--- /dev/null
+# -*- coding: utf-8 -*-
+
+##
+# Copyright 2020 Telefonica S.A.
+#
+# 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.
+##
+
+import asyncio
+from time import time
+import logging
+import aiohttp
+import yaml
+import os
+from osm_lcm.lcm_utils import LcmException
+from osm_common.dbbase import DbException
+from jinja2 import Template, TemplateError, TemplateNotFound, TemplateSyntaxError
+
+__author__ = "Alfonso Tierno <alfonso.tiernosepulveda@telefonica.com>"
+
+initial_prometheus_data = {
+ "_id": "prometheus",
+ "_admin": {
+ "locked_at": 0,
+ "locked_by": None,
+ "modified": 1593445184, # 2020-06-29
+ "created": 1593445184,
+ "version": "1.0" # to allow future version updates
+ },
+ 'scrape_configs': { # Dictionary at database. Converted to list before sending to prometheus
+ 'mon_exporter': {'static_configs': [{'targets': ['mon:8000']}], 'job_name': 'mon_exporter'},
+ },
+ 'global': {'evaluation_interval': '15s', 'scrape_interval': '15s'},
+ 'rule_files': None,
+ 'alerting': {'alertmanagers': [{'static_configs': [{'targets': None}]}]}
+}
+
+
+class Prometheus:
+ """
+ Implements a class to update Prometheus
+ """
+
+ PROMETHEUS_LOCKED_TIME = 120
+
+ def __init__(self, config, worker_id, db, loop, logger=None):
+ self.worker_id = worker_id
+ self.db = db
+ self.loop = loop
+ self.logger = logger or logging.getLogger("lcm.prometheus")
+ self.server = config["uri"]
+ self.path = config["path"]
+ if not self.path.endswith("/"):
+ self.path += "/"
+ self.cfg_file = self.path + "prometheus.yml"
+ self.cfg_file_backup = self.path + "prometheus.yml-backup"
+
+ @staticmethod
+ def parse_job(job_data: str, variables: dict) -> dict:
+ try:
+ template = Template(job_data)
+ job_parsed = template.render(variables or {})
+ return yaml.safe_load(job_parsed)
+ except (TemplateError, TemplateNotFound, TemplateSyntaxError) as e:
+ # TODO yaml exceptions
+ raise LcmException("Error parsing Jinja2 to prometheus job. job_data={}, variables={}. Error={}".format(
+ job_data, variables, e))
+
+ async def start(self):
+ for retry in range(4):
+ try:
+ # self.logger("Starting prometheus ")
+ # read from database
+ prometheus_data = self.db.get_one("admin", {"_id": "prometheus"}, fail_on_empty=False)
+ if not prometheus_data:
+ self.logger.info("Init db.admin.prometheus content")
+ self.db.create("admin", initial_prometheus_data)
+ # send database config file to prometheus. Ignore loading errors, as prometheus may be starting
+ # but at least an initial configuration file is set
+ await self.update()
+ return
+ except DbException as e:
+ if retry == 3:
+ raise LcmException("Max retries trying to init prometheus configuration: {}".format(e))
+ await asyncio.sleep(5, loop=self.loop)
+
+ async def update(self, add_jobs: dict = None, remove_jobs: list = None) -> bool:
+ """
+
+ :param add_jobs: dictionary with {job_id_1: job_content, job_id_2: job_content}
+ :param remove_jobs: list with jobs to remove [job_id_1, job_id_2]
+ :return: result. If false prometheus denies this configuration. Exception on error
+ """
+ for retry in range(20):
+ result = True
+ if retry: # first time do not wait
+ await asyncio.sleep(4 + retry, loop=self.loop)
+
+ # lock database
+ now = time()
+ if not self.db.set_one(
+ "admin",
+ q_filter={"_id": "prometheus", "_admin.locked_at.lt": now - self.PROMETHEUS_LOCKED_TIME},
+ update_dict={"_admin.locked_at": now, "_admin.locked_by": self.worker_id},
+ fail_on_empty=False):
+ continue
+ # read database
+ prometheus_data = self.db.get_one("admin", {"_id": "prometheus"})
+ update_dict = {"_admin.locked_at": 0,
+ "_admin.locked_by": None}
+
+ # Make changes from prometheus_incremental
+ push_dict = pull_dict = None
+ if add_jobs or remove_jobs:
+ log_text_list = []
+ if add_jobs:
+ log_text_list.append("adding jobs: {}".format(list(add_jobs.keys())))
