Add a Multiple source to single destination intent

This is a very simplistic implementation of an intent that
represents multiple sources with a single destination.
The implementaiton is simple, it just computes the union
of the set of path segments needed to satisfy all the connections
and installs them.

The unit test is just a skeleton with a single test case and
needs to be expanded.

+package org.onlab.onos.cli.net;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import org.apache.karaf.shell.commands.Argument;
+import org.apache.karaf.shell.commands.Command;
+import org.onlab.onos.cli.AbstractShellCommand;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.PortNumber;
+import org.onlab.onos.net.flow.DefaultTrafficSelector;
+import org.onlab.onos.net.flow.DefaultTrafficTreatment;
+import org.onlab.onos.net.flow.TrafficSelector;
+import org.onlab.onos.net.flow.TrafficTreatment;
+import org.onlab.onos.net.intent.Intent;
+import org.onlab.onos.net.intent.IntentId;
+import org.onlab.onos.net.intent.IntentService;
+import org.onlab.onos.net.intent.MultiPointToSinglePointIntent;
+import org.onlab.packet.Ethernet;
+
+/**
+ * Installs point-to-point connectivity intents.
+ */
+@Command(scope = "onos", name = "add-multi-to-single-intent",
+         description = "Installs point-to-point connectivity intent")
+public class AddMultiPointToSinglePointIntentCommand extends AbstractShellCommand {
+
+    @Argument(index = 0, name = "ingressDevices",
+              description = "Ingress Device/Port Description",
+              required = true, multiValued = true)
+    String[] deviceStrings = null;
+
+    private static long id = 0x7070001;
+
+    @Override
+    protected void execute() {
+        IntentService service = get(IntentService.class);
+
+        if (deviceStrings.length < 2) {
+            return;
+        }
+
+        String egressDeviceString = deviceStrings[deviceStrings.length - 1];
+        DeviceId egressDeviceId = DeviceId.deviceId(getDeviceId(egressDeviceString));
+        PortNumber egressPortNumber =
+                PortNumber.portNumber(getPortNumber(egressDeviceString));
+        ConnectPoint egress = new ConnectPoint(egressDeviceId, egressPortNumber);
+        Set<ConnectPoint> ingressPoints = new HashSet<>();
+
+        for (int index = 0; index < deviceStrings.length - 1; index++) {
+            String ingressDeviceString = deviceStrings[index];
+            DeviceId ingressDeviceId = DeviceId.deviceId(getDeviceId(ingressDeviceString));
+            PortNumber ingressPortNumber =
+                    PortNumber.portNumber(getPortNumber(ingressDeviceString));
+            ConnectPoint ingress = new ConnectPoint(ingressDeviceId, ingressPortNumber);
+            ingressPoints.add(ingress);
+        }
+
+
+        TrafficSelector selector = DefaultTrafficSelector.builder()
+                .matchEthType(Ethernet.TYPE_IPV4)
+                .build();
+        TrafficTreatment treatment = DefaultTrafficTreatment.builder().build();
+
+        Intent intent =
+                new MultiPointToSinglePointIntent(new IntentId(id++),
+                                                  selector,
+                                                  treatment,
+                                                  ingressPoints,
+                                                  egress);
+        service.submit(intent);
+    }
+
+    /**
+     * Extracts the port number portion of the ConnectPoint.
+     *
+     * @param deviceString string representing the device/port
+     * @return port number as a string, empty string if the port is not found
+     */
+    private String getPortNumber(String deviceString) {
+        int slash = deviceString.indexOf('/');
+        if (slash <= 0) {
+            return "";
+        }
+        return deviceString.substring(slash + 1, deviceString.length());
+    }
+
+    /**
+     * Extracts the device ID portion of the ConnectPoint.
+     *
+     * @param deviceString string representing the device/port
+     * @return device ID string
+     */
+    private String getDeviceId(String deviceString) {
+        int slash = deviceString.indexOf('/');
+        if (slash <= 0) {
+            return "";
+        }
+        return deviceString.substring(0, slash);
+    }
+}

@@ -83,6 +83,12 @@
             </completers>
         </command>
         <command>
+            <action class="org.onlab.onos.cli.net.AddMultiPointToSinglePointIntentCommand"/>
+            <completers>
+                <ref component-id="connectPointCompleter"/>
+            </completers>
+        </command>
+        <command>
             <action class="org.onlab.onos.cli.net.IntentPushTestCommand"/>
             <completers>
                 <ref component-id="connectPointCompleter"/>

