Creating prototype of SliTopologyUtils, a topology utility for simple topology manipulation.

Change-Id: I3c83eeb9c44f04a8d7b0e45429594de96f162c3d
Signed-off-by: Decheng Zhang <decheng.zhang@huawei.com>

1 files changed, 108 insertions, 0 deletions

diff --git a/core/sliPluginUtils/provider/src/main/java/org/onap/ccsdk/sli/core/slipluginutils/SliTopologyUtils.java b/core/sliPluginUtils/provider/src/main/java/org/onap/ccsdk/sli/core/slipluginutils/SliTopologyUtils.java
new file mode 100644
index 000000000..9cfc305c9
--- /dev/null
+++ b/core/sliPluginUtils/provider/src/main/java/org/onap/ccsdk/sli/core/slipluginutils/SliTopologyUtils.java
@@ -0,0 +1,108 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP : CCSDK
+ * ================================================================================
+ * 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.ccsdk.sli.core.slipluginutils;
+
+import org.apache.commons.lang3.StringUtils;
+import org.onap.ccsdk.sli.core.sli.SvcLogicContext;
+import org.onap.ccsdk.sli.core.sli.SvcLogicException;
+import org.onap.ccsdk.sli.core.sli.SvcLogicJavaPlugin;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Map;
+
+public class SliTopologyUtils implements SvcLogicJavaPlugin {
+
+    private static final Logger LOG = LoggerFactory.getLogger(SliTopologyUtils.class);
+    public static final String SUCCESS_CONSTANT = "success";
+    public static final String FAILURE_CONSTANT = "failure";
+    public static final String NOT_FOUND_CONSTANT = "not-found";
+
+
+    public SliTopologyUtils(){};
+    /**
+     * Provides simple path computation functionality to Directed Graphs.
+     * <p>
+     * @param parameters HashMap<String,String> of parameters passed by the DG to this function
+     * <table border="1">
+     * 	<thead><th>parameter</th><th>Mandatory/Optional</th><th>description</th></thead>
+     * 	<tbody>
+     * 		<tr><td>pnfs-pfx</td><td>Mandatory</td><td>Prefix in context memory to get the pnf attributes from.</td></tr>
+     * 		<tr><td>links-pfx</td><td>Mandatory</td><td>Prefix in context memory to get the link attributes from.</td></tr>
+     * 		<tr><td>src-node</td><td>Mandatory</td><td>Source pnf name.</td></tr>
+     * 		<tr><td>dst-node</td><td>Mandatory</td><td>Destination pnf name.</td></tr>
+     * 		<tr><td>response-pfx</td><td>Mandatory</td><td>Prefix in context memory to populate the resulting attributes in.</td></tr>
+     * 		<tr><td>output-end-to-end-path</td><td>Optional</td><td>true or false to output end to end full path. If not included, only output cross domain path</td></tr>
+     * 	</tbody>
+     * </table>
+     * @param ctx Reference to context memory
+     * @throws SvcLogicException
+     */
+    public static String computePath(Map<String, String> parameters, SvcLogicContext ctx ) throws SvcLogicException {
+        try{
+            LOG.debug( "ENTERING Execute Node \"computePath\"" );
+
+            // Validate, Log, & read parameters
+            checkParameters(parameters, new String[]{ "pnfs-pfx", "links-pfx",
+                    "src-node", "dst-node", "response-pfx"}, LOG);
+
+            return SUCCESS_CONSTANT;
+
+
+        } catch( Exception e ) {
+            throw new SvcLogicException( "An error occurred in the computePath Execute node", e );
+        } finally {
+            LOG.debug( "EXITING Execute Node \"computePath\"" );
+        }
+    }
+
+    /**
+     * Throws an exception and writes an error to the log file if a required
+     * parameters is not found in the parametersMap.
+     * <p>
+     * Use at the beginning of functions that can be called by Directed Graphs
+     * and can take parameters to verify that all parameters have been provided
+     * by the Directed Graph.
+     * @param parametersMap parameters Map passed to this node
+     * @param requiredParams Array of parameters required by the calling function
+     * @param log Reference to Logger to log to
+     * @throws SvcLogicException if a String in the requiredParams array is
+     * not a key in parametersMap.
+     * @since 1.0
+     */
+    public static final void checkParameters(Map<String, String> parametersMap, String[] requiredParams, Logger log) throws SvcLogicException {
+        if( requiredParams == null || requiredParams.length < 1){
+            log.debug("required parameters was empty, exiting early.");
+            return;
+        }
+        if (parametersMap == null || parametersMap.keySet().isEmpty()){
+            String errorMessage = "This method requires the parameters [" +   StringUtils.join(requiredParams,",") + "], but no parameters were passed in.";
+            log.error(errorMessage);
+            throw new SvcLogicException(errorMessage);
+        }
+
+        for (String param : requiredParams) {
+            if (!parametersMap.containsKey(param)) {
+                String errorMessage = "Required parameter \"" + param + "\" was not found in parameter list.";
+                log.error(errorMessage);
+                log.error("Total list of required parameters is [" + StringUtils.join(requiredParams, ",") + "].");
+                throw new SvcLogicException(errorMessage);
+            }
+        }
+    }
+}
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