Initial sketch of YANG runtime API.
Change-Id: I166f877e484284aa7fa75b33d539f74d9835883b
diff --git a/runtime/src/main/java/org/onosproject/yang/ContainerDataNode.java b/runtime/src/main/java/org/onosproject/yang/ContainerDataNode.java
new file mode 100644
index 0000000..16d8e42
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+++ b/runtime/src/main/java/org/onosproject/yang/ContainerDataNode.java
@@ -0,0 +1,32 @@
+/*
+ * Copyright 2016-present 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.yang;
+
+import java.util.List;
+
+/**
+ * Representation of a container data node capable of containing children nodes.
+ */
+public interface ContainerDataNode extends DataNode {
+
+ // List of children
+ List<DataNode> children();
+
+ // Child with specific identifier
+ DataNode child(String identifier); // TODO: Use NodeIdentifier instead of String
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/DataNode.java b/runtime/src/main/java/org/onosproject/yang/DataNode.java
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index 0000000..97ce1c6
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+++ b/runtime/src/main/java/org/onosproject/yang/DataNode.java
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+/*
+ * Copyright 2016-present 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.yang;
+
+/**
+ * Representation of a configuration data node capable of either carrying data
+ * or conveying the configuration tree structure.
+ */
+public interface DataNode {
+
+ // TODO: specify generic nature of holding data and/or tree structure
+ // TODO: determine whether there should be subclasses for leaf, container, etc.
+ // identifier
+ // type
+ // no parent!
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/LeafDataNode.java b/runtime/src/main/java/org/onosproject/yang/LeafDataNode.java
new file mode 100644
index 0000000..69b1bb0
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+++ b/runtime/src/main/java/org/onosproject/yang/LeafDataNode.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2016-present 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.yang;
+
+/**
+ * Representation of a leaf data node capable of holding a value.
+ */
+public interface LeafDataNode extends DataNode {
+
+ // String, Number or Boolean primitive values
+ Object value();
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/YangModel.java b/runtime/src/main/java/org/onosproject/yang/YangModel.java
new file mode 100644
index 0000000..dbfcfee
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/YangModel.java
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2016-present 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.yang;
+
+import java.io.InputStream;
+import java.util.Set;
+
+/**
+ * Representation of a compiled YANG model.
+ */
+public interface YangModel {
+
+ // name
+ // schema meta-data!!!
+
+ // set of source yang files (names & streams)
+ Set<String> getYangFiles();
+
+ InputStream getYangSource(String name);
+
+ // set of generated model classes
+ Set<String> getJavaModelClasses();
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/package-info.java b/runtime/src/main/java/org/onosproject/yang/package-info.java
new file mode 100644
index 0000000..e1a76c3
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+++ b/runtime/src/main/java/org/onosproject/yang/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2016-present 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.
+ */
+
+/**
+ * Basic constructs for compiling and working with YANG models.
+ */
+package org.onosproject.yang;
\ No newline at end of file
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/DataFormat.java b/runtime/src/main/java/org/onosproject/yang/runtime/DataFormat.java
new file mode 100644
index 0000000..3902362
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/runtime/DataFormat.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+/**
+ * Abstraction of configuration data-format descriptor.
+ */
+public interface DataFormat {
+
+ // TODO: should this be an enum instead with choices fixed at compile-time?
+ // name, e.g. "XML", "JSON"
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/YangModelRegistry.java b/runtime/src/main/java/org/onosproject/yang/runtime/YangModelRegistry.java
new file mode 100644
index 0000000..6048c11
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/runtime/YangModelRegistry.java
@@ -0,0 +1,49 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+import org.onosproject.yang.YangModel;
+
+import java.util.Set;
+
+/**
+ * Registry of YANG models known to YANG runtime.
+ */
+public interface YangModelRegistry {
+
+ /**
+ * Registers a new model.
+ *
+ * @param model model to be registered
+ */
+ void registerModel(YangModel model);
+
+ /**
+ * Unregisters the specified model.
+ *
+ * @param model model to be unregistered
+ */
+ void unregisterModel(YangModel model);
+
+ /**
+ * Returns collection of all registered models.
