installers/charm/mongodb-exporter/src/pod_spec.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 from ipaddress import ip_network
  24 import logging
  25 from typing import Any, Dict, List
  26 from urllib.parse import urlparse
  27
  28 logger = logging.getLogger(__name__)
  29
  30
  31 def _validate_ip_network(network: str) -> bool:
  32     """Validate IP network.
  33
  34     Args:
  35         network (str): IP network range.
  36
  37     Returns:
  38         bool: True if valid, false otherwise.
  39     """
  40     if not network:
  41         return True
  42
  43     try:
  44         ip_network(network)
  45     except ValueError:
  46         return False
  47
  48     return True
  49
  50
  51 def _validate_data(config_data: Dict[str, Any], relation_data: Dict[str, Any]) -> bool:
  52     """Validates passed information.
  53
  54     Args:
  55         config_data (Dict[str, Any]): configuration information.
  56         relation_data (Dict[str, Any]): relation information
  57
  58     Raises:
  59         ValueError: when config and/or relation data is not valid.
  60     """
  61     config_validators = {
  62         "site_url": lambda value, _: isinstance(value, str)
  63         if value is not None
  64         else True,
  65         "cluster_issuer": lambda value, _: isinstance(value, str)
  66         if value is not None
  67         else True,
  68         "ingress_whitelist_source_range": lambda value, _: _validate_ip_network(value),
  69         "tls_secret_name": lambda value, _: isinstance(value, str)
  70         if value is not None
  71         else True,
  72     }
  73     relation_validators = {
  74         "mongodb_connection_string": lambda value, _: (
  75             isinstance(value, str) and value.startswith("mongodb://")
  76         )
  77     }
  78     problems = []
  79
  80     for key, validator in config_validators.items():
  81         valid = validator(config_data.get(key), config_data)
  82
  83         if not valid:
  84             problems.append(key)
  85
  86     for key, validator in relation_validators.items():
  87         valid = validator(relation_data.get(key), relation_data)
  88
  89         if not valid:
  90             problems.append(key)
  91
  92     if len(problems) > 0:
  93         raise ValueError("Errors found in: {}".format(", ".join(problems)))
  94
  95     return True
  96
  97
  98 def _make_pod_ports(port: int) -> List[Dict[str, Any]]:
  99     """Generate pod ports details.
 100
 101     Args:
 102         port (int): port to expose.
 103
 104     Returns:
 105         List[Dict[str, Any]]: pod port details.
 106     """
 107     return [
 108         {
 109             "name": "mongo-exporter",
 110             "containerPort": port,
 111             "protocol": "TCP",
 112         }
 113     ]
 114
 115
 116 def _make_pod_envconfig(
 117     config: Dict[str, Any], relation_state: Dict[str, Any]
 118 ) -> Dict[str, Any]:
 119     """Generate pod environment configuration.
 120
 121     Args:
 122         config (Dict[str, Any]): configuration information.
 123         relation_state (Dict[str, Any]): relation state information.
 124
 125     Returns:
 126         Dict[str, Any]: pod environment configuration.
 127     """
 128     parsed = urlparse(relation_state.get("mongodb_connection_string"))
 129
 130     envconfig = {
 131         "MONGODB_URI": f"mongodb://{parsed.netloc.split(',')[0]}{parsed.path}",
 132     }
 133
 134     if parsed.query:
 135         envconfig["MONGODB_URI"] += f"?{parsed.query}"
 136
 137     return envconfig
 138
 139
 140 def _make_pod_ingress_resources(
 141     config: Dict[str, Any], app_name: str, port: int
 142 ) -> List[Dict[str, Any]]:
 143     """Generate pod ingress resources.
 144
 145     Args:
 146         config (Dict[str, Any]): configuration information.
 147         app_name (str): application name.
 148         port (int): port to expose.
