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Diffstat (limited to 'synapse/metrics/_legacy_exposition.py')
| -rw-r--r-- | synapse/metrics/_legacy_exposition.py | 288 |
1 files changed, 0 insertions, 288 deletions
diff --git a/synapse/metrics/_legacy_exposition.py b/synapse/metrics/_legacy_exposition.py deleted file mode 100644 index 1459f9d224..0000000000 --- a/synapse/metrics/_legacy_exposition.py +++ /dev/null @@ -1,288 +0,0 @@ -# Copyright 2015-2019 Prometheus Python Client Developers -# Copyright 2019 Matrix.org Foundation C.I.C. -# -# Licensed under the Apache License, Version 2.0 (the "License"); -# you may not use this file except in compliance with the License. -# You may obtain a copy of the License at -# -# http://www.apache.org/licenses/LICENSE-2.0 -# -# Unless required by applicable law or agreed to in writing, software -# distributed under the License is distributed on an "AS IS" BASIS, -# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -# See the License for the specific language governing permissions and -# limitations under the License. - -""" -This code is based off `prometheus_client/exposition.py` from version 0.7.1. - -Due to the renaming of metrics in prometheus_client 0.4.0, this customised -vendoring of the code will emit both the old versions that Synapse dashboards -expect, and the newer "best practice" version of the up-to-date official client. -""" -import logging -import math -import threading -from http.server import BaseHTTPRequestHandler, HTTPServer -from socketserver import ThreadingMixIn -from typing import Any, Dict, List, Type, Union -from urllib.parse import parse_qs, urlparse - -from prometheus_client import REGISTRY, CollectorRegistry -from prometheus_client.core import Sample - -from twisted.web.resource import Resource -from twisted.web.server import Request - -logger = logging.getLogger(__name__) -CONTENT_TYPE_LATEST = "text/plain; version=0.0.4; charset=utf-8" - - -def floatToGoString(d: Union[int, float]) -> str: - d = float(d) - if d == math.inf: - return "+Inf" - elif d == -math.inf: - return "-Inf" - elif math.isnan(d): - return "NaN" - else: - s = repr(d) - dot = s.find(".") - # Go switches to exponents sooner than Python. - # We only need to care about positive values for le/quantile. - if d > 0 and dot > 6: - mantissa = f"{s[0]}.{s[1:dot]}{s[dot + 1 :]}".rstrip("0.") - return f"{mantissa}e+0{dot - 1}" - return s - - -def sample_line(line: Sample, name: str) -> str: - if line.labels: - labelstr = "{{{0}}}".format( - ",".join( - [ - '{}="{}"'.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 = f" {int(float(line.timestamp) * 1000):d}" - return "{}{} {}{}\n".format(name, labelstr, floatToGoString(line.value), timestamp) - - -# Mapping from new metric names to legacy metric names. -# We translate these back to their old names when exposing them through our -# legacy vendored exporter. -# Only this legacy exposition module applies these name changes. -LEGACY_METRIC_NAMES = { - "synapse_util_caches_cache_hits": "synapse_util_caches_cache:hits", - "synapse_util_caches_cache_size": "synapse_util_caches_cache:size", - "synapse_util_caches_cache_evicted_size": "synapse_util_caches_cache:evicted_size", - "synapse_util_caches_cache": "synapse_util_caches_cache:total", - "synapse_util_caches_response_cache_size": "synapse_util_caches_response_cache:size", - "synapse_util_caches_response_cache_hits": "synapse_util_caches_response_cache:hits", - "synapse_util_caches_response_cache_evicted_size": "synapse_util_caches_response_cache:evicted_size", - "synapse_util_caches_response_cache": "synapse_util_caches_response_cache:total", - "synapse_federation_client_sent_pdu_destinations": "synapse_federation_client_sent_pdu_destinations:total", - "synapse_federation_client_sent_pdu_destinations_count": "synapse_federation_client_sent_pdu_destinations:count", - "synapse_admin_mau_current": "synapse_admin_mau:current", - "synapse_admin_mau_max": "synapse_admin_mau:max", - "synapse_admin_mau_registered_reserved_users": "synapse_admin_mau:registered_reserved_users", -} - - -def generate_latest(registry: CollectorRegistry, emit_help: bool = False) -> bytes: - """ - Generate metrics in legacy format. Modern metrics are generated directly - by prometheus-client. - """ - - output = [] - - for metric in registry.collect(): - if not metric.samples: - # No samples, don't bother. - continue - - # Translate to legacy metric name if it has one. - mname = LEGACY_METRIC_NAMES.get(metric.name, metric.name) - mnewname = metric.name - mtype = metric.type - - # OpenMetrics -> Prometheus - if mtype == "counter": - mnewname = mnewname + "_total" - elif mtype == "info": - mtype = "gauge" - mnewname = mnewname + "_info" - elif mtype == "stateset": - mtype = "gauge" - elif mtype == "gaugehistogram": - mtype = "histogram" - elif mtype == "unknown": - mtype = "untyped" - - # Output in the old format for compatibility. - if emit_help: - output.append( - "# HELP {} {}\n".format( - mname, - metric.documentation.replace("\\", r"\\").replace("\n", r"\n"), - ) - ) - output.append(f"# TYPE {mname} {mtype}\n") - - om_samples: Dict[str, List[str]] = {} - for s in metric.samples: - for suffix in ["_created", "_gsum", "_gcount"]: - if s.name == mname + suffix: - # OpenMetrics specific sample, put in a gauge at the end. - # (these come from gaugehistograms which don't get renamed, - # so no need to faff with mnewname) - om_samples.setdefault(suffix, []).append(sample_line(s, s.name)) - break - else: - newname = s.name.replace(mnewname, mname) - if ":" in newname and newname.endswith("_total"): - newname = newname[: -len("_total")] - output.append(sample_line(s, newname)) - - for suffix, lines in sorted(om_samples.items()): - if emit_help: - output.append( - "# HELP {}{} {}\n".format( - mname, - suffix, - metric.documentation.replace("\\", r"\\").replace("\n", r"\n"), - ) - ) - output.append(f"# TYPE {mname}{suffix} gauge\n") - output.extend(lines) - - # Get rid of the weird colon things while we're at it - if mtype == "counter": - mnewname = mnewname.replace(":total", "") - mnewname = mnewname.replace(":", "_") - - if mname == mnewname: - continue - - # Also output in the new format, if it's different. - if emit_help: - output.append( - "# HELP {} {}\n".format( - mnewname, - metric.documentation.replace("\\", r"\\").replace("\n", r"\n"), - ) - ) - output.append(f"# TYPE {mnewname} {mtype}\n") - - for s in metric.samples: - # Get rid of the OpenMetrics specific samples (we should already have - # dealt with them above anyway.) - for suffix in ["_created", "_gsum", "_gcount"]: - if s.name == mname + suffix: - break - else: - sample_name = LEGACY_METRIC_NAMES.get(s.name, s.name) - output.append( - sample_line(s, sample_name.replace(":total", "").replace(":", "_")) - ) - - return "".join(output).encode("utf-8") - - -class MetricsHandler(BaseHTTPRequestHandler): - """HTTP handler that gives metrics from ``REGISTRY``.""" - - registry = REGISTRY - - def do_GET(self) -> None: - registry = self.registry - params = parse_qs(urlparse(self.path).query) - - if "help" in params: - emit_help = True - else: - emit_help = False - - try: - output = generate_latest(registry, emit_help=emit_help) - except Exception: - self.send_error(500, "error generating metric output") - raise - try: - self.send_response(200) - self.send_header("Content-Type", CONTENT_TYPE_LATEST) - self.send_header("Content-Length", str(len(output))) - self.end_headers() - self.wfile.write(output) - except BrokenPipeError as e: - logger.warning( - "BrokenPipeError when serving metrics (%s). Did Prometheus restart?", e - ) - - def log_message(self, format: str, *args: Any) -> None: - """Log nothing.""" - - @classmethod - def factory(cls, registry: CollectorRegistry) -> Type: - """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 - - -class _ThreadingSimpleServer(ThreadingMixIn, HTTPServer): - """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. - # Enabling daemon threads virtually makes ``_ThreadingSimpleServer`` the - # same as Python 3.7's ``ThreadingHTTPServer``. - daemon_threads = True - - -def start_http_server( - port: int, addr: str = "", registry: CollectorRegistry = REGISTRY -) -> None: - """Starts an HTTP server for prometheus metrics as a daemon thread""" - CustomMetricsHandler = MetricsHandler.factory(registry) - httpd = _ThreadingSimpleServer((addr, port), CustomMetricsHandler) - t = threading.Thread(target=httpd.serve_forever) - t.daemon = True - t.start() - - -class MetricsResource(Resource): - """ - Twisted ``Resource`` that serves prometheus metrics. - """ - - isLeaf = True - - def __init__(self, registry: CollectorRegistry = REGISTRY): - self.registry = registry - - def render_GET(self, request: Request) -> bytes: - request.setHeader(b"Content-Type", CONTENT_TYPE_LATEST.encode("ascii")) - response = generate_latest(self.registry) - request.setHeader(b"Content-Length", str(len(response))) - return response |