seedlink-client

SeedLink protocol client for streaming geophysical (primarily seismic) data, with transparent support for both SeedLink 3.x and 4.0. SeedLink is a real-time streaming protocol used by seismological data systems (e.g. SeisComP, EarthScope's ringserver) to deliver miniSEED data as it is recorded.

Requires Python 3.11+.

Installation

pip install seedlink-client

Usage

Sync API

from seedlink_client import SeedLink

with SeedLink("rtserve.earthscope.org") as sl:
    sl.add_stream("IU_COLA", "BH?")
    for packet in sl.collect():
        print(packet.station_id, packet.seqnum, len(packet.payload))

Async API

AsyncSeedLink offers the same API as SeedLink, built on asyncio. Only the methods that do network I/O (connect, collect, info, ...) are coroutines; stream selection (add_stream and friends) is plain configuration and stays synchronous on both clients:

import asyncio
from seedlink_client import AsyncSeedLink

async def main():
    async with AsyncSeedLink("rtserve.earthscope.org") as sl:
        sl.add_stream("IU_COLA", "BH?")
        async for packet in sl.collect():
            print(packet.station_id, packet.seqnum, len(packet.payload))

asyncio.run(main())

Protocol versions

SeedLink/AsyncSeedLink negotiate SeedLink 3.x or 4.0 automatically from the server's HELLO reply and speak whichever is offered -- selectors, sequence numbers, time windows, and INFO queries all work the same way from the caller's side regardless of which protocol is in use. Pass protocol=Protocol.V3 or Protocol.V4 to pin a version instead of negotiating.

Packets carry their payload as raw bytes; call packet.record() to decode it as a pymseed MS3Record.

Command-line client

A non-interactive client is available after install:

seedlink-client [host:port]

Default is localhost:18000. Use seedlink-client --help for options (stream selection, time windows, state files, INFO queries, TLS, auth). Pass -c/--interactive for a low-level interactive shell that sends individual protocol commands (HELLO, SLPROTO, STATION, SELECT, DATA, INFO, ...) -- unlike the non-interactive client, it does not send HELLO or negotiate a protocol version on its own; type HELLO, then SLPROTO 4.0 to upgrade if the server supports v4 (HELP shows a full example). END (or, in v3 uni-station mode, DATA/FETCH/TIME with no prior STATION) finishes the handshake and starts printing packets as they arrive, until Enter or Ctrl-C.