# 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 osm_lcm.data_utils.database.database import Database
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, loop, logger=None):
- self.worker_id = worker_id
- self.db = Database().instance.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
- )
+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
)
- # if format is not understood, cannot be compared, assume it is ok
- return True
+ )
projects / osm / LCM.git / blobdiff