installers/charm/kafka-k8s/reactive/kafka.py

   1 # Copyright 2021 Canonical Ltd.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License"); you may
   4 # not use this file except in compliance with the License. You may obtain
   5 # 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, WITHOUT
  11 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  12 # License for the specific language governing permissions and limitations
  13 # under the License.
  14 #
  15 # For those usages not covered by the Apache License, Version 2.0 please
  16 # contact: legal@canonical.com
  17 #
  18 # To get in touch with the maintainers, please contact:
  19 # osm-charmers@lists.launchpad.net
  20 ##
  21
  22 from charms.layer.caas_base import pod_spec_set
  23 from charms.reactive import when, when_not, hook
  24 from charms.reactive import endpoint_from_flag
  25 from charms.reactive.flags import set_flag, clear_flag
  26 from charmhelpers.core.hookenv import log, metadata, config
  27 from charms import layer
  28 from charms.osm.k8s import get_service_ip
  29
  30
  31 @hook("upgrade-charm")
  32 @when("leadership.is_leader")
  33 def upgrade():
  34     clear_flag("kafka-k8s.configured")
  35
  36
  37 @when("config.changed")
  38 @when("leadership.is_leader")
  39 def restart():
  40     clear_flag("kafka-k8s.configured")
  41
  42
  43 @when_not("zookeeper.ready")
  44 @when("leadership.is_leader")
  45 def waiting_for_zookeeper():
  46     layer.status.waiting("Waiting for Zookeeper to be ready")
  47
  48
  49 @when("zookeeper.ready")
  50 @when_not("kafka-k8s.configured")
  51 @when("leadership.is_leader")
  52 def configure():
  53     layer.status.maintenance("Configuring kafka container")
  54     try:
  55         zookeeper = endpoint_from_flag("zookeeper.ready")
  56         zk_units = zookeeper.zookeepers()
  57         zk_unit = zk_units[0]
  58         if zk_unit["port"]:
  59             cfg = config()
  60             zookeeper_uri = ""
  61             zk_pod_base_name = "zookeeper-k8s"
  62             zk_service_name = cfg.get("zookeeper-service-name")
  63             zk_num = cfg.get("zookeeper-units")
  64             if zk_num == 1:
  65                 zookeeper_uri = "{}:{}".format(zk_unit["host"], zk_unit["port"])
  66             else:
  67                 for i in range(0, zk_num):
  68                     if i:
  69                         zookeeper_uri += ","
  70                     zookeeper_uri += "{}-{}.{}:{}".format(
  71                         zk_pod_base_name, i, zk_service_name, zk_unit["port"]
  72                     )
  73             spec = make_pod_spec(zookeeper_uri)
  74             log("set pod spec:\n{}".format(spec))
  75             pod_spec_set(spec)
  76             set_flag("kafka-k8s.configured")
  77     except Exception as e:
  78         layer.status.blocked("k8s spec failed to deploy: {}".format(e))
  79
  80
  81 @when("kafka-k8s.configured")
  82 def set_kafka_active():
  83     layer.status.active("ready")
  84
  85
  86 @when("zookeeper.ready")
  87 @when_not("leadership.is_leader")
  88 def non_leaders_active():
  89     layer.status.active("ready")
  90
  91
  92 @when("kafka-k8s.configured")
  93 @when("kafka.joined", "zookeeper.ready")
  94 def serve_client():
  95     layer.status.maintenance("Sending kafka configuration")
  96     try:
  97         kafka = endpoint_from_flag("kafka.joined")
  98         zookeeper = endpoint_from_flag("zookeeper.ready")
  99         if zookeeper and kafka:
 100             service_ip = get_service_ip("kafka")
 101             if service_ip:
 102                 kafka.send_connection(
 103                     get_kafka_port(), service_ip,
 104                 )
 105                 kafka.send_zookeepers(zookeeper.zookeepers())
 106                 clear_flag("kafka.joined")
 107     except Exception as e:
 108         log("Fail sending kafka configuration: {}".format(e))
 109
 110
 111 def make_pod_spec(zookeeper_uri):
 112     """Make pod specification for Kubernetes
 113
 114     Args:
 115         zookeeper_uri (str): Zookeeper hosts appended by comma.
 116     Returns:
 117         pod_spec: Pod specification for Kubernetes
 118     """
 119
 120     with open("reactive/spec_template.yaml") as spec_file:
 121         pod_spec_template = spec_file.read()
 122
 123     md = metadata()
 124     cfg = config()
 125
 126     data = {
 127         "name": md.get("name"),
 128         "docker_image": cfg.get("image"),
 129         "port": get_kafka_port(),
 130         "zookeeper_uri": zookeeper_uri,
 131     }
 132     data.update(cfg)
 133     return pod_spec_template % data
 134
 135
 136 def get_kafka_port():
 137     """Returns Kafka port"""
 138     cfg = config()
 139     return cfg.get("advertised-port")