installers/charm/pol-k8s/reactive/pol_k8s.py

   1 # Copyright 2020 Canonical Ltd.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 #     Unless required by applicable law or agreed to in writing, software
  10 #     distributed under the License is distributed on an "AS IS" BASIS,
  11 #     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 #     See the License for the specific language governing permissions and
  13 #     limitations under the License.
  14 from charms.reactive import endpoint_from_flag
  15 from charms.layer.caas_base import pod_spec_set
  16 from charms.reactive import when, when_not, hook
  17 from charms.reactive.flags import set_flag, clear_flag
  18 from charmhelpers.core.hookenv import log, metadata, config
  19 from charms import layer
  20
  21
  22 @hook("upgrade-charm")
  23 @when("leadership.is_leader")
  24 def upgrade():
  25     clear_flag("pol-k8s.configured")
  26
  27
  28 @when("config.changed")
  29 @when("leadership.is_leader")
  30 def restart():
  31     clear_flag("pol-k8s.configured")
  32
  33
  34 @when_not("kafka.ready")
  35 @when("leadership.is_leader")
  36 @when_not("pol-k8s.configured")
  37 def waiting_for_kafka():
  38     layer.status.waiting("Waiting for kafka to be ready")
  39
  40
  41 @when_not("mongo.ready")
  42 @when("leadership.is_leader")
  43 @when_not("pol-k8s.configured")
  44 def waiting_for_mongo():
  45     layer.status.waiting("Waiting for mongo to be ready")
  46
  47
  48 @when("kafka.ready", "mongo.ready")
  49 @when_not("pol-k8s.configured")
  50 @when("leadership.is_leader")
  51 def configure():
  52     layer.status.maintenance("Configuring pol container")
  53     try:
  54         kafka = endpoint_from_flag("kafka.ready")
  55         mongo = endpoint_from_flag("mongo.ready")
  56
  57         if kafka and mongo:
  58             kafka_units = kafka.kafkas()
  59             kafka_unit = kafka_units[0]
  60
  61             mongo_uri = mongo.connection_string()
  62             log("Mongo URI: {}".format(mongo_uri))
  63
  64             if mongo_uri and kafka_unit["host"]:
  65                 spec = make_pod_spec(kafka_unit["host"], kafka_unit["port"], mongo_uri)
  66
  67                 log("set pod spec:\n{}".format(spec))
  68                 pod_spec_set(spec)
  69                 set_flag("pol-k8s.configured")
  70     except Exception as e:
  71         layer.status.blocked("k8s spec failed to deploy: {}".format(e))
  72
  73
  74 @when("kafka.ready", "mongo.ready")
  75 @when_not("leadership.is_leader")
  76 def non_leaders_active():
  77     layer.status.active("ready")
  78
  79
  80 @when("pol-k8s.configured")
  81 def set_pol_active():
  82     layer.status.active("ready")
  83
  84
  85 def make_pod_spec(kafka_host, kafka_port, mongo_uri):
  86     """Make pod specification for Kubernetes
  87
  88     Args:
  89         kafka_host (str): Kafka hostname or IP
  90         kafka_port (int): Kafka port
  91         mongo_host (str): Mongo URI
  92     Returns:
  93         pod_spec: Pod specification for Kubernetes
  94     """
  95
  96     with open("reactive/spec_template.yaml") as spec_file:
  97         pod_spec_template = spec_file.read()
  98
  99     md = metadata()
 100     cfg = config()
 101     data = {
 102         "name": md.get("name"),
 103         "kafka_host": kafka_host,
 104         "kafka_port": kafka_port,
 105         "mongo_uri": mongo_uri,
 106     }
 107     data.update(cfg)
 108     return pod_spec_template % data