+ prometheus_data["scrape_configs"].update(add_jobs)
+ push_dict = {"scrape_configs." + job_id: job_data for job_id, job_data in add_jobs.items()}
+ elif remove_jobs:
+ log_text_list.append("removing jobs: {}".format(list(remove_jobs)))
+ for job_id in remove_jobs:
+ prometheus_data["scrape_configs"].pop(job_id, None)
+ pull_dict = {"scrape_configs." + job_id: None for job_id in remove_jobs}
+ self.logger.debug("Updating. " + ". ".join(log_text_list))
+
+ if not await self.send_data(prometheus_data):
+ self.logger.error("Cannot update add_jobs: {}. remove_jobs: {}".format(add_jobs, remove_jobs))
+ push_dict = pull_dict = None
+ result = False
+
+ # unblock database
+ if push_dict:
+ update_dict.update(push_dict)
+ if push_dict or pull_dict:
+ update_dict["_admin.modified_at"] = now
+ if not self.db.set_one(
+ "admin", {"_id": "prometheus", "_admin.locked_at": now, "_admin.locked_by": self.worker_id},
+ update_dict=update_dict, unset=pull_dict, fail_on_empty=False):
+ continue
+ return result
+ raise LcmException("Cannot update prometheus database. Reached max retries")
+
+ async def send_data(self, new_config):
+ restore_backup = False
+ del new_config["_id"]
+ del new_config["_admin"]
+ new_scrape_configs = []
+
+ # generate a list with the values of scrape_configs
+ for scrape_config in new_config["scrape_configs"].values():
+ scrape_config = scrape_config.copy()
+ # remove nsr_id metadata from scrape_configs
+ scrape_config.pop("nsr_id", None)
+ new_scrape_configs.append(scrape_config)
+ new_config["scrape_configs"] = new_scrape_configs
+
+ try:
+ if os.path.exists(self.cfg_file):
+ os.rename(self.cfg_file, self.cfg_file_backup)
+ restore_backup = True
+ with open(self.cfg_file, "w+") as f:
+ yaml.safe_dump(new_config, f, indent=4, default_flow_style=False)
+ # self.logger.debug("new configuration: {}".format(yaml.safe_dump(new_config, indent=4,
+ # default_flow_style=False)))
+ async with aiohttp.ClientSession() as session:
+ async with session.post(self.server + "-/reload") as resp:
+ if resp.status > 204:
+ raise LcmException(await resp.text())
+ await asyncio.sleep(5, loop=self.loop)
+ # If prometheus does not admit this configuration, remains with the old one
+ # Then, to check if the configuration has been accepted, get the configuration from prometheus
+ # and compares with the inserted one
+ async with session.get(self.server + "api/v1/status/config") as resp:
+ if resp.status > 204:
+ raise LcmException(await resp.text())
+ current_config = await resp.json()
+ if not self._check_configuration_equal(current_config, new_config):
+ return False
+ else:
+ restore_backup = False
+ return True
+ except Exception as e:
+ self.logger.error("Error updating configuration url={}: {}".format(self.server, e))
+ return False
+ finally:
+ if restore_backup:
+ try:
+ os.rename(self.cfg_file_backup, self.cfg_file)
+ except Exception as e:
+ self.logger.critical("Exception while rolling back: {}".format(e))
+
+ def _check_configuration_equal(self, current_config, expected_config):
+ try:
+ # self.logger.debug("Comparing current_config='{}' with expected_config='{}'".format(current_config,
+ # expected_config))
+ current_config_yaml = yaml.safe_load(current_config['data']['yaml'])
+ current_jobs = [j["job_name"] for j in current_config_yaml["scrape_configs"]]
+ expected_jobs = [j["job_name"] for j in expected_config["scrape_configs"]]
+ if current_jobs == expected_jobs:
+ return True
+ else:
+ self.logger.error("Not all jobs have been loaded. Target jobs: {} Loaded jobs: {}".format(
+ expected_jobs, current_jobs))
+ return False
+ except Exception as e:
+ self.logger.error("Invalid obtained status from server. Error: '{}'. Obtained data: '{}'".format(
+ e, current_config))
+ # if format is not understood, cannot be compared, assume it is ok
+ return True
projects / osm / LCM.git / blobdiff