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Sinks

Sinks are destinations for join and window results. LiteJoin evaluates your SQL queries and forwards matching results to one or more configured sinks.

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HTTP Webhook

Sends results as JSON POST requests to a URL. 
sinks:
  - type: http
    name: webhook-out
    config:
      url: "http://localhost:9000/webhook"
      timeout: "30s"
FieldTypeDefaultDescription
urlstringrequiredWebhook URL to POST results to.
timeoutduration30sRequest timeout.
Results are sent as JSON in the request body.

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Kafka

Produces results as messages to a Kafka topic. 
sinks:
  - type: kafka
    name: kafka-out
    config:
      brokers: "localhost:9092"
      topic: "joined-events"
FieldTypeDefaultDescription
brokersstringrequiredComma-separated broker addresses.
topicstringrequiredTarget Kafka topic.

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SSE (Server-Sent Events)

Streams results to browser clients via Server-Sent Events. Ideal for real-time dashboards and UIs. 
sinks:
  - type: sse
    name: dashboard
    config:
      addr: ":9100"
FieldTypeDefaultDescription
addrstringrequiredAddress to listen on.

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Endpoints

The SSE sink exposes three HTTP endpoints:
EndpointMethodDescription
/subscribeGETOpens an SSE stream. Use ?join=name to filter by join or ?join=* for all.
/snapshotGETReturns a JSON snapshot of current results. See Snapshot API.
/healthGETHealth check — returns {"status": "ok"}.

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Browser Example

const es = new EventSource('http://localhost:9100/subscribe?join=*');

es.addEventListener('join_result', (event) => {
  const result = JSON.parse(event.data);
  console.log(result.query, result.key, result.rows);
});

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Replay on Connect

Add ?replay=true to receive a snapshot of current results as SSE events before switching to live streaming: 
const es = new EventSource('http://localhost:9100/subscribe?join=*&replay=true');
Replay events include "_replay": true so your client can distinguish initial state from live updates.

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SQLite

Writes results to a local SQLite database for querying by external apps. 
sinks:
  - type: sqlite
    name: local-db
    config:
      path: "./output/results.db"
FieldTypeDefaultDescription
pathstringrequiredPath to the SQLite database file.

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Routing Joins to Sinks

Each join or window specifies its target sink by name: 
joins:
  - name: order-enrichment
    query: |
      SELECT ...
    sink: webhook-out    # ← references the sink name

sinks:
  - type: http
    name: webhook-out    # ← matched by name
    config:
      url: "http://example.com/webhook"
Multiple joins can route to the same sink, and you can configure multiple sinks of different types.