Add MDC Topic Filtering

A feature to provide configurable properties for network topics
to extrac fields from JSON strings and place them in a mapped
diagnostic context.

Issue-ID: POLICY-1499
Change-Id: Icfca0be3b263ccf1612b79ed617e2b1ffb0317e6
Signed-off-by: Daniel Cruz <dc443y@att.com>

7 files changed, 658 insertions, 0 deletions

diff --git a/feature-mdc-filters/src/main/feature/config/feature-mdc-filters.properties b/feature-mdc-filters/src/main/feature/config/feature-mdc-filters.properties
new file mode 100755
index 00000000..0a53a9f5
--- /dev/null
+++ b/feature-mdc-filters/src/main/feature/config/feature-mdc-filters.properties
@@ -0,0 +1,54 @@
+###

+# ============LICENSE_START=======================================================

+# feature-mdc-filters

+# ================================================================================

+# 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=========================================================

+###

+

+# The properties keys follow the controller topic configurations followed by a

+# a new topic property, 'mdcFilters'.

+#<protocol>.<type>.topics.<topic-name>.mdcFilters

+

+# The value of the property is broken down to the MDC key name to be used by the 

+# feature followed by the path(s) to the desired field's value.

+#dmaap.sink.topics.example.mdcFilters=sampleKey=$.path.to.sample.key

+

+# The path always begins with '$' as this signifies the root of the JSON document.

+# The underlying library used is Jayway JsonPath. The library's query syntax is 

+# supported for searching a JSON document. The query syntax and some examples 

+# can be found at: https://github.com/json-path/JsonPath

+

+# Multiple fields can be found for a given JSON document by a comma separated list

+# of <mdcKey,jsonPath> pairs.

+#dmaap.sink.topics.example.mdcFilters=field1=$.field1,field2=$.field2

+

+# If a given topic supports multiple message types that have fields with the same

+# name, a '|' separated list can define multiple paths to a field. The feature

+# will loop through each path until it finds a match and returns it.

+#dmaap.sink.topics.example.mdcFilters=field1=$.field1|$.body.field1

+

+# dmaap source filters

+dmaap.source.topics.PDPD-CONFIGURATION.mdcFilters=requestID=$.requestID

+dmaap.source.topics.DCAE_TOPIC.mdcFilters=requestID=$.requestID

+dmaap.source.topics.APPC-CL.mdcFilters=requestID=$.CommonHeader.RequestID

+dmaap.source.topics.APPC-LCM-WRITE.mdcFilters=requestID=$.body.output.common-header.request-id

+dmaap.source.topics.SDNR-CL-RSP.mdcFilters=requestID=$.body.CommonHeader.RequestID

+

+# dmaap sink filters

+dmaap.sink.topics.POLICY-CL-MGT.mdcFilters=requestID=$.requestID

+dmaap.sink.topics.APPC-CL.mdcFilters=requestID=$.CommonHeader.RequestID

+dmaap.sink.topics.APPC-LCM-READ.mdcFilters=requestID=$.body.input.common-header.request-id

