[ONOS-4438] Add codecs for mastership REST API

Add codecs for RoleInfo, MastershipTerm and MastershipRole.

Change-Id: I1135c7fc0ed591446d6268229b54fda70391fdb9

@@ -23,6 +23,7 @@ import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Service;
 import org.apache.felix.scr.annotations.Service;
 import org.onlab.packet.Ethernet;
 import org.onlab.packet.Ethernet;
 import org.onosproject.cluster.ControllerNode;
 import org.onosproject.cluster.ControllerNode;
+import org.onosproject.cluster.RoleInfo;
 import org.onosproject.codec.CodecService;
 import org.onosproject.codec.CodecService;
 import org.onosproject.codec.JsonCodec;
 import org.onosproject.codec.JsonCodec;
 import org.onosproject.core.Application;
 import org.onosproject.core.Application;
@@ -31,12 +32,14 @@ import org.onosproject.incubator.net.virtual.VirtualDevice;
 import org.onosproject.incubator.net.virtual.VirtualLink;
 import org.onosproject.incubator.net.virtual.VirtualLink;
 import org.onosproject.incubator.net.virtual.VirtualNetwork;
 import org.onosproject.incubator.net.virtual.VirtualNetwork;
 import org.onosproject.incubator.net.virtual.VirtualPort;
 import org.onosproject.incubator.net.virtual.VirtualPort;
+import org.onosproject.mastership.MastershipTerm;
 import org.onosproject.net.Annotations;
 import org.onosproject.net.Annotations;
 import org.onosproject.net.ConnectPoint;
 import org.onosproject.net.ConnectPoint;
 import org.onosproject.net.Device;
 import org.onosproject.net.Device;
 import org.onosproject.net.Host;
 import org.onosproject.net.Host;
 import org.onosproject.net.HostLocation;
 import org.onosproject.net.HostLocation;
 import org.onosproject.net.Link;
 import org.onosproject.net.Link;
+import org.onosproject.net.MastershipRole;
 import org.onosproject.net.Path;
 import org.onosproject.net.Path;
 import org.onosproject.net.Port;
 import org.onosproject.net.Port;
 import org.onosproject.net.device.PortStatistics;
 import org.onosproject.net.device.PortStatistics;
@@ -136,6 +139,9 @@ public class CodecManager implements CodecService {
         registerCodec(VirtualDevice.class, new VirtualDeviceCodec());
         registerCodec(VirtualDevice.class, new VirtualDeviceCodec());
         registerCodec(VirtualPort.class, new VirtualPortCodec());
         registerCodec(VirtualPort.class, new VirtualPortCodec());
         registerCodec(VirtualLink.class, new VirtualLinkCodec());
         registerCodec(VirtualLink.class, new VirtualLinkCodec());
+        registerCodec(MastershipTerm.class, new MastershipTermCodec());
+        registerCodec(MastershipRole.class, new MastershipRoleCodec());
+        registerCodec(RoleInfo.class, new RoleInfoCodec());
         log.info("Started");
         log.info("Started");
     }
     }
 
 

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.net.MastershipRole;
+import org.slf4j.Logger;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onlab.util.Tools.nullIsIllegal;
+import static org.onosproject.net.MastershipRole.MASTER;
+import static org.onosproject.net.MastershipRole.NONE;
+import static org.onosproject.net.MastershipRole.STANDBY;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Codec for mastership role.
+ */
+public final class MastershipRoleCodec extends JsonCodec<MastershipRole> {
+    private final Logger log = getLogger(getClass());
+
+    // JSON field names
+    private static final String ROLE = "role";
+
+    private static final String MISSING_MEMBER_MESSAGE = " member is required in MastershipRole";
+
+    @Override
+    public ObjectNode encode(MastershipRole mastershipRole, CodecContext context) {
+        checkNotNull(mastershipRole, "MastershipRole cannot be null");
+        ObjectNode result = context.mapper().createObjectNode()
+                .put(ROLE, mastershipRole.name());
+        return result;
+    }
+
+    @Override
+    public MastershipRole decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        String roleJson = nullIsIllegal(json.get(ROLE),
+                ROLE + MISSING_MEMBER_MESSAGE).asText();
+        MastershipRole mastershipRole;
+        switch (roleJson) {
+            case "MASTER":
+                mastershipRole = MASTER;
+                break;
+            case "STANDBY":
+                mastershipRole = STANDBY;
+                break;
+            case "NONE":
+                mastershipRole = NONE;
+                break;
+            default:
+                log.warn("The mastership role {} is not defined.", roleJson);
+                return null;
+        }
+
+        return mastershipRole;
+    }
+}

