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from __future__ import unicode_literals
import base64
from contextlib import closing
import os
import socket
import sys
import threading
from wsgiref.simple_server import make_server, WSGIServer, WSGIRequestHandler
from .openmetrics import exposition as openmetrics
from .registry import REGISTRY
from .utils import floatToGoString
try:
from BaseHTTPServer import BaseHTTPRequestHandler, HTTPServer
from SocketServer import ThreadingMixIn
from urllib2 import build_opener, Request, HTTPHandler
from urllib import quote_plus
from urlparse import parse_qs, urlparse
except ImportError:
# Python 3
from http.server import BaseHTTPRequestHandler, HTTPServer
from socketserver import ThreadingMixIn
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"""
PYTHON26_OR_OLDER = sys.version_info < (2, 7)
PYTHON376_OR_NEWER = sys.version_info > (3, 7, 5)
def _bake_output(registry, accept_header, params):
"""Bake output for metrics output."""
encoder, content_type = choose_encoder(accept_header)
if 'name[]' in params:
registry = registry.restricted_registry(params['name[]'])
output = encoder(registry)
return str('200 OK'), (str('Content-Type'), content_type), output
def make_wsgi_app(registry=REGISTRY):
"""Create a WSGI app which serves the metrics from a registry."""
def prometheus_app(environ, start_response):
# Prepare parameters
accept_header = environ.get('HTTP_ACCEPT')
params = parse_qs(environ.get('QUERY_STRING', ''))
# Bake output
status, header, output = _bake_output(registry, accept_header, params)
# Return output
start_response(status, [header])
return [output]
return prometheus_app
class _SilentHandler(WSGIRequestHandler):
"""WSGI handler that does not log requests."""
def log_message(self, format, *args):
"""Log nothing."""
class ThreadingWSGIServer(ThreadingMixIn, WSGIServer):
"""Thread per request HTTP server."""
# Make worker threads "fire and forget". Beginning with Python 3.7 this
# prevents a memory leak because ``ThreadingMixIn`` starts to gather all
# non-daemon threads in a list in order to join on them at server close.
daemon_threads = True
def start_wsgi_server(port, addr='', registry=REGISTRY):
"""Starts a WSGI server for prometheus metrics as a daemon thread."""
app = make_wsgi_app(registry)
httpd = make_server(addr, port, app, ThreadingWSGIServer, handler_class=_SilentHandler)
t = threading.Thread(target=httpd.serve_forever)
t.daemon = True
t.start()
start_http_server = start_wsgi_server
def generate_latest(registry=REGISTRY):
"""Returns the metrics from the registry in latest text format as a string."""
def sample_line(line):
if line.labels:
labelstr = '{{{0}}}'.format(','.join(
['{0}="{1}"'.format(
k, v.replace('\\', r'\\').replace('\n', r'\n').replace('"', r'\"'))
for k, v in sorted(line.labels.items())]))
else:
labelstr = ''
timestamp = ''
if line.timestamp is not None:
# Convert to milliseconds.
timestamp = ' {0:d}'.format(int(float(line.timestamp) * 1000))
return '{0}{1} {2}{3}\n'.format(
line.name, labelstr, floatToGoString(line.value), timestamp)
output = []
for metric in registry.collect():
try:
mname = metric.name
mtype = metric.type
# Munging from OpenMetrics into Prometheus format.
if mtype == 'counter':
mname = mname + '_total'
elif mtype == 'info':
mname = mname + '_info'
mtype = 'gauge'
elif mtype == 'stateset':
mtype = 'gauge'
elif mtype == 'gaugehistogram':
# A gauge histogram is really a gauge,
# but this captures the structure better.
mtype = 'histogram'
elif mtype == 'unknown':
mtype = 'untyped'
output.append('# HELP {0} {1}\n'.format(
mname, metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))
output.append('# TYPE {0} {1}\n'.format(mname, mtype))
om_samples = {}
for s in metric.samples:
for suffix in ['_created', '_gsum', '_gcount']:
if s.name == metric.name + suffix:
# OpenMetrics specific sample, put in a gauge at the end.
om_samples.setdefault(suffix, []).append(sample_line(s))
break
else:
output.append(sample_line(s))
except Exception as exception:
exception.args = (exception.args or ('',)) + (metric,)
raise
for suffix, lines in sorted(om_samples.items()):
output.append('# HELP {0}{1} {2}\n'.format(metric.name, suffix,
metric.documentation.replace('\\', r'\\').replace('\n', r'\n')))
output.append('# TYPE {0}{1} gauge\n'.format(metric.name, suffix))
output.extend(lines)
return ''.join(output).encode('utf-8')
def choose_encoder(accept_header):
accept_header = accept_header or ''
for accepted in accept_header.split(','):
if accepted.split(';')[0].strip() == 'application/openmetrics-text':
return (openmetrics.generate_latest,
openmetrics.CONTENT_TYPE_LATEST)
return generate_latest, CONTENT_TYPE_LATEST
class MetricsHandler(BaseHTTPRequestHandler):
"""HTTP handler that gives metrics from ``REGISTRY``."""
registry = REGISTRY
def do_GET(self):
# Prepare parameters
registry = self.registry
accept_header = self.headers.get('Accept')
params = parse_qs(urlparse(self.path).query)
# Bake output
status, header, output = _bake_output(registry, accept_header, params)
# Return output
self.send_response(int(status.split(' ')[0]))
self.send_header(*header)
self.end_headers()
self.wfile.write(output)
def log_message(self, format, *args):
"""Log nothing."""
