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>"
"created": 1593445184,
"version": "1.0" # to allow future version updates
},
- 'scrape_configs': [{'static_configs': [{'targets': ['mon:8000']}], 'job_name': 'mon_exporter'}],
+ '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():
+class Prometheus:
"""
Implements a class to update Prometheus
"""
self.worker_id = worker_id
self.db = db
self.loop = loop
- self.logger = logger or logging.get_legger("lcm.prometheus")
+ self.logger = logger or logging.getLogger("lcm.prometheus")
self.server = config["uri"]
self.path = config["path"]
if not self.path.endswith("/"):
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=True)
+ 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=None, remove_jobs=None):
+ 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(4):
result = True
if retry: # first time do not wait
await asyncio.sleep(self.PROMETHEUS_LOCKED_TIME / 2, loop=self.loop)
+
# lock database
now = time()
if not self.db.set_one(
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_list = pull_list = None
+ push_dict = pull_dict = None
if add_jobs or remove_jobs:
- update_dict = {"_admin.locked_at": 0,
- "_admin.locked_by": None,
- "_admin.modified_at": now}
+ log_text_list = []
if add_jobs:
- push_list = {"scrape_configs.static_configs": add_jobs}
- prometheus_data["scrape_configs"]["static_configs"] += 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:
- pass # TODO
- if not self.send_data(prometheus_data):
- push_list = pull_list = None
- result = False
+ 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(". ".join(log_text_list))
+
+ if not await self.send_data(prometheus_data):
+ 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, pull_list=pull_list, push_list=push_list, fail_on_empty=False):
+ 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.dump(new_config, 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:
+ async with session.post(self.server + "-/reload") as resp:
if resp.status > 204:
- raise LcmException(resp.text)
+ raise LcmException(await resp.text())
await asyncio.sleep(5, loop=self.loop)
- async with session.get(self.server + "/api/v1/status/config") as resp:
+ # 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(resp.text)
- current_config = resp.json()
+ 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 prometheus configuration {}".format(e))
+ self.logger.error("Error updating prometheus configuration url={}: {}".format(self.server, e))
return False
finally:
if restore_backup:
- os.rename(self.cfg_file_backup, self.cfg_file)
+ try:
+ os.rename(self.cfg_file_backup, self.cfg_file)
+ except Exception as e:
+ self.logger.critical("Exception while rolling back: {}".format(e))
- @staticmethod
- def _check_configuration_equal(current_config, new_config):
- # TODO compare and return True if equal
- return True
+ 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"]]
+ return current_jobs == expected_jobs
+ except Exception as e:
+ self.logger.error("Invalid obtained prometheus status. Error: '{}'. Obtained data: '{}'".format(
+ e, current_config))
+ # if format is not understood, cannot be compared, assume it is ok
+ return True