1 files changed, 128 insertions, 0 deletions
diff --git a/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/supplier/ConfigBindingServiceJsonSupplier.java b/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/supplier/ConfigBindingServiceJsonSupplier.java
new file mode 100644
index 0000000..b882bb0
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+++ b/dcae-analytics/dcae-analytics-model/src/main/java/org/onap/dcae/analytics/model/util/supplier/ConfigBindingServiceJsonSupplier.java
@@ -0,0 +1,128 @@
+/*
+ * ================================================================================
+ * Copyright (c) 2018 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=========================================================
+ *
+ */
+
+package org.onap.dcae.analytics.model.util.supplier;
+
+
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+import org.onap.dcae.analytics.model.configbindingservice.ConfigBindingServiceConstants;
+import org.onap.dcae.analytics.model.configbindingservice.ConsulConfigBindingServiceQueryResponse;
+import org.onap.dcae.analytics.model.util.function.StringToURLFunction;
+import org.onap.dcae.analytics.model.util.function.URLToHttpGetFunction;
+import org.onap.dcae.analytics.model.util.json.AnalyticsModelJsonConversion;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A Function which fetches ApplicationProperties configuration from
+ * Config Binding Service when deployed via docker, typically during application startup time.
+ *
+ * @author Rajiv Singla
+ */
+public class ConfigBindingServiceJsonSupplier implements Supplier<Optional<String>> {
+
+    private static final Logger logger = LoggerFactory.getLogger(ConfigBindingServiceJsonSupplier.class);
+
+    private final Function<String, Optional<String>> fetchUrlContentFunction;
+
+    public ConfigBindingServiceJsonSupplier(final Function<String, Optional<String>> fetchUrlContentFunction) {
+        this.fetchUrlContentFunction = fetchUrlContentFunction;
+    }
+
+    public ConfigBindingServiceJsonSupplier() {
+        fetchUrlContentFunction = (String s) -> new StringToURLFunction().apply(s).flatMap(new URLToHttpGetFunction());
+    }
+
+    @Override
+    public Optional<String> get() {
+
+        logger.info("Consul Host Environment Variable: {}",
+                ConfigBindingServiceConstants.CONSUL_HOST_ENV_VARIABLE_VALUE);
+        logger.info("Config Binding Service Environment Variable: {}",
+                ConfigBindingServiceConstants.CONFIG_BINDING_SERVICE_ENV_VARIABLE_VALUE);
+        logger.info("Service Name Environment Variable: {}",
+                ConfigBindingServiceConstants.SERVICE_NAME_ENV_VARIABLE_VALUE);
+
+        if (ConfigBindingServiceConstants.CONSUL_HOST_ENV_VARIABLE_VALUE == null ||
+                ConfigBindingServiceConstants.CONFIG_BINDING_SERVICE_ENV_VARIABLE_VALUE == null ||
+                ConfigBindingServiceConstants.SERVICE_NAME_ENV_VARIABLE_VALUE == null) {
+            logger.error("Environment variables required to query Config Binding Service are not present");
+            return Optional.empty();
+        }
+
+        return Optional.of(ConfigBindingServiceConstants.CONSUL_QUERY_URL_STRING)
+                // Step 1: Query CONSUL to get the IP/PORT of CONFIG BINDING SERVICE
+                .flatMap(fetchUrlContentFunction)
+                // Step 2: Fetch the generated configurations from CONFIG BINDING SERVICE
+                .flatMap(ConfigBindingServiceJsonSupplier::parseConsulConfigBindingServiceQueryResponseJson)
+                // Step 3: create url from service address and service port
+                .flatMap(ConfigBindingServiceJsonSupplier::createConfigServiceURL)
+                // Step 4: Fetch final config binding service generated application configuration json string
+                .flatMap(fetchUrlContentFunction);
+    }
+
+    /**
+     * Creates URL using config binding service ip address and port
+     *
+     * @param consulConfigBindingServiceQueryResponse consul config binding service query response containing config
+     * binding service address and service port
+     *
+     * @return config service url to fetch service configuration
+     */
+    private static Optional<String> createConfigServiceURL(final ConsulConfigBindingServiceQueryResponse
+                                                                   consulConfigBindingServiceQueryResponse) {
+        final String configBindingServiceAddress = consulConfigBindingServiceQueryResponse.getServiceAddress();
+        final Integer configServicePort = consulConfigBindingServiceQueryResponse.getServicePort();
+
+        if (configBindingServiceAddress == null && configServicePort == null) {
+            logger.error("Config Binding Service Address & Port are not present.");
+            return Optional.empty();
+        }
+
+        return Optional.of(String.format(ConfigBindingServiceConstants.CONFIG_SERVICE_QUERY_URL_STRING,
+                configBindingServiceAddress, configServicePort,
+                ConfigBindingServiceConstants.SERVICE_NAME_ENV_VARIABLE_VALUE));
+
+    }
+
+    private static Optional<ConsulConfigBindingServiceQueryResponse>
+    parseConsulConfigBindingServiceQueryResponseJson(final String configBindingServiceQueryResponseJson) {
+        // parse json
+        final Optional<List<ConsulConfigBindingServiceQueryResponse>> configBindingServiceQueryResponseOptional =
+                AnalyticsModelJsonConversion.CONFIG_BINDING_SERVICE_LIST_JSON_FUNCTION
+                        .apply(configBindingServiceQueryResponseJson);
+
+        // check parsing is successful and at least 1 config binding query response is present
+        if (!configBindingServiceQueryResponseOptional.isPresent() ||
+                configBindingServiceQueryResponseOptional.get().isEmpty()) {
+            logger.error("No Consul config binding service information found in JSON: {} ",
+                    configBindingServiceQueryResponseJson);
+            return Optional.empty();
+        }
+
+        // return first consul query response
+        return Optional.of(configBindingServiceQueryResponseOptional.get().get(0));
+    }
+
+
+}