+dmaap.sink.topics.SDNR-CL.mdcFilters=requestID=$.body.CommonHeader.RequestID

diff --git a/feature-mdc-filters/src/main/feature/install/disable b/feature-mdc-filters/src/main/feature/install/disable
new file mode 100755
index 00000000..25d57374
--- /dev/null
+++ b/feature-mdc-filters/src/main/feature/install/disable
@@ -0,0 +1,32 @@
+#!/bin/bash
+
+###
+# ============LICENSE_START=======================================================
+# feature-mdc-filters
+# ================================================================================
+# 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=========================================================
+##
+
+if [[ "${DEBUG}" == "y" ]]; then
+    set -x
+fi
+
+CONFIG_DIR="${POLICY_HOME}"/config
+for mainConfig in ${CONFIG_DIR}/logback.xml ${CONFIG_DIR}/logback-eelf.xml; do
+    if [ -e "${mainConfig}" ]; then
+        sed -i --follow-symlinks 's/${abstractNetworkPattern}/${networkPattern}/' "${mainConfig}"
+    fi
+done
diff --git a/feature-mdc-filters/src/main/feature/install/enable b/feature-mdc-filters/src/main/feature/install/enable
new file mode 100755
index 00000000..57c7cc4a
--- /dev/null
+++ b/feature-mdc-filters/src/main/feature/install/enable
@@ -0,0 +1,32 @@
+#!/bin/bash
+
+###
+# ============LICENSE_START=======================================================
+# feature-mdc-filters
+# ================================================================================
+# Copyright (C) 2019 AT&T Intellectual Property. All rights reserved.
+# ================================================================================
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+# 
+#      http://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ============LICENSE_END=========================================================
+##
+
+if [[ "${DEBUG}" == "y" ]]; then
+    set -x
+fi
+
+CONFIG_DIR="${POLICY_HOME}"/config
+for mainConfig in ${CONFIG_DIR}/logback.xml ${CONFIG_DIR}/logback-eelf.xml; do
+    if [ -e "${mainConfig}" ]; then
+        sed -i --follow-symlinks 's/${networkPattern}/${abstractNetworkPattern}/' "${mainConfig}"
+    fi
+done
diff --git a/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcFilterFeature.java b/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcFilterFeature.java
new file mode 100755
index 00000000..369c0aa0
--- /dev/null
+++ b/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcFilterFeature.java
@@ -0,0 +1,201 @@
+/*

+ * ============LICENSE_START=======================================================

+ * feature-mdc-filters

+ * ================================================================================

+ * 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.drools.mdc.filters;

+

+import java.util.HashMap;

+import java.util.List;

+import java.util.Map;

+import java.util.Properties;

+import org.onap.policy.common.endpoints.event.comm.Topic;

+import org.onap.policy.common.endpoints.event.comm.Topic.CommInfrastructure;

+import org.onap.policy.common.endpoints.features.NetLoggerFeatureApi;

+import org.onap.policy.common.endpoints.utils.NetLoggerUtil.EventType;

+import org.onap.policy.drools.features.PolicyControllerFeatureAPI;

+import org.onap.policy.drools.persistence.SystemPersistence;

+import org.onap.policy.drools.system.PolicyController;

+import org.slf4j.Logger;

+import org.slf4j.LoggerFactory;

+import org.slf4j.MDC;

+

+public class MdcFilterFeature implements NetLoggerFeatureApi, PolicyControllerFeatureAPI {

+

+    /**

+     * Logger.

+     */

+    private static final Logger logger = LoggerFactory.getLogger(MdcFilterFeature.class);

+

+    /**

+     * Feature properties.

+     */

+    public static final String FEATURE_NAME = "feature-mdc-filters";

+    public static final String SOURCE = "source";

+    public static final String SINK = "sink";

+    public static final String MDC_FILTERS = ".mdcFilters";

+

+    /**

+     * Mapping of 'protocol:type:topic' key to a 'MdcTopicFilter' object.

+     */

+    private Map<String, MdcTopicFilter> topicFilters = new HashMap<>();

+

+    /**

+     * Feature properties map obtained from the feature properties file.

+     */

+    private Properties featureProps = null;

+

+    /**

+     * Constructor.

+     */

+    public MdcFilterFeature() {

+        super();

+        featureProps = getFeatureProps();

+    }

+

+    /**

+     * Gets the feature properties.

+     *

+     * @return the properties for this feature.

+     */

+    protected Properties getFeatureProps() {

+        return SystemPersistence.manager.getProperties(FEATURE_NAME);

+    }

+

+    /**

+     * Sequence number to be used for order of feature implementer execution.

+     */

+    @Override

+    public int getSequenceNumber() {

+        return 1;

+    }

+

+    /**

+     * Loops through all source and sink topics to find which topics have mdc filters and

+     * inserts an MdcTopicFilter in to the topicFilters map.