 149
 150     Returns:
 151         List[Dict[str, Any]]: pod ingress resources.
 152     """
 153     site_url = config.get("site_url")
 154
 155     if not site_url:
 156         return
 157
 158     parsed = urlparse(site_url)
 159
 160     if not parsed.scheme.startswith("http"):
 161         return
 162
 163     ingress_whitelist_source_range = config["ingress_whitelist_source_range"]
 164     cluster_issuer = config["cluster_issuer"]
 165
 166     annotations = {}
 167
 168     if ingress_whitelist_source_range:
 169         annotations[
 170             "nginx.ingress.kubernetes.io/whitelist-source-range"
 171         ] = ingress_whitelist_source_range
 172
 173     if cluster_issuer:
 174         annotations["cert-manager.io/cluster-issuer"] = cluster_issuer
 175
 176     ingress_spec_tls = None
 177
 178     if parsed.scheme == "https":
 179         ingress_spec_tls = [{"hosts": [parsed.hostname]}]
 180         tls_secret_name = config["tls_secret_name"]
 181         if tls_secret_name:
 182             ingress_spec_tls[0]["secretName"] = tls_secret_name
 183     else:
 184         annotations["nginx.ingress.kubernetes.io/ssl-redirect"] = "false"
 185
 186     ingress = {
 187         "name": "{}-ingress".format(app_name),
 188         "annotations": annotations,
 189         "spec": {
 190             "rules": [
 191                 {
 192                     "host": parsed.hostname,
 193                     "http": {
 194                         "paths": [
 195                             {
 196                                 "path": "/",
 197                                 "backend": {
 198                                     "serviceName": app_name,
 199                                     "servicePort": port,
 200                                 },
 201                             }
 202                         ]
 203                     },
 204                 }
 205             ]
 206         },
 207     }
 208     if ingress_spec_tls:
 209         ingress["spec"]["tls"] = ingress_spec_tls
 210
 211     return [ingress]
 212
 213
 214 def _make_readiness_probe(port: int) -> Dict[str, Any]:
 215     """Generate readiness probe.
 216
 217     Args:
 218         port (int): service port.
 219
 220     Returns:
 221         Dict[str, Any]: readiness probe.
 222     """
 223     return {
 224         "httpGet": {
 225             "path": "/api/health",
 226             "port": port,
 227         },
 228         "initialDelaySeconds": 10,
 229         "periodSeconds": 10,
 230         "timeoutSeconds": 5,
 231         "successThreshold": 1,
 232         "failureThreshold": 3,
 233     }
 234
 235
 236 def _make_liveness_probe(port: int) -> Dict[str, Any]:
 237     """Generate liveness probe.
 238
 239     Args:
 240         port (int): service port.
 241
 242     Returns:
 243         Dict[str, Any]: liveness probe.
 244     """
 245     return {
 246         "httpGet": {
 247             "path": "/api/health",
 248             "port": port,
 249         },
 250         "initialDelaySeconds": 60,
 251         "timeoutSeconds": 30,
 252         "failureThreshold": 10,
 253     }
 254
 255
 256 def make_pod_spec(
 257     image_info: Dict[str, str],
 258     config: Dict[str, Any],
 259     relation_state: Dict[str, Any],
 260     app_name: str = "mongodb-exporter",
 261     port: int = 9216,
 262 ) -> Dict[str, Any]:
 263     """Generate the pod spec information.
 264
 265     Args:
 266         image_info (Dict[str, str]): Object provided by
 267                                      OCIImageResource("image").fetch().
 268         config (Dict[str, Any]): Configuration information.
 269         relation_state (Dict[str, Any]): Relation state information.
 270         app_name (str, optional): Application name. Defaults to "ro".
 271         port (int, optional): Port for the container. Defaults to 9090.
 272
 273     Returns:
 274         Dict[str, Any]: Pod spec dictionary for the charm.
 275     """
 276     if not image_info:
 277         return None
 278
 279     _validate_data(config, relation_state)
 280
 281     ports = _make_pod_ports(port)
 282     env_config = _make_pod_envconfig(config, relation_state)
 283     readiness_probe = _make_readiness_probe(port)
 284     liveness_probe = _make_liveness_probe(port)
 285     ingress_resources = _make_pod_ingress_resources(config, app_name, port)
 286
 287     return {
 288         "version": 3,
 289         "containers": [
 290             {
 291                 "name": app_name,
 292                 "imageDetails": image_info,
 293                 "imagePullPolicy": "Always",
 294                 "ports": ports,
 295                 "envConfig": env_config,
 296                 "kubernetes": {
 297                     "readinessProbe": readiness_probe,
 298                     "livenessProbe": liveness_probe,
 299                 },
 300             }
 301         ],
 302         "kubernetesResources": {
 303             "ingressResources": ingress_resources or [],
 304         },
 305     }