1 files changed, 135 insertions, 0 deletions
diff --git a/openecomp-be/lib/openecomp-common-lib/src/main/java/org/openecomp/sdc/common/CommonConfigurationManager.java b/openecomp-be/lib/openecomp-common-lib/src/main/java/org/openecomp/sdc/common/CommonConfigurationManager.java
new file mode 100644
index 0000000000..46747fb881
--- /dev/null
+++ b/openecomp-be/lib/openecomp-common-lib/src/main/java/org/openecomp/sdc/common/CommonConfigurationManager.java
@@ -0,0 +1,135 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * SDC
+ * ================================================================================
+ * Copyright (C) 2017, 2021 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.openecomp.sdc.common;
+
+import org.onap.sdc.tosca.services.YamlUtil;
+import org.openecomp.sdc.logging.api.Logger;
+import org.openecomp.sdc.logging.api.LoggerFactory;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.function.BiConsumer;
+
+/**
+ * This is a common class that can access the config file given in input to the JVM with the parameter
+ * -Dconfiguration.yaml=file.yaml.
+ */
+public class CommonConfigurationManager {
+    public static final String JVM_PARAM_CONFIGURATION_FILE = "configuration.yaml";
+    private static final Logger LOGGER = LoggerFactory.getLogger(CommonConfigurationManager.class);
+    private static CommonConfigurationManager singletonInstance;
+    private Map<String, LinkedHashMap<String, Object>> configuration;
+    private String configFilename;
+    private String yamlSection;
+
+    protected CommonConfigurationManager() {
+        initConfiguration();
+    }
+
+    protected CommonConfigurationManager(String yamlSection) {
+        this();
+        this.yamlSection = yamlSection;
+    }
+
+    public static synchronized CommonConfigurationManager getInstance() {
+        if (singletonInstance == null) {
+            singletonInstance = new CommonConfigurationManager();
+        }
+        return singletonInstance;
+    }
+
+    private void initConfiguration() {
+        YamlUtil yamlUtil = new YamlUtil();
+        readConfigurationFromStream(yamlUtil, (filename, stream) -> {
+            this.configFilename = filename;
+            if (stream == null) {
+                LOGGER.warn("Configuration not found: " + filename + ". Using defaults");
+                return;
+            }
+            Map<String, LinkedHashMap<String, Object>> configurationMap = yamlUtil.yamlToMap(stream);
+            if (configurationMap == null) {
+                LOGGER.warn("Configuration cannot be parsed: " + filename + ". Using defaults");
+                return;
+            } else {
+                this.configuration = configurationMap;
+            }
+        });
+    }
+
+    private void readConfigurationFromStream(YamlUtil yamlUtil, BiConsumer<String, InputStream> reader) {
+        String configurationYamlFile = System.getProperty(JVM_PARAM_CONFIGURATION_FILE);
+        try {
+            if (configurationYamlFile == null) {
+                try (InputStream inputStream = yamlUtil.loadYamlFileIs("/" + JVM_PARAM_CONFIGURATION_FILE)) {
+                    reader.accept(JVM_PARAM_CONFIGURATION_FILE, inputStream);
+                }
+            } else {
+                try (InputStream inputStream = new FileInputStream(configurationYamlFile)) {
+                    reader.accept(configurationYamlFile, inputStream);
+                }
+            }
+        } catch (IOException e) {
+            LOGGER.error("Failed to read configuration " + configurationYamlFile, e);
+            throw new RuntimeException("Failed to read configuration " + configurationYamlFile, e);
+        }
+    }
+
+    /**
+     * This method can be used to access any yaml section configuration.
+     *
+     * @param yamlSection  The yaml section that must be accessed
+     * @param name         The configuration name inside that yaml section
+     * @param defaultValue A default value
+     * @param <T>          The type of value to be returned
+     * @return The value found or the default value if not found
+     */
+    public <T> T getConfigValue(String yamlSection, String name, T defaultValue) {
+        Map<String, Object> section = this.configuration.get(yamlSection);
+        if (section == null) {
+            LOGGER.error("Section " + yamlSection + " is missing in configuration file '" + configFilename +
+                    "'. Using defaults");
+            return defaultValue;
+        }
+        Object value = section.get(name);
+        try {
+            return value == null ? defaultValue : (T) value;
+        } catch (ClassCastException e) {
+            LOGGER.warn(
+                    String.format("Failed to read configuration property '%s' as requested type. Using default '%s'",
+                            name, defaultValue), e);
+            return defaultValue;
+        }
+    }
+
+    /**
+     * This method can be used to access a specific configuration parameter in the configuration in the
+     * yamlSection predefined in the constructor.
+     *
+     * @param name         The name of the config
+     * @param defaultValue A default value
+     * @param <T>          The type of value to be returned
+     * @return The value found or the default value if not found
+     */
+    public <T> T getConfigValue(String name, T defaultValue) {
+        return this.getConfigValue(yamlSection, name, defaultValue);
+    }
+}