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 (
  94             self.kafka_client.is_missing_data_in_unit()
  95             and self.kafka_client.is_missing_data_in_app()
  96         ):
  97             missing_relations.append("kafka")
  98         if not config.mongodb_uri and self.mongodb_client.is_missing_data_in_unit():
  99             missing_relations.append("mongodb")
 100
 101         if missing_relations:
 102             raise RelationsMissing(missing_relations)
 103
 104     def build_pod_spec(self, image_info):
 105         # Validate config
 106         config = ConfigModel(**dict(self.config))
 107
 108         if config.mongodb_uri and not self.mongodb_client.is_missing_data_in_unit():
 109             raise Exception("Mongodb data cannot be provided via config and relation")
 110
 111         # Check relations
 112         self._check_missing_dependencies(config)
 113
 114         # Create Builder for the PodSpec
 115         pod_spec_builder = PodSpecV3Builder(
 116             enable_security_context=config.security_context
 117         )
 118
 119         # Add secrets to the pod
 120         mongodb_secret_name = f"{self.app.name}-mongodb-secret"
 121         pod_spec_builder.add_secret(
 122             mongodb_secret_name,
 123             {
 124                 "uri": config.mongodb_uri or self.mongodb_client.connection_string,
 125                 "commonkey": config.database_commonkey,
 126             },
 127         )
 128
 129         # Build Container
 130         container_builder = ContainerV3Builder(
 131             self.app.name,
 132             image_info,
 133             config.image_pull_policy,
 134             run_as_non_root=config.security_context,
 135         )
 136         container_builder.add_port(name=self.app.name, port=PORT)
 137         container_builder.add_envs(
 138             {
 139                 # General configuration
 140                 "ALLOW_ANONYMOUS_LOGIN": "yes",
 141                 "OSMPLA_GLOBAL_LOG_LEVEL": config.log_level,
 142                 # Kafka configuration
 143                 "OSMPLA_MESSAGE_DRIVER": "kafka",
 144                 "OSMPLA_MESSAGE_HOST": self.kafka_client.host,
 145                 "OSMPLA_MESSAGE_PORT": self.kafka_client.port,
 146                 # Database configuration
 147                 "OSMPLA_DATABASE_DRIVER": "mongo",
 148             }
 149         )
 150
 151         container_builder.add_secret_envs(
 152             secret_name=mongodb_secret_name,
 153             envs={
 154                 "OSMPLA_DATABASE_URI": "uri",
 155                 "OSMPLA_DATABASE_COMMONKEY": "commonkey",
 156             },
 157         )
 158
 159         container = container_builder.build()
 160
 161         # Add Pod restart policy
 162         restart_policy = PodRestartPolicy()
 163         restart_policy.add_secrets(secret_names=(mongodb_secret_name))
 164         pod_spec_builder.set_restart_policy(restart_policy)
 165
 166         # Add container to pod spec
 167         pod_spec_builder.add_container(container)
 168
 169         return pod_spec_builder.build()
 170
 171
 172 if __name__ == "__main__":
 173     main(PlaCharm)