Add path intent compiler that generates flow objective intents
Change-Id: I11bee398d927f0e3f32b7cf81d98cfe5816db477
diff --git a/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/PathCompiler.java b/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/PathCompiler.java
new file mode 100644
index 0000000..7514250
--- /dev/null
+++ b/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/PathCompiler.java
@@ -0,0 +1,274 @@
+/*
+ * Copyright 2016 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.intent.impl.compiler;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.onlab.packet.VlanId;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Link;
+import org.onosproject.net.LinkKey;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flow.criteria.Criterion;
+import org.onosproject.net.flow.criteria.VlanIdCriterion;
+import org.onosproject.net.flow.instructions.L2ModificationInstruction;
+import org.onosproject.net.intent.PathIntent;
+import org.onosproject.net.intent.constraint.EncapsulationConstraint;
+import org.onosproject.net.intent.impl.IntentCompilationException;
+import org.onosproject.net.newresource.Resource;
+import org.onosproject.net.newresource.ResourceService;
+import org.onosproject.net.newresource.Resources;
+import org.slf4j.Logger;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Sets;
+
+import static org.onosproject.net.LinkKey.linkKey;
+
+/**
+ * Shared APIs and implementations for path compilers.
+ */
+
+public class PathCompiler<T> {
+
+ /**
+ * Defines methods used to create objects representing flows.
+ */
+ public interface PathCompilerCreateFlow<T> {
+
+ void createFlow(TrafficSelector originalSelector,
+ TrafficTreatment originalTreatment,
+ ConnectPoint ingress, ConnectPoint egress,
+ int priority,
+ boolean applyTreatment,
+ List<T> flows,
+ List<DeviceId> devices);
+
+ Logger log();
+
+ ResourceService resourceService();
+ }
+
+ private boolean isLast(List<Link> links, int i) {
+ return i == links.size() - 2;
+ }
+
+ private Map<LinkKey, VlanId> assignVlanId(PathCompilerCreateFlow creator, PathIntent intent) {
+ Set<LinkKey> linkRequest =
+ Sets.newHashSetWithExpectedSize(intent.path()
+ .links().size() - 2);
+ for (int i = 1; i <= intent.path().links().size() - 2; i++) {
+ LinkKey link = linkKey(intent.path().links().get(i));
+ linkRequest.add(link);
+ // add the inverse link. I want that the VLANID is reserved both for
+ // the direct and inverse link
+ linkRequest.add(linkKey(link.dst(), link.src()));
+ }
+
+ Map<LinkKey, VlanId> vlanIds = findVlanIds(creator, linkRequest);
+ if (vlanIds.isEmpty()) {
+ creator.log().warn("No VLAN IDs available");
+ return Collections.emptyMap();
+ }
+
+ //same VLANID is used for both directions
+ Set<Resource> resources = vlanIds.entrySet().stream()
+ .flatMap(x -> Stream.of(
+ Resources.discrete(x.getKey().src().deviceId(), x.getKey().src().port(), x.getValue())
+ .resource(),
+ Resources.discrete(x.getKey().dst().deviceId(), x.getKey().dst().port(), x.getValue())
+ .resource()
+ ))
+ .collect(Collectors.toSet());
+ List<org.onosproject.net.newresource.ResourceAllocation> allocations =
+ creator.resourceService().allocate(intent.id(), ImmutableList.copyOf(resources));
+ if (allocations.isEmpty()) {
+ Collections.emptyMap();
+ }
+
+ return vlanIds;
+ }
+
+ private Map<LinkKey, VlanId> findVlanIds(PathCompilerCreateFlow creator, Set<LinkKey> links) {
+ Map<LinkKey, VlanId> vlanIds = new HashMap<>();
+ for (LinkKey link : links) {
+ Set<VlanId> forward = findVlanId(creator, link.src());
+ Set<VlanId> backward = findVlanId(creator, link.dst());
+ Set<VlanId> common = Sets.intersection(forward, backward);
+ if (common.isEmpty()) {
+ continue;
+ }
+ vlanIds.put(link, common.iterator().next());
+ }
+ return vlanIds;
+ }
+
+ private Set<VlanId> findVlanId(PathCompilerCreateFlow creator, ConnectPoint cp) {
+ return creator.resourceService().getAvailableResourceValues(
+ Resources.discrete(cp.deviceId(), cp.port()).id(),
+ VlanId.class);
+ }
+
+ private void manageVlanEncap(PathCompilerCreateFlow<T> creator, List<T> flows,
+ List<DeviceId> devices,
+ PathIntent intent) {
+ Map<LinkKey, VlanId> vlanIds = assignVlanId(creator, intent);
+
+ Iterator<Link> links = intent.path().links().iterator();
+ Link srcLink = links.next();
+