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.mastership.MastershipTerm;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onlab.util.Tools.nullIsIllegal;
+
+/**
+ * Codec for mastership term.
+ */
+public class MastershipTermCodec extends JsonCodec<MastershipTerm> {
+
+    // JSON field names
+    private static final String MASTER = "master";
+    private static final String TERM_NUMBER = "termNumber";
+
+    private static final String MISSING_MEMBER_MESSAGE = " member is required in MastershipTerm";
+
+    @Override
+    public ObjectNode encode(MastershipTerm term, CodecContext context) {
+        checkNotNull(term, "Mastership term cannot be null");
+        ObjectNode result = context.mapper().createObjectNode()
+                .put(MASTER, term.master().id())
+                .put(TERM_NUMBER, term.termNumber());
+
+        return result;
+    }
+
+    @Override
+    public MastershipTerm decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        // node identifier of master
+        NodeId nodeId = NodeId.nodeId(nullIsIllegal(json.get(MASTER),
+                MASTER + MISSING_MEMBER_MESSAGE).asText());
+
+        // term number
+        long termNumber = nullIsIllegal(json.get(TERM_NUMBER),
+                TERM_NUMBER + MISSING_MEMBER_MESSAGE).asLong();
+
+        return MastershipTerm.of(nodeId, termNumber);
+    }
+}

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.cluster.RoleInfo;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.IntStream;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onlab.util.Tools.nullIsIllegal;
+
+/**
+ * Codec for role info.
+ */
+public final class RoleInfoCodec extends JsonCodec<RoleInfo> {
+
+    // JSON field names
+    private static final String MASTER = "master";
+    private static final String BACKUPS = "backups";
+
+    private static final String MISSING_MEMBER_MESSAGE = " member is required in MastershipTerm";
+
+    @Override
+    public ObjectNode encode(RoleInfo roleInfo, CodecContext context) {
+        checkNotNull(roleInfo, "RoleInfo cannot be null");
+
+        ObjectNode result = context.mapper().createObjectNode();
+
+        if (roleInfo.master() != null) {
+            result.put(MASTER, roleInfo.master().id());
+        }
+
+        ArrayNode backups = context.mapper().createArrayNode();
+        roleInfo.backups().forEach(backup -> backups.add(backup.id()));
+
+        if (roleInfo.backups().size() != 0) {
+            result.set(BACKUPS, backups);
+        }
+
+        return result;
+    }
+
+    @Override
+    public RoleInfo decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        // parse node identifier of master
+        NodeId nodeId = json.get(MASTER) == null ?
+                null : NodeId.nodeId(json.get(MASTER).asText());
+
+        // parse node identifier of backups
+        List<NodeId> backups = new ArrayList<>();
+
+        ArrayNode backupsJson = (ArrayNode) nullIsIllegal(json.get(BACKUPS),
+                BACKUPS + MISSING_MEMBER_MESSAGE);
+
+        IntStream.range(0, backupsJson.size()).forEach(i -> {
+            JsonNode backupJson = nullIsIllegal(backupsJson.get(i),
+                    "Backup node id cannot be null");
+            backups.add(NodeId.nodeId(backupJson.asText()));
+        });
+
+        return new RoleInfo(nodeId, backups);
+    }
+}

