# getSubscriptionTopic API

Builds the MQTT topic filter for a PURISTA subscription definition.

---
Canonical: /handbook/api/variables/_purista_mqttbridge.getSubscriptionTopic/
Source: mqttbridge/src/topic/getSubscriptionTopic.impl.ts
Format: Markdown for agents
---

Builds the MQTT topic filter for a PURISTA subscription definition.

Package: `@purista/mqttbridge`

## Signature

```typescript
const getSubscriptionTopic: GetSubscriptionTopicFn
```