+     */

+    @Override

+    public boolean afterCreate(PolicyController controller) {

+        createSourceTopicFilters(controller);

+        createSinkTopicFilters(controller);

+        return false;

+    }

+

+    /**

+     * Extracts the fields in a JSON string that are to be logged in an abbreviated

+     * message. The event delivery infrastructure details are put in the MDC as well using

+     * the keys networkEventType (IN/OUT), networkProtocol (UEB/DMAAP/NOOP/REST), and

+     * networkTopic.

+     */

+    @Override

+    public boolean beforeLog(Logger eventLogger, EventType type, CommInfrastructure protocol, String topic,

+                    String message) {

+

+        String filterKey = null;

+        if (type == EventType.IN) {

+            filterKey = getTopicKey(protocol.name().toLowerCase(), SOURCE, topic);

+        } else {

+            filterKey = getTopicKey(protocol.name().toLowerCase(), SINK, topic);

+        }

+

+        MDC.put("networkEventType", type.name());

+        MDC.put("networkProtocol", protocol.name());

+        MDC.put("networkTopic", topic);

+

+        MdcTopicFilter filter = topicFilters.get(filterKey);

+        if (filter != null) {

+            for (Map.Entry<String, List<String>> entry : filter.find(message).entrySet()) {

+                String mdcKey = entry.getKey();

+                List<String> results = entry.getValue();

+                if (results.isEmpty()) {

+                    logger.debug("No results found for key {}", mdcKey);

+                } else if (results.size() > 1) {

+                    logger.debug("Multple results found for key {}, returning list as a string", mdcKey);

+                    MDC.put(mdcKey, results.toString());

+                } else {

+                    MDC.put(mdcKey, results.get(0));

+                }

+            }

+        } else {

+            logger.debug("No mdc topic filters exist for key {}", filterKey);

+        }

+

+        return false;

+    }

+

+    /**

+     * Clears the MDC mapping after a message is logged.

+     */

+    @Override

+    public boolean afterLog(Logger eventLogger, EventType type, CommInfrastructure protocol, String topic,

+                    String message) {

+        MDC.clear();

+        return false;

+    }

+

+    /**

+     * Creates a key using the protocol, type, and topic name.

+     *

+     * @param protocol defined as ueb, dmaap, noop

+     * @param type defined as source or sink

+     * @param topic name of the topic

+     * @return a key that is the concatenation of the protocol, type, and topic name

+     */

+    private String getTopicKey(String protocol, String type, String topic) {

+        return protocol + ":" + type + ":" + topic;

+    }

+

+    /**

+     * Creates MdcTopicFilters for a source/sink topic based on the type.

+     *

+     * @param topic the topic name

+     * @param type 'source' or 'sink'

+     */

+    private void createTopicFilter(Topic topic, String type) {

+        String protocol = topic.getTopicCommInfrastructure().name().toLowerCase();

+        String topicName = topic.getTopic();

+

+        String propertyKey = protocol + "." + type + ".topics." + topicName + MDC_FILTERS;

+        String propertyValue = featureProps.getProperty(propertyKey);

+        if (propertyValue != null) {

+            String topicKey = getTopicKey(protocol, type, topicName);

+            if (!topicFilters.containsKey(topicKey)) {

+                logger.debug("MdcTopicFilter created for {} {} topic {}", protocol, type, topicName);

+                topicFilters.put(topicKey, new MdcTopicFilter(propertyValue));

+            } else {

+                logger.debug("An MdcTopicFilter already exists for key {}", topicKey);

+            }

+        } else {

+            logger.debug("No MDC filters defined for {} {} topic {}", protocol, type, topicName);

+        }

+    }

+

+    /**

+     * Creates MdcTopicFilters for the controller's source topics.

+     */

+    private void createSourceTopicFilters(PolicyController controller) {

+        controller.getTopicSources().forEach(sourceTopic -> createTopicFilter(sourceTopic, SOURCE));

+    }

+

+    /**

+     * Creates MdcTopicFilters for the controller's sink topics.

