1 files changed, 73 insertions, 0 deletions
diff --git a/policyhandler/discovery.py b/policyhandler/discovery.py
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+++ b/policyhandler/discovery.py
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+"""client to talk to consul at the standard port 8500"""
+
+# org.onap.dcae
+# ================================================================================
+# Copyright (c) 2017 AT&T Intellectual Property. All rights reserved.
+# ================================================================================
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============LICENSE_END=========================================================
+#
+# ECOMP is a trademark and service mark of AT&T Intellectual Property.
+
+import logging
+import json
+import base64
+import requests
+
+class DiscoveryClient(object):
+    """talking to consul at http://consul:8500
+
+    relies on proper --add-host "consul:<consul-agent ip>" in
+    docker run command that runs along the consul-agent:
+
+    docker run --name ${APPNAME} -d
+        -e HOSTNAME
+        --add-host "consul:<consul-agent ip>"
+        -v ${BASEDIR}/logs:${TARGETDIR}/logs
+        -v ${BASEDIR}/etc:${TARGETDIR}/etc
+        -p <outport>:<innerport>
+        ${APPNAME}:latest
+    """
+    CONSUL_SERVICE_MASK = "http://consul:8500/v1/catalog/service/{0}"
+    CONSUL_KV_MASK = "http://consul:8500/v1/kv/{0}"
+    SERVICE_MASK = "http://{0}:{1}"
+    _logger = logging.getLogger("policy_handler.discovery")
+
+
+    @staticmethod
+    def get_service_url(service_name):
+        """find the service record in consul"""
+        service_path = DiscoveryClient.CONSUL_SERVICE_MASK.format(service_name)
+        DiscoveryClient._logger.info("discover %s", service_path)
+        response = requests.get(service_path)
+        response.raise_for_status()
+        service = response.json()[0]
+        return DiscoveryClient.SERVICE_MASK.format( \
+                service["ServiceAddress"], service["ServicePort"])
+
+    @staticmethod
+    def get_value(key):
+        """get the value for the key from consul-kv"""
+        response = requests.get(DiscoveryClient.CONSUL_KV_MASK.format(key))
+        response.raise_for_status()
+        data = response.json()[0]
+        value = base64.b64decode(data["Value"]).decode("utf-8")
+        DiscoveryClient._logger.info("consul-kv key=%s data=%s value(%s)", \
+            key, json.dumps(data), value)
+        return json.loads(value)
+
+    @staticmethod
+    def put_kv(key, value):
+        """put the value under the key in consul-kv"""
+        response = requests.put(DiscoveryClient.CONSUL_KV_MASK.format(key), data=value)
+        response.raise_for_status()