+ Link link = links.next();
+
+ // Ingress traffic
+ VlanId vlanId = vlanIds.get(linkKey(link));
+ if (vlanId == null) {
+ throw new IntentCompilationException("No available VLAN ID for " + link);
+ }
+ VlanId prevVlanId = vlanId;
+
+ Optional<VlanIdCriterion> vlanCriterion = intent.selector().criteria()
+ .stream().filter(criterion -> criterion.type() == Criterion.Type.VLAN_VID)
+ .map(criterion -> (VlanIdCriterion) criterion)
+ .findAny();
+
+ //Push VLAN if selector does not include VLAN
+ TrafficTreatment.Builder treatBuilder = DefaultTrafficTreatment.builder();
+ if (!vlanCriterion.isPresent()) {
+ treatBuilder.pushVlan();
+ }
+ //Tag the traffic with the new encapsulation VLAN
+ treatBuilder.setVlanId(vlanId);
+ creator.createFlow(intent.selector(), treatBuilder.build(),
+ srcLink.dst(), link.src(), intent.priority(), true,
+ flows, devices);
+
+ ConnectPoint prev = link.dst();
+
+ while (links.hasNext()) {
+
+ link = links.next();
+
+ if (links.hasNext()) {
+ // Transit traffic
+ VlanId egressVlanId = vlanIds.get(linkKey(link));
+ if (egressVlanId == null) {
+ throw new IntentCompilationException("No available VLAN ID for " + link);
+ }
+ prevVlanId = egressVlanId;
+
+ TrafficSelector transitSelector = DefaultTrafficSelector.builder()
+ .matchInPort(prev.port())
+ .matchVlanId(prevVlanId).build();
+
+ TrafficTreatment.Builder transitTreat = DefaultTrafficTreatment.builder();
+
+ // Set the new vlanId only if the previous one is different
+ if (!prevVlanId.equals(egressVlanId)) {
+ transitTreat.setVlanId(egressVlanId);
+ }
+ creator.createFlow(transitSelector,
+ transitTreat.build(), prev, link.src(),
+ intent.priority(), true, flows, devices);
+ prev = link.dst();
+ } else {
+ // Egress traffic
+ TrafficSelector egressSelector = DefaultTrafficSelector.builder()
+ .matchInPort(prev.port())
+ .matchVlanId(prevVlanId).build();
+ TrafficTreatment.Builder egressTreat = DefaultTrafficTreatment.builder(intent.treatment());
+
+ Optional<L2ModificationInstruction.ModVlanIdInstruction> modVlanIdInstruction = intent.treatment()
+ .allInstructions().stream().filter(
+ instruction -> instruction instanceof L2ModificationInstruction.ModVlanIdInstruction)
+ .map(x -> (L2ModificationInstruction.ModVlanIdInstruction) x).findAny();
+
+ Optional<L2ModificationInstruction.PopVlanInstruction> popVlanInstruction = intent.treatment()
+ .allInstructions().stream().filter(
+ instruction -> instruction instanceof L2ModificationInstruction.PopVlanInstruction)
+ .map(x -> (L2ModificationInstruction.PopVlanInstruction) x).findAny();
+
+ if (!modVlanIdInstruction.isPresent() && !popVlanInstruction.isPresent()) {
+ if (vlanCriterion.isPresent()) {
+ egressTreat.setVlanId(vlanCriterion.get().vlanId());
+ } else {
+ egressTreat.popVlan();
+ }
+ }
+
+ creator.createFlow(egressSelector,
+ egressTreat.build(), prev, link.src(),
+ intent.priority(), true, flows, devices);
+ }
+ }
+ }
+
+ /**
+ * Compiles an intent down to flows.
+ *
+ * @param creator how to create the flows
+ * @param intent intent to process
+ * @param flows list of generated flows
+ * @param devices list of devices that correspond to the flows
+ */
+ public void compile(PathCompilerCreateFlow<T> creator,
+ PathIntent intent,
+ List<T> flows,
+ List<DeviceId> devices) {
+ // Note: right now recompile is not considered
+ // TODO: implement recompile behavior
+
+ List<Link> links = intent.path().links();
+
+ Optional<EncapsulationConstraint> encapConstraint = intent.constraints().stream()
+ .filter(constraint -> constraint instanceof EncapsulationConstraint)
+ .map(x -> (EncapsulationConstraint) x).findAny();
+ //if no encapsulation or is involved only a single switch use the default behaviour
+ if (!encapConstraint.isPresent() || links.size() == 1) {
+ for (int i = 0; i < links.size() - 1; i++) {
+ ConnectPoint ingress = links.get(i).dst();
+ ConnectPoint egress = links.get(i + 1).src();
+ creator.createFlow(intent.selector(), intent.treatment(),
+ ingress, egress, intent.priority(),
+ isLast(links, i), flows, devices);
+ }
+ }
+
+ encapConstraint.map(EncapsulationConstraint::encapType)
+ .map(type -> {
+ switch (type) {
+ case VLAN:
+ manageVlanEncap(creator, flows, devices, intent);
+ // TODO: implement MPLS case here
+ default:
+ // Nothing to do
+ }
+ return 0;
+ });
+ }
+
+}