read.

Relationship vs. assignment

Assignment is one use of the general relationship graph. The same createEntityRelationships and removeEntityRelationships mutations back group membership (the reserved untracked member type) and any custom relationship type you define. What makes a relationship an assignment that anchors events is that its type is tracked. See the Domain Model.