+     */

+    private void createSinkTopicFilters(PolicyController controller) {

+        controller.getTopicSinks().forEach(sinkTopic -> createTopicFilter(sinkTopic, SINK));

+    }

+}

diff --git a/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcTopicFilter.java b/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcTopicFilter.java
new file mode 100755
index 00000000..d0813a93
--- /dev/null
+++ b/feature-mdc-filters/src/main/java/org/onap/policy/drools/mdc/filters/MdcTopicFilter.java
@@ -0,0 +1,337 @@
+/*

+ * ============LICENSE_START=======================================================

+ * feature-mdc-filters

+ * ================================================================================

+ * 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.drools.mdc.filters;

+

+import java.util.ArrayList;

+import java.util.Arrays;

+import java.util.HashMap;

+import java.util.List;

+import java.util.Map;

+import org.onap.policy.drools.protocol.coders.JsonProtocolFilter;

+import org.slf4j.Logger;

+import org.slf4j.LoggerFactory;

+

+public class MdcTopicFilter {

+

+    private static final Logger logger = LoggerFactory.getLogger(MdcTopicFilter.class);

+

+    public static final String MDC_KEY_ERROR = "mdcKey must be provided";

+    public static final String JSON_PATH_ERROR = "json path(s) must be provided";

+

+    private Map<String, FilterRule> rules = new HashMap<>();

+

+    public static class FilterRule {

+        private String mdcKey;

+        private List<String> paths;

+

+        public FilterRule(String mdcKey, String path) {

+            this.mdcKey = mdcKey;

+            this.paths = Arrays.asList(path);

+        }

+

+        /**

+         * Constructor.

+         *

+         * @param mdcKey the key to the filter rule

+         * @param paths the list of potential paths to the key

+         */

+        public FilterRule(String mdcKey, List<String> paths) {

+            this.mdcKey = mdcKey;

+            this.paths = paths;

+        }

+

+        public String getMdcKey() {

+            return mdcKey;

+        }

+

+        public List<String> getPaths() {

+            return paths;

+        }

+

+        protected void setMdcKey(String mdcKey) {

+            if (mdcKey == null || mdcKey.isEmpty()) {

+                throw new IllegalArgumentException(MDC_KEY_ERROR);

+            }

+            this.mdcKey = mdcKey;

+        }

+

+        protected void setPaths(List<String> paths) {

+            if (paths == null || paths.isEmpty()) {

+                throw new IllegalArgumentException(JSON_PATH_ERROR);

+            }

+            this.paths = paths;

+        }

+

+        protected void addPaths(List<String> paths) {

+            if (paths == null || paths.isEmpty()) {

+                throw new IllegalArgumentException(JSON_PATH_ERROR);

+            }

+            this.paths.addAll(paths);

+        }

+

+        protected void addPath(String path) {

+            if (path == null || path.isEmpty()) {

+                throw new IllegalArgumentException(JSON_PATH_ERROR);

+            }

+            this.paths.add(path);

+        }

+    }

+

+    protected MdcTopicFilter(String rawFilters) {

+        for (String filter : rawFilters.split("\\s*,\\s*")) {

+            FilterRule rule = createFilterRule(filter);

+            rules.put(rule.mdcKey, rule);

+        }

+    }

+

+    private FilterRule createFilterRule(String filter) {

+        String[] filterKeyPaths = filter.split("\\s*=\\s*");

+        if (filterKeyPaths.length != 2) {

+            throw new IllegalArgumentException("could not parse filter rule");

+        }

+

+        String filterKey = filterKeyPaths[0];

+        String paths = filterKeyPaths[1];

+        List<String> filterPaths = new ArrayList<>(Arrays.asList(paths.split("(?<!\\|)\\|(?!\\|)")));

+        return new FilterRule(filterKey, filterPaths);

+    }

+

+    /**

+     * Gets all the filter rules for the topic.

+     *

+     * @return an array list of the rules for the topic

+     */

+    protected List<FilterRule> getFilterRule() {

+        return new ArrayList<>(rules.values());

+    }

+

+    /**

+     * Gets the filter rule for the specified key.