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.hamcrest.Description;
+import org.hamcrest.TypeSafeDiagnosingMatcher;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.net.MastershipRole;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+import static org.onosproject.net.MastershipRole.MASTER;
+
+/**
+ * Unit tests for mastership role codec.
+ */
+public final class MastershipRoleCodecTest {
+
+    MockCodecContext context;
+    JsonCodec<MastershipRole> mastershipRoleCodec;
+
+    /**
+     * Sets up for each test. Creates a context and fetches the mastership role
+     * codec.
+     */
+    @Before
+    public void setUp() {
+        context = new MockCodecContext();
+        mastershipRoleCodec = context.codec(MastershipRole.class);
+        assertThat(mastershipRoleCodec, notNullValue());
+    }
+
+    /**
+     * Tests encoding of a mastership role object.
+     */
+    @Test
+    public void testMastershipRoleEncode() {
+        MastershipRole mastershipRole = MASTER;
+        ObjectNode mastershipRoleJson = mastershipRoleCodec.encode(mastershipRole, context);
+        assertThat(mastershipRoleJson, MastershipRoleJsonMatcher.matchesMastershipRole(mastershipRole));
+    }
+
+    /**
+     * Tests decoding of mastership role JSON object.
+     */
+    @Test
+    public void testMastershipRoleDecode() throws IOException {
+        MastershipRole mastershipRole = getMastershipRole("MastershipRole.json");
+
+        assertThat(mastershipRole, is(MASTER));
+    }
+
+    /**
+     * Hamcrest matcher for mastership role.
+     */
+    private static final class MastershipRoleJsonMatcher extends TypeSafeDiagnosingMatcher<JsonNode> {
+
+        private final MastershipRole mastershipRole;
+
+        private MastershipRoleJsonMatcher(MastershipRole mastershipRole) {
+            this.mastershipRole = mastershipRole;
+        }
+
+        @Override
+        protected boolean matchesSafely(JsonNode jsonNode, Description description) {
+
+            // check mastership role
+            String jsonRole = jsonNode.get("role").asText();
+            String role = mastershipRole.name();
+            if (!jsonRole.equals(role)) {
+                description.appendText("mastership role was " + jsonRole);
+                return false;
+            }
+
+            return true;
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText(mastershipRole.toString());
+        }
+
+        static MastershipRoleJsonMatcher matchesMastershipRole(MastershipRole mastershipRole) {
+            return new MastershipRoleJsonMatcher(mastershipRole);
+        }
+    }
+
+    /**
+     * Reads in a mastership role from the given resource and decodes it.
+     *
+     * @param resourceName resource to use to read the JSON for the rule
+     * @return decoded mastership term object
+     * @throws IOException if processing the resource fails
+     */
+    private MastershipRole getMastershipRole(String resourceName) throws IOException {
+        InputStream jsonStream = MastershipRoleCodecTest.class.getResourceAsStream(resourceName);
+        JsonNode json = context.mapper().readTree(jsonStream);
+        assertThat(json, notNullValue());
+        MastershipRole mastershipRole = mastershipRoleCodec.decode((ObjectNode) json, context);
+        assertThat(mastershipRole, notNullValue());
+        return mastershipRole;
+    }
+}

