1 files changed, 77 insertions, 0 deletions
diff --git a/src/main/java/org/onap/dcae/controller/EnvPropertiesReader.java b/src/main/java/org/onap/dcae/controller/EnvPropertiesReader.java
new file mode 100644
index 00000000..23bcbda8
--- /dev/null
+++ b/src/main/java/org/onap/dcae/controller/EnvPropertiesReader.java
@@ -0,0 +1,77 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * org.onap.dcaegen2.collectors.ves
+ * ================================================================================
+ * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * Copyright (C) 2018 Nokia. 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=========================================================
+ */
+package org.onap.dcae.controller;
+
+import static io.vavr.API.List;
+import static io.vavr.API.Try;
+import static org.onap.dcae.commonFunction.event.publishing.VavrUtils.f;
+
+import io.vavr.collection.Map;
+import io.vavr.control.Option;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+final class EnvPropertiesReader {
+
+    private final static Logger log = LoggerFactory.getLogger(EnvPropertiesReader.class);
+
+    static Option<EnvProps> readEnvProps(Map<String, String> environmentVariables) {
+        log.info("Loading necessary environment variables for dynamic configuration update");
+        int consulPort = getConsulPort(environmentVariables);
+        Option<String> consulHost = getConsulHost(environmentVariables);
+        Option<String> cbsServiceName = getCBSName(environmentVariables);
+        Option<String> vesCollectorAppName = getAppName(environmentVariables);
+        return Option.sequence(List(consulHost, cbsServiceName, vesCollectorAppName))
+            .map(e -> new EnvProps(e.get(0), consulPort, e.get(1), e.get(2)))
+            .onEmpty(() -> log.warn("Some required environment variables are missing"))
+            .peek(props -> log.info(f("Discovered following environment variables: '%s'", props)));
+    }
+
+    private static Option<String> getAppName(Map<String, String> environmentVariables) {
+        return environmentVariables.get("HOSTNAME")
+            .orElse(environmentVariables.get("SERVICE_NAME"))
+            .onEmpty(() -> log.warn("App service name (as registered in CBS) (env var: 'HOSTNAME' / 'SERVICE_NAME') "
+                + "is missing error environment variables."));
+    }
+
+    private static Option<String> getCBSName(Map<String, String> environmentVariables) {
+        return environmentVariables.get("CONFIG_BINDING_SERVICE")
+            .onEmpty(() -> log.warn("Name of CBS Service (as registered in Consul) (env var: 'CONFIG_BINDING_SERVICE') "
+                + "is missing from environment variables."));
+    }
+
+    private static Integer getConsulPort(Map<String, String> environmentVariables) {
+        return environmentVariables.get("CONSUL_PORT")
+            .flatMap(str -> Try(() -> Integer.valueOf(str))
+                .onFailure(exc -> log.warn("Consul port is not an integer value", exc))
+                .toOption())
+            .onEmpty(() -> log.warn("Consul port (env var: 'CONSUL_PORT') is missing from environment variables. "
+                + "Using default value of 8500"))
+            .getOrElse(8500);
+    }
+
+    private static Option<String> getConsulHost(Map<String, String> environmentVariables) {
+        return environmentVariables.get("CONSUL_HOST")
+            .onEmpty(() -> log.warn("Consul host (env var: 'CONSUL_HOST') (without port) "
+                + "is missing from environment variables."));
+    }
+
+}