installers/charm/pol/src/pod_spec.py

   1 #!/usr/bin/env python3
   2 # Copyright 2020 Canonical Ltd.
   3 #
   4 # Licensed under the Apache License, Version 2.0 (the "License"); you may
   5 # not use this file except in compliance with the License. You may obtain
   6 # a copy of the License at
   7 #
   8 #         http://www.apache.org/licenses/LICENSE-2.0
   9 #
  10 # Unless required by applicable law or agreed to in writing, software
  11 # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  12 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  13 # License for the specific language governing permissions and limitations
  14 # under the License.
  15 #
  16 # For those usages not covered by the Apache License, Version 2.0 please
  17 # contact: legal@canonical.com
  18 #
  19 # To get in touch with the maintainers, please contact:
  20 # osm-charmers@lists.launchpad.net
  21 ##
  22
  23 import logging
  24 from typing import Any, Dict, List, NoReturn
  25
  26 logger = logging.getLogger(__name__)
  27
  28
  29 def _validate_data(
  30     config_data: Dict[str, Any], relation_data: Dict[str, Any]
  31 ) -> NoReturn:
  32     """Validate input data.
  33
  34     Args:
  35         config_data (Dict[str, Any]): configuration data.
  36         relation_data (Dict[str, Any]): relation data.
  37     """
  38     config_validators = {
  39         "log_level": lambda value, _: (
  40             isinstance(value, str) and value in ("INFO", "DEBUG")
  41         ),
  42     }
  43     relation_validators = {
  44         "message_host": lambda value, _: isinstance(value, str) and len(value) > 0,
  45         "message_port": lambda value, _: isinstance(value, int) and value > 0,
  46         "database_uri": lambda value, _: (
  47             isinstance(value, str) and value.startswith("mongodb://")
  48         ),
  49     }
  50     problems = []
  51
  52     for key, validator in config_validators.items():
  53         valid = validator(config_data.get(key), config_data)
  54
  55         if not valid:
  56             problems.append(key)
  57
  58     for key, validator in relation_validators.items():
  59         valid = validator(relation_data.get(key), relation_data)
  60
  61         if not valid:
  62             problems.append(key)
  63
  64     if len(problems) > 0:
  65         raise ValueError("Errors found in: {}".format(", ".join(problems)))
  66
  67
  68 def _make_pod_ports(port: int) -> List[Dict[str, Any]]:
  69     """Generate pod ports details.
  70
  71     Args:
  72         port (int): port to expose.
  73
  74     Returns:
  75         List[Dict[str, Any]]: pod port details.
  76     """
  77     return [{"name": "pol", "containerPort": port, "protocol": "TCP"}]
  78
  79
  80 def _make_pod_envconfig(
  81     config: Dict[str, Any], relation_state: Dict[str, Any]
  82 ) -> Dict[str, Any]:
  83     """Generate pod environment configuration.
  84
  85     Args:
  86         config (Dict[str, Any]): configuration information.
  87         relation_state (Dict[str, Any]): relation state information.
  88
  89     Returns:
  90         Dict[str, Any]: pod environment configuration.
  91     """
  92     envconfig = {
  93         # General configuration
  94         "ALLOW_ANONYMOUS_LOGIN": "yes",
  95         "OSMPOL_GLOBAL_LOGLEVEL": config["log_level"],
  96         # Kafka configuration
  97         "OSMPOL_MESSAGE_HOST": relation_state["message_host"],
  98         "OSMPOL_MESSAGE_DRIVER": "kafka",
  99         "OSMPOL_MESSAGE_PORT": relation_state["message_port"],
 100         # Database configuration
 101         "OSMPOL_DATABASE_DRIVER": "mongo",
 102         "OSMPOL_DATABASE_URI": relation_state["database_uri"],
 103     }
 104
 105     return envconfig
 106
 107
 108 def _make_startup_probe() -> Dict[str, Any]:
 109     """Generate startup probe.
 110
 111     Returns:
 112         Dict[str, Any]: startup probe.
 113     """
 114     return {
 115         "exec": {"command": ["/usr/bin/pgrep", "python3"]},
 116         "initialDelaySeconds": 60,
 117         "timeoutSeconds": 5,
 118     }
 119
 120
 121 def _make_readiness_probe() -> Dict[str, Any]:
 122     """Generate readiness probe.
 123
 124     Returns:
 125         Dict[str, Any]: readiness probe.
 126     """
 127     return {
 128         "exec": {
 129             "command": ["sh", "-c", "osm-pol-healthcheck || exit 1"],
 130         },
 131         "periodSeconds": 10,
 132         "timeoutSeconds": 5,
 133         "successThreshold": 1,
 134         "failureThreshold": 3,
 135     }
 136
 137
 138 def _make_liveness_probe() -> Dict[str, Any]:
 139     """Generate liveness probe.
 140
 141     Returns:
 142         Dict[str, Any]: liveness probe.
 143     """
 144     return {
 145         "exec": {
 146             "command": ["sh", "-c", "osm-pol-healthcheck || exit 1"],
 147         },
 148         "initialDelaySeconds": 45,
 149         "periodSeconds": 10,
 150         "timeoutSeconds": 5,
 151         "successThreshold": 1,
 152         "failureThreshold": 3,
 153     }
 154
 155
 156 def make_pod_spec(
 157     image_info: Dict[str, str],
 158     config: Dict[str, Any],
 159     relation_state: Dict[str, Any],
 160     app_name: str = "pol",
 161     port: int = 80,
 162 ) -> Dict[str, Any]:
 163     """Generate the pod spec information.
 164
 165     Args:
 166         image_info (Dict[str, str]): Object provided by
 167                                      OCIImageResource("image").fetch().
 168         config (Dict[str, Any]): Configuration information.
 169         relation_state (Dict[str, Any]): Relation state information.
 170         app_name (str, optional): Application name. Defaults to "pol".
 171         port (int, optional): Port for the container. Defaults to 80.
 172
 173     Returns:
 174         Dict[str, Any]: Pod spec dictionary for the charm.
 175     """
 176     if not image_info:
 177         return None
 178
 179     _validate_data(config, relation_state)
 180
 181     ports = _make_pod_ports(port)
 182     env_config = _make_pod_envconfig(config, relation_state)
 183
 184     return {
 185         "version": 3,
 186         "containers": [
 187             {
 188                 "name": app_name,
 189                 "imageDetails": image_info,
 190                 "imagePullPolicy": "Always",
 191                 "ports": ports,
 192                 "envConfig": env_config,
 193             }
 194         ],
 195         "kubernetesResources": {
 196             "ingressResources": [],
 197         },
 198     }