installers/charm/pla/src/charm.py

   1 #!/usr/bin/env python3
   2 # Copyright 2021 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 # pylint: disable=E0213
  24
  25
  26 import logging
  27 from typing import NoReturn, Optional
  28
  29 from ops.main import main
  30 from opslib.osm.charm import CharmedOsmBase, RelationsMissing
  31 from opslib.osm.interfaces.kafka import KafkaClient
  32 from opslib.osm.interfaces.mongo import MongoClient
  33 from opslib.osm.pod import (
  34     ContainerV3Builder,
  35     PodRestartPolicy,
  36     PodSpecV3Builder,
  37 )
  38 from opslib.osm.validator import ModelValidator, validator
  39
  40
  41 logger = logging.getLogger(__name__)
  42
  43 PORT = 9999
  44
  45
  46 class ConfigModel(ModelValidator):
  47     database_commonkey: str
  48     mongodb_uri: Optional[str]
  49     log_level: str
  50     image_pull_policy: str
  51     security_context: bool
  52
  53     @validator("log_level")
  54     def validate_log_level(cls, v):
  55         if v not in {"INFO", "DEBUG"}:
  56             raise ValueError("value must be INFO or DEBUG")
  57         return v
  58
  59     @validator("mongodb_uri")
  60     def validate_mongodb_uri(cls, v):
  61         if v and not v.startswith("mongodb://"):
  62             raise ValueError("mongodb_uri is not properly formed")
  63         return v
  64
  65     @validator("image_pull_policy")
  66     def validate_image_pull_policy(cls, v):
  67         values = {
  68             "always": "Always",
  69             "ifnotpresent": "IfNotPresent",
  70             "never": "Never",
  71         }
  72         v = v.lower()
  73         if v not in values.keys():
  74             raise ValueError("value must be always, ifnotpresent or never")
  75         return values[v]
  76
  77
  78 class PlaCharm(CharmedOsmBase):
  79     def __init__(self, *args) -> NoReturn:
  80         super().__init__(*args, oci_image="image")
  81
  82         self.kafka_client = KafkaClient(self, "kafka")
  83         self.framework.observe(self.on["kafka"].relation_changed, self.configure_pod)
  84         self.framework.observe(self.on["kafka"].relation_broken, self.configure_pod)
  85
  86         self.mongodb_client = MongoClient(self, "mongodb")
  87         self.framework.observe(self.on["mongodb"].relation_changed, self.configure_pod)
  88         self.framework.observe(self.on["mongodb"].relation_broken, self.configure_pod)
  89
  90     def _check_missing_dependencies(self, config: ConfigModel):
  91         missing_relations = []
  92
  93         if self.kafka_client.is_missing_data_in_unit():
  94             missing_relations.append("kafka")
  95         if not config.mongodb_uri and self.mongodb_client.is_missing_data_in_unit():
  96             missing_relations.append("mongodb")
  97
  98         if missing_relations:
  99             raise RelationsMissing(missing_relations)
 100
 101     def build_pod_spec(self, image_info):
 102         # Validate config
 103         config = ConfigModel(**dict(self.config))
 104
 105         if config.mongodb_uri and not self.mongodb_client.is_missing_data_in_unit():
 106             raise Exception("Mongodb data cannot be provided via config and relation")
 107
 108         # Check relations
 109         self._check_missing_dependencies(config)
 110
 111         # Create Builder for the PodSpec
 112         pod_spec_builder = PodSpecV3Builder(
 113             enable_security_context=config.security_context
 114         )
 115
 116         # Add secrets to the pod
 117         mongodb_secret_name = f"{self.app.name}-mongodb-secret"
 118         pod_spec_builder.add_secret(
 119             mongodb_secret_name,
 120             {
 121                 "uri": config.mongodb_uri or self.mongodb_client.connection_string,
 122                 "commonkey": config.database_commonkey,
 123             },
 124         )
 125
 126         # Build Container
 127         container_builder = ContainerV3Builder(
 128             self.app.name,
 129             image_info,
 130             config.image_pull_policy,
 131             run_as_non_root=config.security_context,
 132         )
 133         container_builder.add_port(name=self.app.name, port=PORT)
 134         container_builder.add_envs(
 135             {
 136                 # General configuration
 137                 "ALLOW_ANONYMOUS_LOGIN": "yes",
 138                 "OSMPLA_GLOBAL_LOG_LEVEL": config.log_level,
 139                 # Kafka configuration
 140                 "OSMPLA_MESSAGE_DRIVER": "kafka",
 141                 "OSMPLA_MESSAGE_HOST": self.kafka_client.host,
 142                 "OSMPLA_MESSAGE_PORT": self.kafka_client.port,
 143                 # Database configuration
 144                 "OSMPLA_DATABASE_DRIVER": "mongo",
 145             }
 146         )
 147
 148         container_builder.add_secret_envs(
 149             secret_name=mongodb_secret_name,
 150             envs={
 151                 "OSMPLA_DATABASE_URI": "uri",
 152                 "OSMPLA_DATABASE_COMMONKEY": "commonkey",
 153             },
 154         )
 155
 156         container = container_builder.build()
 157
 158         # Add Pod restart policy
 159         restart_policy = PodRestartPolicy()
 160         restart_policy.add_secrets(secret_names=(mongodb_secret_name))
 161         pod_spec_builder.set_restart_policy(restart_policy)
 162
 163         # Add container to pod spec
 164         pod_spec_builder.add_container(container)
 165
 166         return pod_spec_builder.build()
 167
 168
 169 if __name__ == "__main__":
 170     main(PlaCharm)