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