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.hamcrest.Description;
+import org.hamcrest.TypeSafeDiagnosingMatcher;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.mastership.MastershipTerm;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+
+/**
+ * Unit tests for mastership term codec.
+ */
+public class MastershipTermCodecTest {
+
+    MockCodecContext context;
+    JsonCodec<MastershipTerm> mastershipTermCodec;
+
+    /**
+     * Sets up for each test. Creates a context and fetches the mastership term
+     * codec.
+     */
+    @Before
+    public void setUp() {
+        context = new MockCodecContext();
+        mastershipTermCodec = context.codec(MastershipTerm.class);
+        assertThat(mastershipTermCodec, notNullValue());
+    }
+
+    /**
+     * Tests encoding of a mastership term object.
+     */
+    @Test
+    public void testMastershipTermEncode() {
+        NodeId masterNodeId = NodeId.nodeId("1");
+        long termNumber = 10;
+
+        MastershipTerm mastershipTerm = MastershipTerm.of(masterNodeId, termNumber);
+        ObjectNode mastershipTermJson = mastershipTermCodec.encode(mastershipTerm, context);
+        assertThat(mastershipTermJson, MastershipTermJsonMatcher.matchesMastershipTerm(mastershipTerm));
+    }
+
+    /**
+     * Tests decoding of mastership term JSON object.
+     */
+    @Test
+    public void testMastershipTermDecode() throws IOException {
+        MastershipTerm mastershipTerm = getMastershipTerm("MastershipTerm.json");
+
+        assertThat(mastershipTerm.master().id(), is("1"));
+        assertThat(mastershipTerm.termNumber(), is(10L));
+    }
+
+    /**
+     * Hamcrest matcher for mastership term.
+     */
+    private static final class MastershipTermJsonMatcher extends TypeSafeDiagnosingMatcher<JsonNode> {
+
+        private final MastershipTerm mastershipTerm;
+
+        private MastershipTermJsonMatcher(MastershipTerm mastershipTerm) {
+            this.mastershipTerm = mastershipTerm;
+        }
+
+        @Override
+        protected boolean matchesSafely(JsonNode jsonNode, Description description) {
+
+            // check node identifier of master
+            String jsonNodeId = jsonNode.get("master").asText();
+            String nodeId = mastershipTerm.master().id();
+            if (!jsonNodeId.equals(nodeId)) {
+                description.appendText("master's node id was " + jsonNodeId);
+                return false;
+            }
+
+            // check term number
+            long jsonTermNumber = jsonNode.get("termNumber").asLong();
+            long termNumber = mastershipTerm.termNumber();
+            if (jsonTermNumber != termNumber) {
+                description.appendText("term number was " + jsonTermNumber);
+                return false;
+            }
+
+            return true;
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText(mastershipTerm.toString());
+        }
+
+        static MastershipTermJsonMatcher matchesMastershipTerm(MastershipTerm mastershipTerm) {
+            return new MastershipTermJsonMatcher(mastershipTerm);
+        }
+    }
+
+    /**
+     * Reads in a mastership term from the given resource and decodes it.
+     *
+     * @param resourceName resource to use to read the JSON for the rule
+     * @return decoded mastership term object
+     * @throws IOException if processing the resource fails
+     */
+    private MastershipTerm getMastershipTerm(String resourceName) throws IOException {
+        InputStream jsonStream = MastershipTermCodecTest.class.getResourceAsStream(resourceName);
+        JsonNode json = context.mapper().readTree(jsonStream);
+        assertThat(json, notNullValue());
+        MastershipTerm mastershipTerm = mastershipTermCodec.decode((ObjectNode) json, context);
+        assertThat(mastershipTerm, notNullValue());
+        return mastershipTerm;
+    }
+}

