# 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': [{'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.get_legger("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"
-
- async def start(self):
- for retry in range(4):
- try:
- # read from database
- prometheus_data = self.db.get_one("admin", {"_id": "prometheus"}, fail_on_empty=True)
- 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()
- 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):
- 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(
- "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"})
-
- # Make changes from prometheus_incremental
- push_list = pull_list = None
- if add_jobs or remove_jobs:
- update_dict = {"_admin.locked_at": 0,
- "_admin.locked_by": None,
- "_admin.modified_at": now}
- if add_jobs:
- push_list = {"scrape_configs.static_configs": add_jobs}
- prometheus_data["scrape_configs"]["static_configs"] += add_jobs
- elif remove_jobs:
- pass # TODO
- if not self.send_data(prometheus_data):
- push_list = pull_list = None
- result = False
-
- # unblock database
- 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):
- continue
- return result
- raise LcmException("Cannot update prometheus database. Reached max retries")
-
- async def send_data(self, new_config):
- restore_backup = False
- 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)
- async with aiohttp.ClientSession() as session:
- async with session.post(self.server + "/-/reload") as resp:
- if resp.status > 204:
- raise LcmException(resp.text)
- await asyncio.sleep(5, loop=self.loop)
- async with session.get(self.server + "/api/v1/status/config") as resp:
- if resp.status > 204:
- raise LcmException(resp.text)
- current_config = 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))
- return False
- finally:
- if restore_backup:
- os.rename(self.cfg_file_backup, self.cfg_file)
- @staticmethod
- def _check_configuration_equal(current_config, new_config):
- # TODO compare and return True if equal
- return True
+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
+ )
+ )