snappi 0.11.1

The Snappi Open Traffic Generator Python Package

Test scripts written in snappi, an auto-generated python SDK, can be executed against any traffic generator conforming to Open Traffic Generator API.

Ixia-c is one such reference implementation of Open Traffic Generator API.

The repository is under active development and is subject to updates. All efforts will be made to keep the updates backwards compatible.

Setup Client

python -m pip install --upgrade snappi

Start Testing

import datetime
import time
import snappi
import pytest


@pytest.mark.example
def test_quickstart():
    # Create a new API handle to make API calls against OTG
    # with HTTP as default transport protocol
    api = snappi.api(location="https://localhost:8443")

    # Create a new traffic configuration that will be set on OTG
    config = api.config()

    # Add a test port to the configuration
    ptx = config.ports.add(name="ptx", location="veth-a")

    # Configure a flow and set previously created test port as one of endpoints
    flow = config.flows.add(name="flow")
    flow.tx_rx.port.tx_name = ptx.name
    # and enable tracking flow metrics
    flow.metrics.enable = True

    # Configure number of packets to transmit for previously configured flow
    flow.duration.fixed_packets.packets = 100
    # and fixed byte size of all packets in the flow
    flow.size.fixed = 128

    # Configure protocol headers for all packets in the flow
    eth, ip, udp, cus = flow.packet.ethernet().ipv4().udp().custom()

    eth.src.value = "00:11:22:33:44:55"
    eth.dst.value = "00:11:22:33:44:66"

    ip.src.value = "10.1.1.1"
    ip.dst.value = "20.1.1.1"

    # Configure repeating patterns for source and destination UDP ports
    udp.src_port.values = [5010, 5015, 5020, 5025, 5030]
    udp.dst_port.increment.start = 6010
    udp.dst_port.increment.step = 5
    udp.dst_port.increment.count = 5

    # Configure custom bytes (hex string) in payload
    cus.bytes = "".join([hex(c)[2:] for c in b"..QUICKSTART SNAPPI.."])

    # Optionally, print JSON representation of config
    print("Configuration: ", config.serialize(encoding=config.JSON))

    # Push traffic configuration constructed so far to OTG
    api.set_config(config)

    # Start transmitting the packets from configured flow
    ts = api.transmit_state()
    ts.state = ts.START
    api.set_transmit_state(ts)

    # Fetch metrics for configured flow
    req = api.metrics_request()
    req.flow.flow_names = [flow.name]
    # and keep polling until either expectation is met or deadline exceeds
    start = datetime.datetime.now()
    while True:
        metrics = api.get_metrics(req)
        if (datetime.datetime.now() - start).seconds > 10:
            raise Exception("deadline exceeded")
        # print YAML representation of flow metrics
        print(metrics)
        if metrics.flow_metrics[0].transmit == metrics.flow_metrics[0].STOPPED:
            break
        time.sleep(0.1)