+package org.onlab.onos.net.intent;
+
+import java.util.Collection;
+import java.util.Objects;
+import java.util.Set;
+
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.flow.TrafficSelector;
+import org.onlab.onos.net.flow.TrafficTreatment;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * Abstraction of a connectivity intent that is implemented by a set of path
+ * segments.
+ */
+public class LinkCollectionIntent extends ConnectivityIntent implements InstallableIntent {
+
+    private final Set<Link> links;
+
+    /**
+     * Creates a new point-to-point intent with the supplied ingress/egress
+     * ports and using the specified explicit path.
+     *
+     * @param id          intent identifier
+     * @param selector    traffic match
+     * @param treatment   action
+     * @param links       traversed links
+     * @throws NullPointerException {@code path} is null
+     */
+    public LinkCollectionIntent(IntentId id,
+                                TrafficSelector selector,
+                                TrafficTreatment treatment,
+                                Set<Link> links) {
+        super(id, selector, treatment);
+        this.links = links;
+    }
+
+    protected LinkCollectionIntent() {
+        super();
+        this.links = null;
+    }
+
+    @Override
+    public Collection<Link> requiredLinks() {
+        return links;
+    }
+
+    public Set<Link> links() {
+        return links;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        if (!super.equals(o)) {
+            return false;
+        }
+
+        LinkCollectionIntent that = (LinkCollectionIntent) o;
+
+        return Objects.equals(this.links, that.links);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(super.hashCode(), links);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .add("id", id())
+                .add("match", selector())
+                .add("action", treatment())
+                .add("links", links())
+                .toString();
+    }
+}

+package org.onlab.onos.net.intent.impl;
+
+import java.util.List;
+import java.util.concurrent.Future;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onlab.onos.ApplicationId;
+import org.onlab.onos.CoreService;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.flow.CompletedBatchOperation;
+import org.onlab.onos.net.flow.DefaultFlowRule;
+import org.onlab.onos.net.flow.DefaultTrafficSelector;
+import org.onlab.onos.net.flow.FlowRule;
+import org.onlab.onos.net.flow.FlowRuleBatchEntry;
+import org.onlab.onos.net.flow.FlowRuleBatchEntry.FlowRuleOperation;
+import org.onlab.onos.net.flow.FlowRuleBatchOperation;
+import org.onlab.onos.net.flow.FlowRuleService;
+import org.onlab.onos.net.flow.TrafficSelector;
+import org.onlab.onos.net.flow.TrafficTreatment;
+import org.onlab.onos.net.intent.IntentExtensionService;
+import org.onlab.onos.net.intent.IntentInstaller;
+import org.onlab.onos.net.intent.LinkCollectionIntent;
+import org.onlab.onos.net.intent.PathIntent;
+import org.slf4j.Logger;
+
+import com.google.common.collect.Lists;
+
+import static org.onlab.onos.net.flow.DefaultTrafficTreatment.builder;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Installer for {@link org.onlab.onos.net.intent.LinkCollectionIntent}
+ * path segment intents.
+ */
+@Component(immediate = true)
+public class LinkCollectionIntentInstaller implements IntentInstaller<LinkCollectionIntent> {
+
+    private final Logger log = getLogger(getClass());
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected IntentExtensionService intentManager;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected FlowRuleService flowRuleService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    private ApplicationId appId;
+
+    @Activate
+    public void activate() {
+        appId = coreService.registerApplication("org.onlab.onos.net.intent");
+        intentManager.registerInstaller(LinkCollectionIntent.class, this);
+    }
+
+    @Deactivate
+    public void deactivate() {
+        intentManager.unregisterInstaller(PathIntent.class);
+    }
+
+    /**
+     * Apply a list of FlowRules.
+     *
+     * @param rules rules to apply
+     */
+    private Future<CompletedBatchOperation> applyBatch(List<FlowRuleBatchEntry> rules) {
+        FlowRuleBatchOperation batch = new FlowRuleBatchOperation(rules);
+        return flowRuleService.applyBatch(batch);
+    }
+
+    @Override
+    public Future<CompletedBatchOperation> install(LinkCollectionIntent intent) {
+        TrafficSelector.Builder builder =
+                DefaultTrafficSelector.builder(intent.selector());
+        List<FlowRuleBatchEntry> rules = Lists.newLinkedList();
+        for (Link link : intent.links()) {
+            TrafficTreatment treatment = builder()
+                    .setOutput(link.src().port()).build();
+
+            FlowRule rule = new DefaultFlowRule(link.src().deviceId(),
+                    builder.build(), treatment,
+                    123, appId, 600);
+            rules.add(new FlowRuleBatchEntry(FlowRuleOperation.ADD, rule));
+        }
+
+        return applyBatch(rules);
+    }
+
+    @Override
+    public Future<CompletedBatchOperation> uninstall(LinkCollectionIntent intent) {
+        TrafficSelector.Builder builder =
+                DefaultTrafficSelector.builder(intent.selector());
+        List<FlowRuleBatchEntry> rules = Lists.newLinkedList();
+
+        for (Link link : intent.links()) {
+            TrafficTreatment treatment = builder()
+                    .setOutput(link.src().port()).build();
+            FlowRule rule = new DefaultFlowRule(link.src().deviceId(),
+                    builder.build(), treatment,
+                    123, appId, 600);
+            rules.add(new FlowRuleBatchEntry(FlowRuleOperation.REMOVE, rule));
+        }
+        return applyBatch(rules);
+    }
+}

