YAML clc directive spec/compilation to XACML

Created java definition of CoordinationDirective class.
Initial library supports one coordination directive FirstBlocksSecond,
prototype for this directive added as firstBlocksSecond.xml.
Functions for compiling example yaml directive are in SupportUtil.

Change-Id: If7c22402729670403510f1fa2f7f43de6a4a522c
Issue-ID: POLICY-1173
Signed-off-by: Joshua Reich <jreich@research.att.com>

2 files changed, 171 insertions, 0 deletions

diff --git a/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/CoordinationDirective.java b/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/CoordinationDirective.java
new file mode 100644
index 000000000..6ba4ca478
--- /dev/null
+++ b/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/CoordinationDirective.java
@@ -0,0 +1,67 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * guard
+ * ================================================================================
+ * Copyright (C) 2019 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.policy.coordination;
+
+import java.util.List;
+
+public class CoordinationDirective {
+
+    private List<String> controlLoop;
+    private String coordinationFunction;
+
+    public List<String> getControlLoop() {
+        return controlLoop;
+    }
+
+    /**
+     * gets the ith control loop.
+     *
+     * @param index the control loop's index
+     * @return the CoordinationDirective's string representation
+     */
+    public String getControlLoop(int index) {
+        return controlLoop.get(index);
+    }
+
+    public void setControlLoop(List<String> controlLoop) {
+        this.controlLoop = controlLoop;
+    }
+
+    public String getCoordinationFunction() {
+        return coordinationFunction;
+    }
+
+    public void setCoordinationFunction(String coordinationFunction) {
+        this.coordinationFunction = coordinationFunction;
+    }
+
+    /**
+     * toString.
+     *
+     * @return the CoordinationDirective's string representation
+     */
+    public String toString() {
+        return "CoordinationDirective[ "
+            + String.join(" / ", controlLoop)
+            + " / " + coordinationFunction + "]";
+    }
+
+}
diff --git a/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/Util.java b/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/Util.java
new file mode 100644
index 000000000..d76684093
--- /dev/null
+++ b/controlloop/common/coordination/src/main/java/org/onap/policy/coordination/Util.java
@@ -0,0 +1,104 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * controlloop
+ * ================================================================================
+ * Copyright (C) 2019 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.policy.coordination;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.UUID;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.apache.commons.io.IOUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.yaml.snakeyaml.Yaml;
+import org.yaml.snakeyaml.constructor.Constructor;
+
+
+public final class Util {
+
+    private static final Logger logger = LoggerFactory.getLogger(Util.class);
+
+    /**
+     * Load YAML coordination directive.
+     *
+     * @param directiveFilename yaml directive file to load
+     * @return the CoordinationDirective
+     */
+    public static CoordinationDirective loadCoordinationDirectiveFromFile(String directiveFilename) {
+        try (InputStream is = new FileInputStream(new File(directiveFilename))) {
+            String contents = IOUtils.toString(is, StandardCharsets.UTF_8);
+            //
+            // Read the yaml into our Java Object
+            //
+            Yaml yaml = new Yaml(new Constructor(CoordinationDirective.class));
+            Object obj = yaml.load(contents);
+
+            logger.debug(contents);
+
+            return (CoordinationDirective) obj;
+        } catch (IOException e) {
+            logger.error("Error while loading YAML coordination directive", e);
+        }
+        return null;
+    }
+
+    /**
+     * Generate Xacml rule implementing specified CoordinationDirective.
+     *
+     * @param cd the CoordinationDirective
+     * @param protoDir the directory containing Xacml implementation prototypes
+     * @return the generated Xacml policy
+     */
+    public static String generateXacmlFromCoordinationDirective(CoordinationDirective cd,
+                                                                String protoDir) {
+        /*
+         * Determine file names
+         */
+        String xacmlProtoFilename = protoDir + File.separator + cd.getCoordinationFunction() + ".xml";
+        logger.debug("xacmlProtoFilename={}", xacmlProtoFilename);
+        /*
+         * Values to be used for placeholders
+         */
+        final String uniqueId = UUID.randomUUID().toString();
+        final String cLOne = cd.getControlLoop(0);
+        final String cLTwo = cd.getControlLoop(1);
+        /*
+         * Replace prototype placeholders with appropriate values
+         */
+        String xacmlPolicy = null;
+        try (Stream<String> stream = Files.lines(Paths.get(xacmlProtoFilename))) {
+            xacmlPolicy = stream.map(s -> s.replaceAll("UNIQUE_ID", uniqueId))
+                .map(s -> s.replaceAll("CONTROL_LOOP_ONE", cLOne))
+                .map(s -> s.replaceAll("CONTROL_LOOP_TWO", cLTwo))
+                .collect(Collectors.joining(System.lineSeparator()));
+        } catch (IOException e) {
+            logger.error("Error while generating XACML policy for coordination directive", e);
+        }
+        return xacmlPolicy;
+    }
+
+}