Decouple config and netconf subsystems.

[controller.git] / opendaylight / config / config-persister-impl / src / main / java / org / opendaylight / controller / config / persist / impl / CapabilityStrippingConfigSnapshotHolder.java

diff --git a/opendaylight/config/config-persister-impl/src/main/java/org/opendaylight/controller/config/persist/impl/CapabilityStrippingConfigSnapshotHolder.java b/opendaylight/config/config-persister-impl/src/main/java/org/opendaylight/controller/config/persist/impl/CapabilityStrippingConfigSnapshotHolder.java
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+++ b/opendaylight/config/config-persister-impl/src/main/java/org/opendaylight/controller/config/persist/impl/CapabilityStrippingConfigSnapshotHolder.java
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+/*
+ * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.controller.config.persist.impl;
+
+import com.google.common.annotations.VisibleForTesting;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.SortedSet;
+import java.util.TreeSet;
+import org.opendaylight.controller.config.persist.api.ConfigSnapshotHolder;
+import org.opendaylight.controller.config.util.xml.XmlElement;
+import org.opendaylight.controller.config.util.xml.XmlUtil;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.w3c.dom.Attr;
+import org.w3c.dom.Element;
+
+/**
+ * Inspects snapshot xml to be stored, remove all capabilities that are not referenced by it.
+ * Useful when persisting current configuration.
+ */
+public class CapabilityStrippingConfigSnapshotHolder implements ConfigSnapshotHolder {
+    private static final Logger LOG = LoggerFactory.getLogger(CapabilityStrippingConfigSnapshotHolder.class);
+
+    private final String configSnapshot;
+    private final StripCapabilitiesResult stripCapabilitiesResult;
+
+    public CapabilityStrippingConfigSnapshotHolder(Element snapshot, Set<String> capabilities) {
+        final XmlElement configElement = XmlElement.fromDomElement(snapshot);
+        configSnapshot = XmlUtil.toString(configElement.getDomElement());
+        stripCapabilitiesResult = stripCapabilities(configElement, capabilities);
+    }
+
+    private static class StripCapabilitiesResult {
+        private final SortedSet<String> requiredCapabilities, obsoleteCapabilities;
+
+        private StripCapabilitiesResult(SortedSet<String> requiredCapabilities, SortedSet<String> obsoleteCapabilities) {
+            this.requiredCapabilities = Collections.unmodifiableSortedSet(requiredCapabilities);
+            this.obsoleteCapabilities = Collections.unmodifiableSortedSet(obsoleteCapabilities);
+        }
+    }
+
+
+    @VisibleForTesting
+    static StripCapabilitiesResult stripCapabilities(XmlElement configElement, Set<String> allCapabilitiesFromHello) {
+        // collect all namespaces
+        Set<String> foundNamespacesInXML = getNamespaces(configElement);
+        LOG.trace("All capabilities {}\nFound namespaces in XML {}", allCapabilitiesFromHello, foundNamespacesInXML);
+        // required are referenced both in xml and hello
+        SortedSet<String> requiredCapabilities = new TreeSet<>();
+        // can be removed
+        SortedSet<String> obsoleteCapabilities = new TreeSet<>();
+        for (String capability : allCapabilitiesFromHello) {
+            String namespace = capability.replaceAll("\\?.*","");
+            if (foundNamespacesInXML.contains(namespace)) {
+                requiredCapabilities.add(capability);
+            } else {
+                obsoleteCapabilities.add(capability);
+            }
+        }
+
+        LOG.trace("Required capabilities {}, \nObsolete capabilities {}",
+                requiredCapabilities, obsoleteCapabilities);
+
+        return new StripCapabilitiesResult(requiredCapabilities, obsoleteCapabilities);
+    }
+
+    static Set<String> getNamespaces(XmlElement element){
+        Set<String> result = new HashSet<>();
+        for (Entry<String,Attr> attribute : element.getAttributes().entrySet()) {
+            if  (attribute.getKey().startsWith("xmlns")){
+                result.add(attribute.getValue().getValue());
+            }
+        }
+        for(XmlElement child: element.getChildElements()) {
+            result.addAll(getNamespaces(child));
+        }
+        return result;
+    }
+
+    @Override
+    public SortedSet<String> getCapabilities() {
+        return stripCapabilitiesResult.requiredCapabilities;
+    }
+
+    @VisibleForTesting
+    Set<String> getObsoleteCapabilities(){
+        return stripCapabilitiesResult.obsoleteCapabilities;
+    }
+
+    @Override
+    public String getConfigSnapshot() {
+        return configSnapshot;
+    }
+}