installers/charm/mon-k8s/reactive/mon_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("mon-k8s.configured")
  26
  27
  28 @when("config.changed")
  29 @when("leadership.is_leader")
  30 def restart():
  31     clear_flag("mon-k8s.configured")
  32
  33
  34 @when_not("kafka.ready")
  35 @when_not("mon-k8s.configured")
  36 @when("leadership.is_leader")
  37 def waiting_for_kafka():
  38     layer.status.waiting("Waiting for kafka to be ready")
  39
  40
  41 @when_not("mongo.ready")
  42 @when_not("mon-k8s.configured")
  43 @when("leadership.is_leader")
  44 def waiting_for_mongo():
  45     layer.status.waiting("Waiting for mongo to be ready")
  46
  47
  48 @when_not("endpoint.prometheus.available")
  49 @when_not("mon-k8s.configured")
  50 @when("leadership.is_leader")
  51 def waiting_for_prometheus():
  52     layer.status.waiting("Waiting for prometheus to be ready")
  53
  54
  55 @when("kafka.ready", "mongo.ready", "endpoint.prometheus.available")
  56 @when_not("mon-k8s.configured")
  57 @when("leadership.is_leader")
  58 def configure():
  59     layer.status.maintenance("Configuring mon container")
  60     try:
  61         kafka = endpoint_from_flag("kafka.ready")
  62         mongo = endpoint_from_flag("mongo.ready")
  63         prometheus = endpoint_from_flag("endpoint.prometheus.available")
  64
  65         if kafka and mongo and prometheus:
  66             kafka_units = kafka.kafkas()
  67             kafka_unit = kafka_units[0]
  68
  69             mongo_uri = mongo.connection_string()
  70             log("Mongo URI: {}".format(mongo_uri))
  71
  72             prometheus_url = prometheus.targets()[0]["targets"][0]
  73
  74             if mongo_uri and kafka_unit["host"]:
  75
  76                 spec = make_pod_spec(
  77                     kafka_unit["host"], kafka_unit["port"], mongo_uri, prometheus_url
  78                 )
  79
  80                 log("set pod spec:\n{}".format(spec))
  81                 pod_spec_set(spec)
  82                 set_flag("mon-k8s.configured")
  83     except Exception as e:
  84         layer.status.blocked("k8s spec failed to deploy: {}".format(e))
  85
  86
  87 @when("kafka.ready", "mongo.ready", "endpoint.prometheus.available")
  88 @when_not("leadership.is_leader")
  89 def non_leaders_active():
  90     layer.status.active("ready")
  91
  92
  93 @when("mon-k8s.configured")
  94 def set_mon_active():
  95     layer.status.active("ready")
  96
  97
  98 def make_pod_spec(kafka_host, kafka_port, mongo_uri, prometheus_url):
  99     """Make pod specification for Kubernetes
 100
 101     Args:
 102         kafka_host (str): Kafka hostname or IP
 103         kafka_port (int): Kafka port
 104         mongo_uri (str): Mongo URI
 105     Returns:
 106         pod_spec: Pod specification for Kubernetes
 107     """
 108
 109     with open("reactive/spec_template.yaml") as spec_file:
 110         pod_spec_template = spec_file.read()
 111
 112     md = metadata()
 113     cfg = config()
 114
 115     data = {
 116         "name": md.get("name"),
 117         "kafka_host": kafka_host,
 118         "kafka_port": kafka_port,
 119         "mongo_uri": mongo_uri,
 120         "prometheus_url": prometheus_url,
 121     }
 122     data.update(cfg)
 123     return pod_spec_template % data