+     *

+     * @param mdcKey the key to the filter rule

+     * @return the filter rule associated with the key

+     */

+    protected FilterRule getFilterRule(String mdcKey) {

+        if (mdcKey == null || mdcKey.isEmpty()) {

+            throw new IllegalArgumentException(MDC_KEY_ERROR);

+        }

+        return rules.get(mdcKey);

+    }

+

+    /**

+     * Adds a filter rule for the specified key and path.

+     *

+     * @param mdcKey the key to the filter rule

+     * @param path the json path to the key

+     * @return the filter rule that was added for the topic

+     */

+    protected FilterRule addFilterRule(String mdcKey, String path) {

+        if (path == null || path.isEmpty()) {

+            throw new IllegalArgumentException(JSON_PATH_ERROR);

+        }

+        return addFilterRule(mdcKey, Arrays.asList(path));

+    }

+

+    /**

+     * Adds a filter rule for the specified key and paths.

+     *

+     * @param mdcKey the key to the filter rule

+     * @param paths the list of potential paths to the key

+     * @return the filter rule that was added for the topic

+     */

+    protected FilterRule addFilterRule(String mdcKey, List<String> paths) {

+        if (mdcKey == null || mdcKey.isEmpty()) {

+            throw new IllegalArgumentException(MDC_KEY_ERROR);

+        }

+

+        if (paths == null || paths.isEmpty()) {

+            throw new IllegalArgumentException(JSON_PATH_ERROR);

+        }

+

+        if (rules.containsKey(mdcKey)) {

+            throw new IllegalArgumentException("a filter rule already exists for key: " + mdcKey);

+        }

+

+        FilterRule rule = new FilterRule(mdcKey, paths);

+        rules.put(mdcKey, rule);

+        return rule;

+    }

+

+    /**

+     * Modifies an existing filter rule by adding the specified path.

+     *

+     * @param mdcKey the key to the filter rule

+     * @param path the path to the key

+     * @return the filter rule that was modified

+     */

+    protected FilterRule modifyFilterRule(String mdcKey, String path) {

+        if (path == null || path.isEmpty()) {

+            throw new IllegalArgumentException(JSON_PATH_ERROR);

+        }

+        return modifyFilterRule(mdcKey, Arrays.asList(path));

+    }

+

+    /**

+     * Modifies an existing filter rule by adding the specified paths.

+     *

+     * @param mdcKey the key to the filter rule

+     * @param paths the list of potential paths to the key

+     * @return the filter rule that was modified

+     */

+    protected FilterRule modifyFilterRule(String mdcKey, List<String> paths) {

+        if (mdcKey == null || mdcKey.isEmpty()) {

+            throw new IllegalArgumentException(MDC_KEY_ERROR);

+        }

+

+        if (paths == null || paths.isEmpty()) {

+            throw new IllegalArgumentException(JSON_PATH_ERROR);

+        }

+

+        if (!rules.containsKey(mdcKey)) {

+            throw new IllegalArgumentException("a filter rule doesn't exist for key: " + mdcKey);

+        }

+

+        FilterRule rule = rules.get(mdcKey);

+        rule.addPaths(paths);

+        return rule;

+    }

+

+    /**

+     * Modifies an existing filter rule's key and replaces the paths with the specified

+     * paths.

+     *

+     * @param oldMdcKey the old key to the filter rule

+     * @param newMdcKey the new key to the filter rule

+     * @param paths the list of potential paths to the key

+     * @return the filter rule that was modified

+     */

+    protected FilterRule modifyFilterRule(String oldMdcKey, String newMdcKey, List<String> paths) {

+        if (oldMdcKey == null || oldMdcKey.isEmpty()) {

+            throw new IllegalArgumentException("current mdcKey must be provided");

+        }

+

+        if (newMdcKey == null || newMdcKey.isEmpty()) {

+            throw new IllegalArgumentException("new mdcKey must be provided");

+        }

+

+        if (oldMdcKey.equals(newMdcKey)) {

+            throw new IllegalArgumentException("the old and new mdcKey are equivalent");

