Files
weave-scope/examples/plugins/volume-count/5-querying-prometheus.py
2016-10-05 11:44:34 +01:00

110 lines
3.1 KiB
Python
Executable File

#!/usr/bin/env python
import BaseHTTPServer
import SocketServer
import datetime
import errno
import json
import os
import signal
import socket
import urllib2
PLUGIN_ID="prometheus"
PLUGIN_UNIX_SOCK = "/var/run/scope/plugins/" + PLUGIN_ID + ".sock"
METRIC_NAME="http_requests_per_second"
METRIC_LABEL="HTTP req/sec"
METRIC_CONTAINER_ID_KEY="container_id"
PROMETHEUS_ADDR="prometheus.monitoring.svc.cluster.local"
def metrics():
r = urllib2.urlopen("http://%s/api/v1/query?query=%s" % (PROMETHEUS_ADDR, METRIC_NAME))
return json.loads(r.content).get("data", default={}).get("result", default=[])
class Handler(BaseHTTPServer.BaseHTTPRequestHandler):
def do_GET(self):
# The logger requires a client_address, but unix sockets don't have
# one, so we fake it.
self.client_address = "-"
# Fetch and convert data from prometheus
nodes = {}
for metric in metrics():
container_id = metric.get("metric", default={}).get(METRIC_CONTAINER_ID_KEY, default=None)
if container_id == None:
continue
nodes["%s;<container>" % (container_id)] = {
'metrics': {
METRIC_NAME: {
'samples': [{
'date': datetime.datetime.utcfromtimestamp(metric["value"][0]).isoformat('T') + 'Z',
'value': float(metric["value"][1]),
}]
}
}
}
# Generate our json body
body = json.dumps({
'Plugins': [
{
'id': PLUGIN_ID,
'label': 'Prometheus data translator',
'description': 'Takes data from prometheus and puts it into scope',
'interfaces': ['reporter'],
'api_version': '1',
}
],
'Container': {
'nodes': nodes,
'metric_templates': {
METRIC_NAME: {
'id': METRIC_NAME,
'label': METRIC_LABEL,
'priority': 0.1,
}
}
},
})
# Send the headers
self.send_response(200)
self.send_header('Content-type', 'application/json')
self.send_header('Content-length', len(body))
self.end_headers()
# Send the body
self.wfile.write(body)
def mkdir_p(path):
try:
os.makedirs(path)
except OSError as exc:
if exc.errno == errno.EEXIST and os.path.isdir(path):
pass
else:
raise
def delete_socket_file():
if os.path.exists(PLUGIN_UNIX_SOCK):
os.remove(PLUGIN_UNIX_SOCK)
def sig_handler(b, a):
delete_socket_file()
exit(0)
def main():
signal.signal(signal.SIGTERM, sig_handler)
signal.signal(signal.SIGINT, sig_handler)
mkdir_p(os.path.dirname(PLUGIN_UNIX_SOCK))
delete_socket_file()
server = SocketServer.UnixStreamServer(PLUGIN_UNIX_SOCK, Handler)
try:
server.serve_forever()
except:
delete_socket_file()
raise
main()