+/*
+ * Copyright 2016-present Open Networking Laboratory
+ *
+ * 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.
+ */
+package org.onosproject.codec.impl;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.google.common.collect.ImmutableList;
+import org.apache.commons.lang3.StringUtils;
+import org.hamcrest.Description;
+import org.hamcrest.TypeSafeDiagnosingMatcher;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.cluster.RoleInfo;
+import org.onosproject.codec.JsonCodec;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+
+/**
+ * Unit tests for role info codec.
+ */
+public final class RoleInfoCodecTest {
+
+    MockCodecContext context;
+    JsonCodec<RoleInfo> roleInfoCodec;
+
+    @Before
+    public void setUp() {
+        context = new MockCodecContext();
+        roleInfoCodec = context.codec(RoleInfo.class);
+        assertThat(roleInfoCodec, notNullValue());
+    }
+
+    /**
+     * Tests encoding of a role info object.
+     */
+    @Test
+    public void testRoleInfoEncode() {
+        NodeId masterNodeId = NodeId.nodeId("1");
+        NodeId backupNodeId1 = NodeId.nodeId("1");
+        NodeId backupNodeId2 = NodeId.nodeId("2");
+        NodeId backupNodeId3 = NodeId.nodeId("3");
+        List<NodeId> backupNodeIds =
+                ImmutableList.of(backupNodeId1, backupNodeId2, backupNodeId3);
+
+        RoleInfo roleInfo = new RoleInfo(masterNodeId, backupNodeIds);
+        ObjectNode roleInfoJson = roleInfoCodec.encode(roleInfo, context);
+        assertThat(roleInfoJson, RoleInfoJsonMatcher.matchesRoleInfo(roleInfo));
+    }
+
+    /**
+     * Tests decoding of a role info JSON object.
+     */
+    @Test
+    public void testRoleInfoDecode() throws IOException {
+        RoleInfo roleInfo = getRoleInfo("RoleInfo.json");
+
+        assertThat(roleInfo.backups().size(), is(3));
+
+        assertThat(roleInfo.master().id(), is("1"));
+
+        List<NodeId> backups = roleInfo.backups();
+        assertThat(backups.contains(NodeId.nodeId("2")), is(true));
+        assertThat(backups.contains(NodeId.nodeId("3")), is(true));
+        assertThat(backups.contains(NodeId.nodeId("4")), is(true));
+    }
+
+    /**
+     * Hamcrest matcher for role info.
+     */
+    private static final class RoleInfoJsonMatcher extends TypeSafeDiagnosingMatcher<JsonNode> {
+
+        private final RoleInfo roleInfo;
+
+        private RoleInfoJsonMatcher(RoleInfo roleInfo) {
+            this.roleInfo = roleInfo;
+        }
+
+        @Override
+        protected boolean matchesSafely(JsonNode jsonNode, Description description) {
+
+            // check master node identifier
+            String jsonNodeId = jsonNode.get("master") != null ? jsonNode.get("master").asText() : null;
+            String nodeId = roleInfo.master().id();
+            if (!StringUtils.equals(jsonNodeId, nodeId)) {
+                description.appendText("master's node id was " + jsonNodeId);
+                return false;
+            }
+
+            // check backup nodes size
+            JsonNode jsonBackupNodeIds = jsonNode.get("backups");
+            if (jsonBackupNodeIds.size() != roleInfo.backups().size()) {
+                description.appendText("backup nodes size was " + jsonBackupNodeIds.size());
+                return false;
+            }
+
+
+            // check backup nodes' identifier
+            for (NodeId backupNodeId : roleInfo.backups()) {
+                boolean backupFound = false;
+                for (int idx = 0; idx < jsonBackupNodeIds.size(); idx++) {
+                    if (backupNodeId.id().equals(jsonBackupNodeIds.get(idx).asText())) {
+                        backupFound = true;
+                        break;
+                    }
+                }
+                if (!backupFound) {
+                    description.appendText("backup not found " + backupNodeId.id());
+                    return false;
+                }
+            }
+
+            return true;
+        }
+
+        @Override
+        public void describeTo(Description description) {
+            description.appendText(roleInfo.toString());
+        }
+
+        /**
+         * Factory to allocate a role info.
+         *
+         * @param roleInfo role info object we are looking for
+         * @return matcher
+         */
+        static RoleInfoJsonMatcher matchesRoleInfo(RoleInfo roleInfo) {
+            return new RoleInfoJsonMatcher(roleInfo);
+        }
+    }
+
+    /**
+     * Reads in a role info from the given resource and decodes it.
+     *
+     * @param resourceName resource to use to read the JSON for the rule
+     * @return decoded roleInfo
+     * @throws IOException if processing the resource fails
+     */
+    private RoleInfo getRoleInfo(String resourceName) throws IOException {
+        InputStream jsonStream = RoleInfoCodecTest.class.getResourceAsStream(resourceName);
+        JsonNode json = context.mapper().readTree(jsonStream);
+        assertThat(json, notNullValue());
+        RoleInfo roleInfo = roleInfoCodec.decode((ObjectNode) json, context);
+        assertThat(roleInfo, notNullValue());
+        return roleInfo;
+    }
+}

+{
+  "role": "MASTER"
+}
\ No newline at end of file

+{
+  "master": "1",
+  "termNumber": 10
+}
\ No newline at end of file

+{
+  "master": "1",
+  "backups": [
+    "2",
+    "3",
+    "4"
+  ]
+}
\ No newline at end of file