"""
HTTP API for Proxmox VE prometheus collector.
"""
import logging
import time
from prometheus_client import CONTENT_TYPE_LATEST, Summary, Counter, generate_latest
from werkzeug.routing import Map, Rule
from werkzeug.serving import run_simple
from werkzeug.wrappers import Request, Response
from werkzeug.exceptions import InternalServerError
from .collector import collect_pve
class PveExporterApplication(object):
"""
Proxmox VE prometheus collector HTTP handler.
"""
# pylint: disable=no-self-use
def __init__(self, config, duration, errors):
self._config = config
self._duration = duration
self._errors = errors
self._url_map = Map([
Rule('/', endpoint='index'),
Rule('/metrics', endpoint='metrics'),
Rule('/pve', endpoint='pve'),
])
self._args = {
'pve': ['module', 'target']
}
self._views = {
'index': self.on_index,
'metrics': self.on_metrics,
'pve': self.on_pve,
}
self._log = logging.getLogger(__name__)
def on_pve(self, module='default', target='localhost'):
"""
Request handler for /pve route
"""
if module in self._config:
start = time.time()
output = collect_pve(self._config[module], target)
response = Response(output)
response.headers['content-type'] = CONTENT_TYPE_LATEST
self._duration.labels(module).observe(time.time() - start)
else:
response = Response("Module '{0}' not found in config".format(module))
response.status_code = 400
return response
def on_metrics(self):
"""
Request handler for /metrics route
"""
response = Response(generate_latest())
response.headers['content-type'] = CONTENT_TYPE_LATEST
return response
def on_index(self):
"""
Request handler for index route (/).
"""
response = Response(
"""<html>
<head><title>Proxmox VE Exporter</title></head>
<body>
<h1>Proxmox VE Exporter</h1>
<p>Visit <code>/pve?target=1.2.3.4</code> to use.</p>
</body>
</html>"""
)
response.headers['content-type'] = 'text/html'
return response
def view(self, endpoint, values, args):
"""
Werkzeug views mapping method.
"""
params = dict(values)
if endpoint in self._args:
params.update({key: args[key] for key in self._args[endpoint] if key in args})
try:
return self._views[endpoint](**params)
except Exception as error: # pylint: disable=broad-except
self._log.exception("Exception thrown while rendering view")
self._errors.labels(args.get('module', 'default')).inc()
raise InternalServerError(error)
@Request.application
def __call__(self, request):
urls = self._url_map.bind_to_environ(request.environ)
view_func = lambda endpoint, values: self.view(endpoint, values, request.args)
return urls.dispatch(view_func, catch_http_exceptions=True)
def start_http_server(config, port, address=''):
"""
Start a HTTP API server for Proxmox VE prometheus collector.
"""
duration = Summary(
'pve_collection_duration_seconds',
'Duration of collections by the PVE exporter',
['module'],
)
errors = Counter(
'pve_request_errors_total',
'Errors in requests to PVE exporter',
['module'],
)
# Initialize metrics.
for module in config.keys():
# pylint: disable=no-member
errors.labels(module)
# pylint: disable=no-member
duration.labels(module)
app = PveExporterApplication(config, duration, errors)
run_simple(address, port, app, threaded=True)
