Dual-licensed. Splice is available under the GNU AGPL v3.0-or-later (free, copyleft — see LICENSE) or a commercial licence for proprietary / closed-source use (see COMMERCIAL-LICENSE.md, contact infoknex@tcd.ie). Details ↓

The Problem

Modern telemetry collectors — gnmic, Telegraf, OpenConfig pipelines — expect gNMI over gRPC. But a huge amount of deployed optical and transport gear only speaks NETCONF: ROADMs, transponders, amplifiers, line systems. Each vendor ships its own YANG models, its own list keys, its own quirks. Bolting a collector onto them usually means writing per-device glue and re-writing it every firmware bump.

This bridge fixes that. Give it an IP and credentials; it discovers the device's YANG models, builds a telemetry catalog, polls NETCONF under the hood, and serves standard gNMI to any client — no per-vendor code, no changes to the device.

How It Works

graph LR
    D["NETCONF device<br/>:830 (SSH)"] -->|YANG discovery| C[Catalog]
    C --> P[Poller]
    P -->|NETCONF get| D
    P --> M[(TTL cache)]
    M --> G["gNMI server<br/>:9339 (gRPC)"]
    G -->|gNMI Get / Subscribe| K["gnmic · Telegraf<br/>AI agents"]
    DB[(PostgreSQL)] -.-> C

Discovery walks the device's YANG library into module-qualified catalog paths, the planner batches them into efficient NETCONF reads, and a resilient poller fills a TTL cache that the gRPC server answers from. Performance-monitoring data is published under synthetic, instance-keyed paths so per-port metrics never collide.

✨ Key Features

Resilience is the load-bearing design choice: optical devices frequently limit concurrent NETCONF sessions and lock accounts on repeated auth failures, so every RPC path is built to back off rather than hammer.

Quick Start

1. Install

python -m venv .venv && source .venv/bin/activate
pip install splice-gnmi              # core CLI + gNMI server
pip install "splice-gnmi[tui]"       # optional: interactive console
pip install "splice-gnmi[mcp]"       # optional: AI-agent interface

The package is called splice-gnmi on PyPI; the command and the Python import are both splice. To work on Splice itself, install from a clone instead (see Development).

2. Try it with no hardware

splice --simulate openroadm run

In another terminal, it answers gNMI like any real server:

gnmic -a localhost:9339 --insecure capabilities
# gNMI version: 0.8.0
# supported models:
#   - org-openroadm-device, 2023-05-26  ...

Or read live values straight from the simulated device via the Python API:

from splice.api.device import Device

with Device("sim://openroadm") as dev:
    print(dev.get("/org-openroadm-device/node-id"))
    # [{'path': '/org-openroadm-device/node-id', 'value': 'ROADM-SIM-01'}]

3. Point it at a real device

NETCONF_PASSWORD='...' splice quickstart --host 10.0.0.1 --username admin

This generates a per-device config, runs full discovery, writes Grafana dashboards for the device, and starts the gNMI server. That's the whole promise — an IP in, a gNMI endpoint out.

Four Ways to Use It

Configuration

YAML-based, one file per device. Credentials come from the NETCONF_PASSWORD env var or a password_file — never committed.

device:
  host: 10.0.0.1
  username: admin
  password_file: devices/my_device/password
gnmi:
  port: 9339
  expansion_mode: direct      # use cached list instances (safe default)
poller:
  default_interval_sec: 30
  task_failure_limit: 5       # drop a path after N consecutive failures
metrics:                      # optional: poll only what you care about
  enabled: true
  include:
    - { pattern: "opt-rcv-pwr|fec-ber", regex: true, interval_sec: 5 }

See docs/configuration.md for the full reference.

Documentation

Development

git clone https://github.com/Open-Ireland-Testbed/splice.git
cd splice
python -m venv .venv && source .venv/bin/activate
pip install -e ".[tui,mcp,search]"

python -m pytest                                    # ~640 tests, no DB needed
TEST_DATABASE_URL='postgresql+psycopg://postgres:postgres@localhost:5432/splice' \
  python -m pytest                                  # include PostgreSQL-backed tests

CI runs the migration-safety, no-database, and full PostgreSQL 16 suites on every push.

Licensing

Splice is dual-licensed:

1. GNU AGPL v3.0-or-later (see LICENSE) — free for open-source and AGPL-compliant use. If you modify Splice or run it as a network service, the AGPL requires you to make your corresponding source available to its users.
2. Commercial licence — for proprietary, embedded, or closed-source use without the AGPL's copyleft obligations. See COMMERCIAL-LICENSE.md for a summary.

If you use Splice in a closed-source or commercial product, you must obtain a commercial licence. To request one, contact Trinity College Dublin (Trinity Innovation & Enterprise) at infoknex@tcd.ie.

Copyright (c) 2026 Trinity College Dublin. Splice bundles and depends on third-party open-source components (gRPC, ncclient, SQLAlchemy, pyang, paramiko, the OpenConfig gNMI definitions, and others) under their own permissive or LGPL licences; none of those impose copyleft on Splice or constrain this dual-license choice.