delete relation

Deletes relations from the message originator based on configured direction, type, and optional target entity.

Configuration

Direction: Defines the direction of relations to delete from the message originator.
- From originator: Deletes relations where the message originator is the “from” entity
- To originator: Deletes relations where the message originator is the “to” entity
Relation type: Type of relations to delete. Supports templatization using ${metadataKey} and $[dataKey] patterns.
Delete relation with specific entity: When enabled, deletes relation only with the specified target entity. When disabled, deletes all relations of the specified type and direction.

Target entity configuration (when Delete relation with specific entity is enabled)

Type: Type of target entity to delete relation with.
Entity identifier: Name, title, or email of the target entity (depends on entity type). Supports templatization using ${metadataKey} and $[dataKey] patterns.

Supported target entity types:

Device, Asset, Entity View, Edge, Converter, Role - specify name as entity identifier
Customer, Dashboard - specify title as entity identifier
User - specify email as entity identifier
Tenant - no identifier needed (uses current tenant)

JSON Schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "TbDeleteRelationNodeConfiguration",
  "type": "object",
  "properties": {
    "direction": {
      "type": "string",
      "enum": [
        "FROM",
        "TO"
      ],
      "description": "Direction of relations to delete"
    },
    "relationType": {
      "type": "string",
      "description": "Type of relations to delete"
    },
    "deleteForSingleEntity": {
      "type": "boolean",
      "description": "Whether to delete relation with specific entity only"
    },
    "entityType": {
      "type": "string",
      "enum": [
        "TENANT",
        "DEVICE",
        "ASSET",
        "CUSTOMER",
        "ENTITY_VIEW",
        "DASHBOARD",
        "USER",
        "EDGE",
        "CONVERTER",
        "ROLE"
      ],
      "description": "Target entity type (when 'deleteForSingleEntity' is true)"
    },
    "entityNamePattern": {
      "type": "string",
      "description": "Target entity name/title/email pattern (when 'deleteForSingleEntity' is true)"
    }
  }
}

Message processing algorithm

Process relation type: Processes the configured relation type pattern, substituting any placeholders with values from the message.
Determine deletion mode:
- If Delete relation with specific entity is enabled, proceeds to specific entity deletion
- If disabled, proceeds to delete all relations of the specified type and direction
Specific entity deletion (when Delete relation with specific entity is enabled):
- Processes the target entity identifier pattern, substituting placeholders with message values
- Looks up the target entity by type and processed identifier (processing fails if entity doesn’t exist)
- Deletes the relation of specified type and direction between message originator and target entity
Bulk deletion (when Delete relation with specific entity is disabled):
- Deletes all relations of the specified type and direction involving the message originator
Route message: Routes the original message to Success if all deletions were successful, otherwise to Failure.

Output connections

Success
- All relations of the specified type and direction involving the message originator were successfully deleted
- Relation of specified type and direction between message originator and target entity was deleted
Failure
- Target entity was not found
- Unexpected error occurred during processing

Examples

Example 1 — Delete all relations of specific type

Incoming message

Any message.

Node configuration

{
  "direction": "FROM",
  "relationType": "Contains",
  "deleteForSingleEntity": false
}

State of the system

Following relations exist:

From originator with type Contains to Device A, Device B, and Device C.
From originator with type Uses to Asset D

Outgoing message

Same as incoming message, routed via Success connection.

Result

All Contains relations from the originator are deleted (relations to Device A, Device B, and Device C). The Uses relation to Asset D remains unchanged.

Example 2 — Delete relation with specific entity using patterns

Incoming message

Originator: DEVICE

Data:

{
  "targetAssetName": "Building"
}

Metadata:

{
  "relationType": "LocatedIn"
}

Node configuration

{
  "direction": "FROM",
  "relationType": "${relationType}",
  "deleteForSingleEntity": true,
  "entityType": "ASSET",
  "entityNamePattern": "$[targetAssetName]"
}

State of the system

Following relations exist:

From originator device with type LocatedIn to asset named Building.
From originator with various type to other assets.

Outgoing message

Same as incoming message, routed via Success connection.

Result

The LocatedIn relation between originator device and asset Building is deleted. All other relations remain unchanged.

Example 3 — Delete relation with tenant

Incoming message

Any message.

Node configuration

{
  "direction": "TO",
  "relationType": "Owns",
  "deleteForSingleEntity": true,
  "entityType": "TENANT"
}

State of the system

Following relation exist:

From current tenant with type Owns to the originator.

Outgoing message

Same as incoming message, routed via Success connection.

Result

The Owns relation from the tenant to originator device is deleted. Note that there is no need to specify an entity identifier since there is only one tenant to choose from: the current tenant.

Example 4 — Attempt to delete relation with non-existent entity

Incoming message

Any message.

Node configuration

{
  "direction": "FROM",
  "relationType": "Contains",
  "deleteForSingleEntity": true,
  "entityType": "ASSET",
  "entityNamePattern": "nonexistent_asset"
}

State of the system

No asset named nonexistent_asset exists in the system.

Outgoing message

Same as incoming message, routed via Failure connection.

Result

Processing fails because target entity does not exist. No relations are modified.