State Updater Agent

The State Updater Agent synchronizes local entity states with the NGSI-LD context broker (Stellio).

📋 Overview

Property	Value
Module	src.agents.context_management.state_updater_agent
Class	StateUpdaterAgent
Author	UIP Team
Version	1.0.0

🎯 Purpose

• Synchronize entity states with Stellio context broker
• Batch updates for efficiency
• Handle conflicts and version management
• Maintain consistency between local and remote state

🚀 Usage

Update Entity State

from src.agents.context_management.state_updater_agent import StateUpdaterAgent

updater = StateUpdaterAgent()

# Update single entity
await updater.update(
    entity_id="urn:ngsi-ld:TrafficCamera:CAM_001",
    attributes={
        "status": {"value": "active"},
        "vehicleCount": {"value": 42}
    }
)

Batch Updates

# Batch update multiple entities
updates = [
    {
        "id": "urn:ngsi-ld:TrafficCamera:CAM_001",
        "status": {"value": "active"}
    },
    {
        "id": "urn:ngsi-ld:TrafficCamera:CAM_002",
        "status": {"value": "offline"}
    }
]

result = await updater.batch_update(updates)
print(f"Updated: {result['success']}, Failed: {result['failed']}")

Upsert Pattern

# Create or update entity
await updater.upsert(
    entity={
        "id": "urn:ngsi-ld:TrafficCamera:CAM_003",
        "type": "TrafficCamera",
        "location": {
            "type": "GeoProperty",
            "value": {"type": "Point", "coordinates": [106.6297, 10.8231]}
        }
    }
)

⚙️ Configuration

# config/state_updater_config.yaml
state_updater:
  enabled: true
  
  # Stellio connection
  stellio:
    url: "http://localhost:8080"
    tenant: "urn:ngsi-ld:tenant:hcmc"
  
  # Batch settings
  batch:
    size: 100
    timeout_seconds: 30
    retry_failed: true
  
  # Conflict resolution
  conflict:
    strategy: "last-write-wins"  # last-write-wins, merge, reject
    timestamp_field: "modifiedAt"
  
  # Update mode
  update:
    mode: "patch"  # patch, replace
    include_observed_at: true

🔄 Update Modes

Mode	Description	Use Case
patch	Update only specified attributes	Incremental updates
replace	Replace all attributes	Full state sync
append	Add to multi-valued attributes	Historical data

📖 Related Documentation

• Entity Publisher - Entity creation
• Stellio State Query - Query operations
• NGSI-LD Transformer - Entity format

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See the complete agents reference for all available agents.