core/tests/components/prometheus/test_init.py

"""The tests for the Prometheus exporter."""
import asyncio
import pytest

from homeassistant.setup import async_setup_component
import homeassistant.components.prometheus as prometheus


@pytest.fixture
def prometheus_client(loop, hass, hass_client):
    """Initialize an hass_client with Prometheus component."""
    assert loop.run_until_complete(
        async_setup_component(hass, prometheus.DOMAIN, {prometheus.DOMAIN: {}})
    )
    return loop.run_until_complete(hass_client())


@asyncio.coroutine
def test_view(prometheus_client):  # pylint: disable=redefined-outer-name
    """Test prometheus metrics view."""
    resp = yield from prometheus_client.get(prometheus.API_ENDPOINT)

    assert resp.status == 200
    assert resp.headers["content-type"] == "text/plain"
    body = yield from resp.text()
    body = body.split("\n")

    assert len(body) > 3  # At least two comment lines and a metric
    for line in body:
        if line:
            assert (
                line.startswith("# ")
                or line.startswith("process_")
                or line.startswith("python_info")
            )