+package org.onlab.onos.net.intent.impl;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.Path;
+import org.onlab.onos.net.intent.IdGenerator;
+import org.onlab.onos.net.intent.Intent;
+import org.onlab.onos.net.intent.IntentCompiler;
+import org.onlab.onos.net.intent.IntentExtensionService;
+import org.onlab.onos.net.intent.IntentId;
+import org.onlab.onos.net.intent.LinkCollectionIntent;
+import org.onlab.onos.net.intent.MultiPointToSinglePointIntent;
+import org.onlab.onos.net.intent.PointToPointIntent;
+import org.onlab.onos.net.topology.PathService;
+
+/**
+ * An intent compiler for
+ * {@link org.onlab.onos.net.intent.MultiPointToSinglePointIntent}.
+ */
+@Component(immediate = true)
+public class MultiPointToSinglePointIntentCompiler
+        implements IntentCompiler<MultiPointToSinglePointIntent> {
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected IntentExtensionService intentManager;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected PathService pathService;
+
+    private IdGenerator<IntentId> intentIdGenerator;
+
+    @Activate
+    public void activate() {
+        IdBlockAllocator idBlockAllocator = new DummyIdBlockAllocator();
+        intentIdGenerator = new IdBlockAllocatorBasedIntentIdGenerator(idBlockAllocator);
+        intentManager.registerCompiler(MultiPointToSinglePointIntent.class, this);
+    }
+
+    @Deactivate
+    public void deactivate() {
+        intentManager.unregisterCompiler(PointToPointIntent.class);
+    }
+
+    @Override
+    public List<Intent> compile(MultiPointToSinglePointIntent intent) {
+        Set<Link> links = new HashSet<>();
+
+        for (ConnectPoint ingressPoint : intent.ingressPoints()) {
+            Path path = getPath(ingressPoint, intent.egressPoint());
+            links.addAll(path.links());
+        }
+
+        Intent result = new LinkCollectionIntent(intentIdGenerator.getNewId(),
+                intent.selector(), intent.treatment(),
+                links);
+        return Arrays.asList(result);
+    }
+
+    /**
+     * Computes a path between two ConnectPoints.
+     *
+     * @param one start of the path
+     * @param two end of the path
+     * @return Path between the two
+     * @throws org.onlab.onos.net.intent.impl.PathNotFoundException if a path cannot be found
+     */
+    private Path getPath(ConnectPoint one, ConnectPoint two) {
+        Set<Path> paths = pathService.getPaths(one.deviceId(), two.deviceId());
+        if (paths.isEmpty()) {
+            throw new PathNotFoundException("No path from " + one + " to " + two);
+        }
+        // TODO: let's be more intelligent about this eventually
+        return paths.iterator().next();
+    }
+}

+package org.onlab.onos.net.intent;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.junit.Test;
+import org.onlab.onos.net.Link;
+import org.onlab.onos.net.flow.TrafficSelector;
+import org.onlab.onos.net.flow.TrafficTreatment;
+import org.onlab.onos.net.flow.criteria.Criterion;
+import org.onlab.onos.net.flow.instructions.Instruction;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+public class TestLinkCollectionIntent {
+
+    private static class MockSelector implements TrafficSelector {
+        @Override
+        public Set<Criterion> criteria() {
+            return new HashSet<Criterion>();
+        }
+    }
+
+    private static class MockTreatment implements TrafficTreatment {
+        @Override
+        public List<Instruction> instructions() {
+            return new ArrayList<>();
+        }
+    }
+
+    @Test
+    public void testComparison() {
+        TrafficSelector selector = new MockSelector();
+        TrafficTreatment treatment = new MockTreatment();
+        Set<Link> links = new HashSet<>();
+        LinkCollectionIntent i1 = new LinkCollectionIntent(new IntentId(12),
+                selector, treatment, links);
+        LinkCollectionIntent i2 = new LinkCollectionIntent(new IntentId(12),
+                selector, treatment, links);
+
+        assertThat(i1.equals(i2), is(true));
+    }
+
+}