+        }

+        if (paths == null || paths.isEmpty()) {

+            throw new IllegalArgumentException(JSON_PATH_ERROR);

+        }

+

+        if (rules.containsKey(newMdcKey)) {

+            throw new IllegalArgumentException("a filter rule already exists for key: " + newMdcKey);

+        }

+

+        FilterRule rule = rules.remove(oldMdcKey);

+        if (rule == null) {

+            throw new IllegalArgumentException("a filter rule doesn't exist for key: " + oldMdcKey);

+        }

+

+        rule.setMdcKey(newMdcKey);

+        rule.setPaths(paths);

+        rules.put(newMdcKey, rule);

+        return rule;

+    }

+

+    /**

+     * Deletes all filter rules for the topic filter.

+     */

+    protected void deleteFilterRule() {

+        rules.clear();

+    }

+

+    /**

+     * Deletes an existing filter rule.

+     *

+     * @param mdcKey the key to the filter rule

+     * @return the filter rule that was deleted

+     */

+    protected FilterRule deleteFilterRule(String mdcKey) {

+        if (mdcKey == null || mdcKey.isEmpty()) {

+            throw new IllegalArgumentException(MDC_KEY_ERROR);

+        }

+        return rules.remove(mdcKey);

+    }

+

+    /**

+     * Finds all fields for each topic filter rule. The results are stored in a map that

+     * is indexed by the MDC key. Each MDC key has a list of results as multiple

+     * occurrences of a key can be found in a JSON document.

+     *

+     * @param json the json string to be parsed

+     * @return a map of mdc keys and list of results for each key

+     */

+    protected Map<String, List<String>> find(String json) {

+        Map<String, List<String>> results = new HashMap<>();

+        for (FilterRule rule : rules.values()) {

+            List<String> matches = new ArrayList<>();

+            for (String path : rule.getPaths()) {

+

+                try {

+                    matches = JsonProtocolFilter.filter(json, path);

+                } catch (Exception e) {

+                    logger.debug("Could not filter on path {} because of {}", path, e.getMessage(), e);

+                }

+

+                if (!matches.isEmpty()) {

+                    break;

+                } else {

+                    logger.error("Could not find path {} in json {}", path, json);

+                }

+

+            }

+            results.put(rule.getMdcKey(), matches);

+        }

+        return results;

+    }

+

+    /**

+     * Finds all occurrences of a field in a JSON document based on the filter rule paths.

+     *

+     * @param json the json string to be parsed

+     * @return a list of matches from the JSON document

+     */

+    protected List<String> find(String json, String mdcKey) {

+        List<String> matches = new ArrayList<>();

+        for (String path : rules.get(mdcKey).getPaths()) {

+

+            try {

+                matches = JsonProtocolFilter.filter(json, path);

+            } catch (Exception e) {

+                logger.debug("Could not filter on path {} because of {}", path, e.getMessage(), e);

+            }

+

+            if (!matches.isEmpty()) {

+                break;

+            }

+

+        }

+

+        if (matches.isEmpty()) {

+            logger.error("Could not find any matches for key {} in json {}", mdcKey, json);

+        }

+

+        return matches;

+    }

+}

diff --git a/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.common.endpoints.features.NetLoggerFeatureApi b/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.common.endpoints.features.NetLoggerFeatureApi
new file mode 100755
index 00000000..f2fdb402
--- /dev/null
+++ b/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.common.endpoints.features.NetLoggerFeatureApi
@@ -0,0 +1 @@
+org.onap.policy.drools.mdc.filters.MdcFilterFeature

diff --git a/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.drools.features.PolicyControllerFeatureAPI b/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.drools.features.PolicyControllerFeatureAPI
new file mode 100755
index 00000000..f2fdb402
--- /dev/null
+++ b/feature-mdc-filters/src/main/resources/META-INF/services/org.onap.policy.drools.features.PolicyControllerFeatureAPI
@@ -0,0 +1 @@
+org.onap.policy.drools.mdc.filters.MdcFilterFeature