Sketching out device driver subsystem to allow extensible device management functions to be made available to applications.
Revising some implementations and adding tests.
Removing fingerprint and extension concept for now.
Change-Id: Id50faf29e4590b08e0c2b385ae8d4bb0c453f37e
diff --git a/core/api/src/main/java/org/onosproject/net/driver/XmlDriverLoader.java b/core/api/src/main/java/org/onosproject/net/driver/XmlDriverLoader.java
new file mode 100644
index 0000000..c3bb7ac
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/driver/XmlDriverLoader.java
@@ -0,0 +1,154 @@
+/*
+ * Copyright 2015 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.driver;
+
+import com.google.common.collect.ImmutableMap;
+import org.apache.commons.configuration.ConfigurationException;
+import org.apache.commons.configuration.HierarchicalConfiguration;
+import org.apache.commons.configuration.XMLConfiguration;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Map;
+
+/**
+ * Utility capable of reading driver configuration XML resources and producing
+ * a device driver provider as a result.
+ * <p>
+ * The drivers stream structure is as follows:
+ * </p>
+ * <pre>
+ * <drivers>
+ * <driver name=“...” [manufacturer="..." hwVersion="..." swVersion="..."]>
+ * <behaviour api="..." impl="..."/>
+ * ...
+ * [<property name=“key”>value</key>]
+ * ...
+ * </driver>
+ * ...
+ * </drivers>
+ * </pre>
+ */
+public class XmlDriverLoader {
+
+ private static final String DRIVERS = "drivers";
+ private static final String DRIVER = "driver";
+
+ private static final String BEHAVIOUR = "behaviour";
+ private static final String PROPERTY = "property";
+
+ private static final String NAME = "[@name]";
+ private static final String MFG = "[@manufacturer]";
+ private static final String HW = "[@hwVersion]";
+ private static final String SW = "[@swVersion]";
+ private static final String API = "[@api]";
+ private static final String IMPL = "[@impl]";
+
+ private final ClassLoader classLoader;
+
+ /**
+ * Creates a new driver loader capable of loading drivers from the supplied
+ * class loader.
+ *
+ * @param classLoader class loader to use
+ */
+ public XmlDriverLoader(ClassLoader classLoader) {
+ this.classLoader = classLoader;
+ }
+
+ /**
+ * Loads the specified drivers resource as an XML stream and parses it to
+ * produce a ready-to-register driver provider.
+ *
+ * @param driversStream stream containing the drivers definitions
+ * @return driver provider
+ * @throws java.io.IOException if issues are encountered reading the stream
+ * or parsing the driver definitions within
+ */
+ public DefaultDriverProvider loadDrivers(InputStream driversStream) throws IOException {
+ try {
+ XMLConfiguration cfg = new XMLConfiguration();
+ cfg.setRootElementName(DRIVERS);
+ cfg.setAttributeSplittingDisabled(true);
+
+ cfg.load(driversStream);
+ return loadDrivers(cfg);
+ } catch (ConfigurationException e) {
+ throw new IOException("Unable to load drivers", e);
+ }
+ }
+
+ /**
+ * Loads a driver provider from the supplied hierarchical configuration.
+ *
+ * @param driversCfg hierarchical configuration containing the drivers definitions
+ * @return driver provider
+ */
+ public DefaultDriverProvider loadDrivers(HierarchicalConfiguration driversCfg) {
+ DefaultDriverProvider provider = new DefaultDriverProvider();
+ for (HierarchicalConfiguration cfg : driversCfg.configurationsAt(DRIVER)) {
+ provider.addDriver(loadDriver(cfg));
+ }
+ return provider;
+ }
+
+ /**
+ * Loads a driver from the supplied hierarchical configuration.
+ *
+ * @param driverCfg hierarchical configuration containing the driver definition
+ * @return driver
+ */
+ public DefaultDriver loadDriver(HierarchicalConfiguration driverCfg) {
+ String name = driverCfg.getString(NAME);
+ String manufacturer = driverCfg.getString(MFG, "");
+ String hwVersion = driverCfg.getString(HW, "");
+ String swVersion = driverCfg.getString(SW, "");
+
+ return new DefaultDriver(name, manufacturer, hwVersion, swVersion,
+ parseBehaviours(driverCfg),
+ parseProperties(driverCfg));
+ }
+
+ // Parses the behaviours section.
+ private Map<Class<? extends Behaviour>, Class<? extends Behaviour>>
+ parseBehaviours(HierarchicalConfiguration driverCfg) {
+ ImmutableMap.Builder<Class<? extends Behaviour>,
+ Class<? extends Behaviour>> behaviours = ImmutableMap.builder();
+ for (HierarchicalConfiguration b : driverCfg.configurationsAt(BEHAVIOUR)) {
+ behaviours.put(getClass(b.getString(API)), getClass(b.getString(IMPL)));
+ }
+ return behaviours.build();
+ }
+
+ // Parses the properties section.
+ private Map<String, String> parseProperties(HierarchicalConfiguration driverCfg) {
+ ImmutableMap.Builder<String, String> properties = ImmutableMap.builder();
+ for (HierarchicalConfiguration b : driverCfg.configurationsAt(PROPERTY)) {
+ properties.put(b.getString(NAME), (String) b.getRootNode().getValue());
+ }
+ return properties.build();
+ }
+
+ @SuppressWarnings("unchecked")
+ private Class<? extends Behaviour> getClass(String className) {
+ try {
+ return (Class<? extends Behaviour>) classLoader.loadClass(className);
+ } catch (ClassNotFoundException e) {
+ throw new IllegalArgumentException("Unable to load class " + className, e);
+ }
+ }
+
+}