@classmethod
def factory(cls, registry):
"""Returns a dynamic MetricsHandler class tied
to the passed registry.
"""
# This implementation relies on MetricsHandler.registry
# (defined above and defaulted to REGISTRY).
# As we have unicode_literals, we need to create a str()
# object for type().
cls_name = str(cls.__name__)
MyMetricsHandler = type(cls_name, (cls, object),
{"registry": registry})
return MyMetricsHandler
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 default_handler(url, method, timeout, headers, data):
"""Default handler that implements HTTP/HTTPS connections.
Used by the push_to_gateway functions. Can be re-used by other handlers."""
def handle():
request = Request(url, data=data)
request.get_method = lambda: method
for k, v in headers:
request.add_header(k, v)
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))
return handle
def basic_auth_handler(url, method, timeout, headers, data, username=None, password=None):
"""Handler that implements HTTP/HTTPS connections with Basic Auth.
Sets auth headers using supplied 'username' and 'password', if set.
Used by the push_to_gateway functions. Can be re-used by other handlers."""
def handle():
"""Handler that implements HTTP Basic Auth.
"""
if username is not None and password is not None:
auth_value = '{0}:{1}'.format(username, password).encode('utf-8')
auth_token = base64.b64encode(auth_value)
auth_header = b'Basic ' + auth_token
headers.append(['Authorization', auth_header])
default_handler(url, method, timeout, headers, data)()
return handle
def push_to_gateway(
gateway, job, registry, grouping_key=None, timeout=30,
handler=default_handler):
"""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 30s, can be set to None for no timeout.
`handler` is an optional function which can be provided to perform
requests to the 'gateway'.
Defaults to None, in which case an http or https request
will be carried out by a default handler.
If not None, the argument must be a function which accepts
the following arguments:
url, method, timeout, headers, and content
May be used to implement additional functionality not
supported by the built-in default handler (such as SSL
client certicates, and HTTP authentication mechanisms).
'url' is the URL for the request, the 'gateway' argument
described earlier will form the basis of this URL.
'method' is the HTTP method which should be used when
carrying out the request.
'timeout' requests not successfully completed after this
many seconds should be aborted. If timeout is None, then
the handler should not set a timeout.
'headers' is a list of ("header-name","header-value") tuples
which must be passed to the pushgateway in the form of HTTP
request headers.
The function should raise an exception (e.g. IOError) on
failure.
'content' is the data which should be used to form the HTTP
Message Body.
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, handler)
def pushadd_to_gateway(
gateway, job, registry, grouping_key=None, timeout=30,
handler=default_handler):
"""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 30s, can be set to None for no timeout.
`handler` is an optional function which can be provided to perform
requests to the 'gateway'.
Defaults to None, in which case an http or https request
will be carried out by a default handler.
See the 'prometheus_client.push_to_gateway' documentation
for implementation requirements.
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, handler)
def delete_from_gateway(
gateway, job, grouping_key=None, timeout=30, handler=default_handler):
"""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 30s, can be set to None for no timeout.
`handler` is an optional function which can be provided to perform
requests to the 'gateway'.
Defaults to None, in which case an http or https request
will be carried out by a default handler.
See the 'prometheus_client.push_to_gateway' documentation
for implementation requirements.
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, handler)
def _use_gateway(method, gateway, job, registry, grouping_key, timeout, handler):
gateway_url = urlparse(gateway)
# See https://bugs.python.org/issue27657 for details on urlparse in py>=3.7.6.
if not gateway_url.scheme or (
(PYTHON376_OR_NEWER or PYTHON26_OR_OLDER)
and gateway_url.scheme not in ['http', 'https']
):
gateway = 'http://{0}'.format(gateway)
url = '{0}/metrics/{1}/{2}'.format(gateway, *_escape_grouping_key("job", job))
data = b''
if method != 'DELETE':
data = generate_latest(registry)
if grouping_key is None:
grouping_key = {}
url += ''.join(
'/{0}/{1}'.format(*_escape_grouping_key(str(k), str(v)))
for k, v in sorted(grouping_key.items()))
handler(
url=url, method=method, timeout=timeout,
headers=[('Content-Type', CONTENT_TYPE_LATEST)], data=data,
)()
def _escape_grouping_key(k, v):
if v == "" :
# Per https://github.com/prometheus/pushgateway/pull/346.
return k + "@base64", "="
elif '/' in v:
# Added in Pushgateway 0.9.0.
return k + "@base64", base64.urlsafe_b64encode(v.encode("utf-8")).decode("utf-8")
else:
return k, quote_plus(v)
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]}
try:
# Python >3.5 only
from .asgi import make_asgi_app
except:
pass
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