ONOS checkin based on commit tag e796610b1f721d02f9b0e213cf6f7790c10ecd60

Change-Id: Ife8810491034fe7becdba75dda20de4267bd15cd

1 files changed, 190 insertions, 0 deletions

diff --git a/framework/src/onos/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java b/framework/src/onos/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java
new file mode 100644
index 00000000..a238c7fb
--- /dev/null
+++ b/framework/src/onos/core/net/src/main/java/org/onosproject/net/topology/impl/PathManager.java
@@ -0,0 +1,190 @@
+/*
+ * Copyright 2014 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.net.topology.impl;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+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.apache.felix.scr.annotations.Service;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DefaultEdgeLink;
+import org.onosproject.net.DefaultPath;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.EdgeLink;
+import org.onosproject.net.ElementId;
+import org.onosproject.net.Host;
+import org.onosproject.net.HostId;
+import org.onosproject.net.HostLocation;
+import org.onosproject.net.Link;
+import org.onosproject.net.Path;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.host.HostService;
+import org.onosproject.net.provider.ProviderId;
+import org.onosproject.net.topology.LinkWeight;
+import org.onosproject.net.topology.PathService;
+import org.onosproject.net.topology.Topology;
+import org.onosproject.net.topology.TopologyService;
+import org.slf4j.Logger;
+
+import java.util.List;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.slf4j.LoggerFactory.getLogger;
+import static org.onosproject.security.AppGuard.checkPermission;
+import static org.onosproject.security.AppPermission.Type.*;
+
+
+/**
+ * Provides implementation of a path selection service atop the current
+ * topology and host services.
+ */
+@Component(immediate = true)
+@Service
+public class PathManager implements PathService {
+
+    private static final String ELEMENT_ID_NULL = "Element ID cannot be null";
+
+    private static final ProviderId PID = new ProviderId("core", "org.onosproject.core");
+    private static final PortNumber P0 = PortNumber.portNumber(0);
+
+    private static final EdgeLink NOT_HOST = new NotHost();
+
+    private final Logger log = getLogger(getClass());
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected TopologyService topologyService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected HostService hostService;
+
+    @Activate
+    public void activate() {
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        log.info("Stopped");
+    }
+
+    @Override
+    public Set<Path> getPaths(ElementId src, ElementId dst) {
+        checkPermission(TOPOLOGY_READ);
+
+        return getPaths(src, dst, null);
+    }
+
+    @Override
+    public Set<Path> getPaths(ElementId src, ElementId dst, LinkWeight weight) {
+        checkPermission(TOPOLOGY_READ);
+
+        checkNotNull(src, ELEMENT_ID_NULL);
+        checkNotNull(dst, ELEMENT_ID_NULL);
+
+        // Get the source and destination edge locations
+        EdgeLink srcEdge = getEdgeLink(src, true);
+        EdgeLink dstEdge = getEdgeLink(dst, false);
+
+        // If either edge is null, bail with no paths.
+        if (srcEdge == null || dstEdge == null) {
+            return ImmutableSet.of();
+        }
+
+        DeviceId srcDevice = srcEdge != NOT_HOST ? srcEdge.dst().deviceId() : (DeviceId) src;
+        DeviceId dstDevice = dstEdge != NOT_HOST ? dstEdge.src().deviceId() : (DeviceId) dst;
+
+        // If the source and destination are on the same edge device, there
+        // is just one path, so build it and return it.
+        if (srcDevice.equals(dstDevice)) {
+            return edgeToEdgePaths(srcEdge, dstEdge);
+        }
+
+        // Otherwise get all paths between the source and destination edge
+        // devices.
+        Topology topology = topologyService.currentTopology();
+        Set<Path> paths = weight == null ?
+                topologyService.getPaths(topology, srcDevice, dstDevice) :
+                topologyService.getPaths(topology, srcDevice, dstDevice, weight);
+
+        return edgeToEdgePaths(srcEdge, dstEdge, paths);
+    }
+
+    // Finds the host edge link if the element ID is a host id of an existing
+    // host. Otherwise, if the host does not exist, it returns null and if
+    // the element ID is not a host ID, returns NOT_HOST edge link.
+    private EdgeLink getEdgeLink(ElementId elementId, boolean isIngress) {
+        if (elementId instanceof HostId) {
+            // Resolve the host, return null.
+            Host host = hostService.getHost((HostId) elementId);
+            if (host == null) {
+                return null;
+            }
+            return new DefaultEdgeLink(PID, new ConnectPoint(elementId, P0),
+                                       host.location(), isIngress);
+        }
+        return NOT_HOST;
+    }
+
+    // Produces a set of edge-to-edge paths using the set of infrastructure
+    // paths and the given edge links.
+    private Set<Path> edgeToEdgePaths(EdgeLink srcLink, EdgeLink dstLink) {
+        Set<Path> endToEndPaths = Sets.newHashSetWithExpectedSize(1);
+        endToEndPaths.add(edgeToEdgePath(srcLink, dstLink, null));
+        return endToEndPaths;
+    }
+
+    // Produces a set of edge-to-edge paths using the set of infrastructure
+    // paths and the given edge links.
+    private Set<Path> edgeToEdgePaths(EdgeLink srcLink, EdgeLink dstLink, Set<Path> paths) {
+        Set<Path> endToEndPaths = Sets.newHashSetWithExpectedSize(paths.size());
+        for (Path path : paths) {
+            endToEndPaths.add(edgeToEdgePath(srcLink, dstLink, path));
+        }
+        return endToEndPaths;
+    }
+
+    // Produces a direct edge-to-edge path.
+    private Path edgeToEdgePath(EdgeLink srcLink, EdgeLink dstLink, Path path) {
+        List<Link> links = Lists.newArrayListWithCapacity(2);
+        // Add source and destination edge links only if they are real and
+        // add the infrastructure path only if it is not null.
+        if (srcLink != NOT_HOST) {
+            links.add(srcLink);
+        }
+        if (path != null) {
+            links.addAll(path.links());
+        }
+        if (dstLink != NOT_HOST) {
+            links.add(dstLink);
+        }
+        return new DefaultPath(PID, links, 2);
+    }
+
+    // Special value for edge link to represent that this is really not an
+    // edge link since the src or dst are really an infrastructure device.
+    private static class NotHost extends DefaultEdgeLink implements EdgeLink {
+        NotHost() {
+            super(PID, new ConnectPoint(HostId.NONE, P0),
+                  new HostLocation(DeviceId.NONE, P0, 0L), false);
+        }
+    }
+}