installers/charm/ng-ui/src/charm.py

   1 #!/usr/bin/env python3
   2 #   Copyright 2020 Canonical Ltd.
   3 #
   4 #   Licensed under the Apache License, Version 2.0 (the "License");
   5 #   you may not use this file except in compliance with the License.
   6 #   You may obtain 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,
  12 #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 #   See the License for the specific language governing permissions and
  14 #   limitations under the License.
  15
  16 import sys
  17 import logging
  18
  19 sys.path.append("lib")
  20
  21 from ops.charm import CharmBase
  22 from ops.framework import StoredState, Object
  23 from ops.main import main
  24 from ops.model import (
  25     ActiveStatus,
  26     MaintenanceStatus,
  27 )
  28
  29 from glob import glob
  30 from pathlib import Path
  31 from string import Template
  32
  33 logger = logging.getLogger(__name__)
  34
  35
  36 class NGUICharm(CharmBase):
  37     state = StoredState()
  38
  39     def __init__(self, framework, key):
  40         super().__init__(framework, key)
  41         self.state.set_default(spec=None)
  42
  43         # Observe Charm related events
  44         self.framework.observe(self.on.config_changed, self.on_config_changed)
  45         self.framework.observe(self.on.start, self.on_start)
  46         self.framework.observe(self.on.upgrade_charm, self.on_upgrade_charm)
  47         # self.framework.observe(
  48         #     self.on.nbi_relation_joined, self.on_nbi_relation_joined
  49         # )
  50
  51     def _apply_spec(self):
  52         # Only apply the spec if this unit is a leader.
  53         if not self.framework.model.unit.is_leader():
  54             return
  55         new_spec = self.make_pod_spec()
  56         if new_spec == self.state.spec:
  57             return
  58         self.framework.model.pod.set_spec(new_spec)
  59         self.state.spec = new_spec
  60
  61     def make_pod_spec(self):
  62         config = self.framework.model.config
  63
  64         ports = [
  65             {"name": "port", "containerPort": config["port"], "protocol": "TCP",},
  66         ]
  67
  68         kubernetes = {
  69             "readinessProbe": {
  70                 "tcpSocket": {"port": config["port"]},
  71                 "timeoutSeconds": 5,
  72                 "periodSeconds": 5,
  73                 "initialDelaySeconds": 10,
  74             },
  75             "livenessProbe": {
  76                 "tcpSocket": {"port": config["port"]},
  77                 "timeoutSeconds": 5,
  78                 "initialDelaySeconds": 45,
  79             },
  80         }
  81         config_spec = {
  82             "port": config["port"],
  83             "server_name": config["server_name"],
  84             "client_max_body_size": config["client_max_body_size"],
  85             "nbi_hostname": config["nbi_hostname"],
  86             "nbi_port": config["nbi_port"],
  87         }
  88
  89         files = [
  90             {
  91                 "name": "configuration",
  92                 "mountPath": "/etc/nginx/sites-available/",
  93                 "files": {
  94                     Path(filename)
  95                     .name: Template(Path(filename).read_text())
  96                     .substitute(config_spec)
  97                     for filename in glob("files/*")
  98                 },
  99             },
 100         ]
 101         logger.debug(files)
 102         spec = {
 103             "version": 2,
 104             "containers": [
 105                 {
 106                     "name": self.framework.model.app.name,
 107                     "image": "{}".format(config["image"]),
 108                     "ports": ports,
 109                     "kubernetes": kubernetes,
 110                     "files": files,
 111                 }
 112             ],
 113         }
 114
 115         return spec
 116
 117     def on_config_changed(self, event):
 118         """Handle changes in configuration"""
 119         unit = self.model.unit
 120         unit.status = MaintenanceStatus("Applying new pod spec")
 121         self._apply_spec()
 122         unit.status = ActiveStatus("Ready")
 123
 124     def on_start(self, event):
 125         """Called when the charm is being installed"""
 126         unit = self.model.unit
 127         unit.status = MaintenanceStatus("Applying pod spec")
 128         self._apply_spec()
 129         unit.status = ActiveStatus("Ready")
 130
 131     def on_upgrade_charm(self, event):
 132         """Upgrade the charm."""
 133         unit = self.model.unit
 134         unit.status = MaintenanceStatus("Upgrading charm")
 135         self.on_start(event)
 136
 137     # def on_nbi_relation_joined(self, event):
 138     #     unit = self.model.unit
 139     #     if not unit.is_leader():
 140     #         return
 141     #     config = self.framework.model.config
 142     #     unit = MaintenanceStatus("Sending connection data")
 143
 144     #     unit = ActiveStatus("Ready")
 145
 146
 147 if __name__ == "__main__":
 148     main(NGUICharm)