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