#!/usr/bin/python

from __future__ import unicode_literals

import os

import socket

import time

import threading

from contextlib import closing

from wsgiref.simple_server import make_server

from . import core

try:

from BaseHTTPServer import BaseHTTPRequestHandler

from BaseHTTPServer import HTTPServer

from urllib2 import build_opener, Request, HTTPHandler

from urllib import quote_plus

from urlparse import parse_qs, urlparse

except ImportError:

# Python 3

unicode = str

from http.server import BaseHTTPRequestHandler

from http.server import HTTPServer

from urllib.request import build_opener, Request, HTTPHandler

from urllib.parse import quote_plus, parse_qs, urlparse

CONTENT_TYPE_LATEST = str('text/plain; version=0.0.4; charset=utf-8')

'''Content type of the latest text format'''

def make_wsgi_app(registry=core.REGISTRY):

'''Create a WSGI app which serves the metrics from a registry.'''

def prometheus_app(environ, start_response):

params = parse_qs(environ['QUERY_STRING'])

r = registry

if 'name[]' in params:

r = r.restricted_registry(params['name[]'])

output = generate_latest(r)

status = str('200 OK')

headers = [(str('Content-type'), CONTENT_TYPE_LATEST)]

start_response(status, headers)

return [output]

return prometheus_app

def start_wsgi_server(port, addr='', registry=core.REGISTRY):

"""Starts a WSGI server for prometheus metrics as a daemon thread."""

class PrometheusMetricsServer(threading.Thread):

def run(self):

httpd = make_server(addr, port, make_wsgi_app(registry))

httpd.serve_forever()

t = PrometheusMetricsServer()

t.daemon = True

t.start()

def generate_latest(registry=core.REGISTRY):

'''Returns the metrics from the registry in latest text format as a string.'''

output = []

for metric in registry.collect():

output.append('# HELP {0} {1}'.format(

metric.name, metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))

output.append('\n# TYPE {0} {1}\n'.format(metric.name, metric.type))

for name, labels, value in metric.samples:

if labels:

labelstr = '{{{0}}}'.format(','.join(

['{0}="{1}"'.format(

k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))

for k, v in sorted(labels.items())]))

else:

labelstr = ''

output.append('{0}{1} {2}\n'.format(name, labelstr, core._floatToGoString(value)))

return ''.join(output).encode('utf-8')

class MetricsHandler(BaseHTTPRequestHandler):

def do_GET(self):

registry = core.REGISTRY

params = parse_qs(urlparse(self.path).query)

if 'name[]' in params:

registry = registry.restricted_registry(params['name[]'])

try:

output = generate_latest(registry)

except:

self.send_error(500, 'error generating metric output')

raise

self.send_response(200)

self.send_header('Content-Type', CONTENT_TYPE_LATEST)

self.end_headers()

self.wfile.write(output)

def log_message(self, format, *args):

return

def start_http_server(port, addr=''):

"""Starts a HTTP server for prometheus metrics as a daemon thread."""

class PrometheusMetricsServer(threading.Thread):

def run(self):

httpd = HTTPServer((addr, port), MetricsHandler)

httpd.serve_forever()

t = PrometheusMetricsServer()

t.daemon = True

t.start()

def write_to_textfile(path, registry):

'''Write metrics to the given path.

This is intended for use with the Node exporter textfile collector.

The path must end in .prom for the textfile collector to process it.'''

tmppath = '%s.%s.%s' % (path, os.getpid(), threading.current_thread().ident)

with open(tmppath, 'wb') as f:

f.write(generate_latest(registry))

# rename(2) is atomic.

os.rename(tmppath, path)

def push_to_gateway(gateway, job, registry, grouping_key=None, timeout=None):

'''Push metrics to the given pushgateway.

`gateway` the url for your push gateway. Either of the form

'http://pushgateway.local', or 'pushgateway.local'.

Scheme defaults to 'http' if none is provided

`job` is the job label to be attached to all pushed metrics

`registry` is an instance of CollectorRegistry

`grouping_key` please see the pushgateway documentation for details.

Defaults to None

`timeout` is how long push will attempt to connect before giving up.

Defaults to None

This overwrites all metrics with the same job and grouping_key.

This uses the PUT HTTP method.'''

_use_gateway('PUT', gateway, job, registry, grouping_key, timeout)

def pushadd_to_gateway(gateway, job, registry, grouping_key=None, timeout=None):

'''PushAdd metrics to the given pushgateway.

`gateway` the url for your push gateway. Either of the form

'http://pushgateway.local', or 'pushgateway.local'.

Scheme defaults to 'http' if none is provided

`job` is the job label to be attached to all pushed metrics

`registry` is an instance of CollectorRegistry

`grouping_key` please see the pushgateway documentation for details.

Defaults to None

`timeout` is how long push will attempt to connect before giving up.

Defaults to None

This replaces metrics with the same name, job and grouping_key.

This uses the POST HTTP method.'''

_use_gateway('POST', gateway, job, registry, grouping_key, timeout)

def delete_from_gateway(gateway, job, grouping_key=None, timeout=None):

'''Delete metrics from the given pushgateway.

`gateway` the url for your push gateway. Either of the form

'http://pushgateway.local', or 'pushgateway.local'.

Scheme defaults to 'http' if none is provided

`job` is the job label to be attached to all pushed metrics

`grouping_key` please see the pushgateway documentation for details.

Defaults to None

`timeout` is how long delete will attempt to connect before giving up.

Defaults to None

This deletes metrics with the given job and grouping_key.

This uses the DELETE HTTP method.'''

_use_gateway('DELETE', gateway, job, None, grouping_key, timeout)

def _use_gateway(method, gateway, job, registry, grouping_key, timeout):

if not (gateway.startswith('http://') or gateway.startswith('https://')):

gateway = 'http://{0}'.format(gateway)

url = '{0}/metrics/job/{1}'.format(gateway, quote_plus(job))

data = b''

if method != 'DELETE':

data = generate_latest(registry)

if grouping_key is None:

grouping_key = {}

url = url + ''.join(['/{0}/{1}'.format(quote_plus(str(k)), quote_plus(str(v)))

for k, v in sorted(grouping_key.items())])

request = Request(url, data=data)

request.add_header('Content-Type', CONTENT_TYPE_LATEST)

request.get_method = lambda: method

resp = build_opener(HTTPHandler).open(request, timeout=timeout)

if resp.code >= 400:

raise IOError("error talking to pushgateway: {0} {1}".format(

resp.code, resp.msg))

def instance_ip_grouping_key():

'''Grouping key with instance set to the IP Address of this host.'''

with closing(socket.socket(socket.AF_INET, socket.SOCK_DGRAM)) as s:

s.connect(('localhost', 0))

return {'instance': s.getsockname()[0]}