nats_js

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nats_js

Downloads 798this week

GitHub stars 19

Extension repository on GitHub

Extension descriptor (YAML)

Query NATS JetStream message streams directly with SQL

Maintainer(s): brannn

Installing and Loading

INSTALL nats_js FROM community;
LOAD nats_js;

Example

-- Query messages from a NATS JetStream stream
SELECT subject, seq, ts_nats, payload
FROM nats_scan('telemetry')
WHERE seq BETWEEN 1 AND 100;

-- Extract JSON fields with dot notation
SELECT device_id, zone, kw
FROM nats_scan('telemetry',
    json_extract := ['device_id', 'zone', 'kw']
);

-- Extract Protocol Buffers fields with nested navigation
SELECT device_id, location_zone, metrics_kw
FROM nats_scan('telemetry',
    proto_file := 'telemetry.proto',
    proto_message := 'Telemetry',
    proto_extract := ['device_id', 'location.zone', 'metrics.kw']
);

About nats_js

The NATS JetStream extension enables direct SQL querying of NATS JetStream message streams without establishing durable consumers.

Features:

Sequence-based range queries (start_seq, end_seq)
Timestamp-based range queries with binary search (start_time, end_time)
Subject filtering for targeted message retrieval
JSON payload extraction with dot notation for nested fields
Protocol Buffers support with runtime schema parsing and nested message navigation

Perfect for ETL workflows, analytics, and ad-hoc querying of message streams.

GitHub: https://github.com/brannn/duckdb-nats-jetstream