+ *
+ * @return collection of models
+ */
+ Set<YangModel> getModels();
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/YangRuntimeService.java b/runtime/src/main/java/org/onosproject/yang/runtime/YangRuntimeService.java
new file mode 100644
index 0000000..6c69507
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/runtime/YangRuntimeService.java
@@ -0,0 +1,51 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+import org.onosproject.yang.DataNode;
+
+import java.io.InputStream;
+
+/**
+ * Service for encoding and decoding between internal and external model
+ * representations.
+ */
+public interface YangRuntimeService {
+
+ /**
+ * Decodes the external representation of a configuration model from the
+ * specified input stream and into an in-memory representation.
+ *
+ * @param external input stream carrying external representation of
+ * configuration data
+ * @param format data format of the provided external representation
+ * @return in-memory representation of configuration data
+ */
+ DataNode decode(InputStream external, DataFormat format);
+
+ /**
+ * Encodes the internal in-memory representation of a configuration model
+ * to an external representation consumable from the resulting input stream.
+ *
+ * @param internal in-memory representation of configuration data
+ * @param format expected data format of the external representation
+ * @return input stream carrying external representation of
+ * configuration data
+ */
+ InputStream encode(DataNode internal, DataFormat format);
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializer.java b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializer.java
new file mode 100644
index 0000000..0ce4308
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializer.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+import org.onosproject.yang.DataNode;
+
+import java.io.InputStream;
+
+/**
+ * Abstraction of entity capable of encoding and decoding arbitrary
+ * {@link DataNode} structures, which are in-memory representations of
+ * YANG models, to and from various external representations, e.g. XML, JSON.
+ * <p>
+ * This interface is not intended for use by applications, but rather only
+ * by the YANG runtime implementation.
+ * </p>
+ */
+public interface YangSerializer {
+
+ /**
+ * Returns the data format supported by this serializer.
+ *
+ * @return supported data format
+ */
+ DataFormat supportsFormat();
+
+ /**
+ * Decodes the external representation of a configuration model from the
+ * specified input stream and into an in-memory representation.
+ *
+ * @param external input stream carrying external representation of
+ * configuration data
+ * @param context serialization context containing information required
+ * for the serializer, e.g. access to model schemas
+ * @return in-memory representation of configuration data
+ */
+ DataNode decode(InputStream external, YangSerializerContext context);
+
+ /**
+ * Encodes the internal in-memory representation of a configuration model
+ * to an external representation consumable from the resulting input stream.
+ *
+ * @param internal in-memory representation of configuration data
+ * @param context serialization context containing information required
+ * for the serializer, e.g. access to model schemas
+ * @return input stream carrying external representation of
+ * configuration data
+ */
+ InputStream encode(DataNode internal, YangSerializerContext context);
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerContext.java b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerContext.java
new file mode 100644
index 0000000..e2b2cbf
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+++ b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerContext.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+/**
+ * Representation of a context for encoding and decoding YANG models via
+ * serializers.
+ */
+public interface YangSerializerContext {
+
+ // any required facilitites for serialization go here
+ //
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerRegistry.java b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerRegistry.java
new file mode 100644
index 0000000..13aae92
--- /dev/null
+++ b/runtime/src/main/java/org/onosproject/yang/runtime/YangSerializerRegistry.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2016-present 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.yang.runtime;
+
+import java.util.Set;
+
+/**
+ * Registry of YANG serializers available as part of YANG runtime.
+ */
+public interface YangSerializerRegistry {
+
+ /**
+ * Registers a new serializer.
+ *
+ * @param serializer serializer to be registered
+ */
+ void registerSerializer(YangSerializer serializer);
+
+ /**
+ * Unregisters the specified serializer.
+ *
+ * @param serializer serializer to be unregistered
+ */
+ void unregisterSerializer(YangSerializer serializer);
+
+ /**
+ * Returns collection of all registered serializers.
+ *
+ * @return collection of serializers
+ */
+ Set<YangSerializer> getSerializers();
+
+}
diff --git a/runtime/src/main/java/org/onosproject/yang/runtime/package-info.java b/runtime/src/main/java/org/onosproject/yang/runtime/package-info.java
new file mode 100644
index 0000000..6b8a685
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+++ b/runtime/src/main/java/org/onosproject/yang/runtime/package-info.java
@@ -0,0 +1,20 @@
+/*
+ * Copyright 2016-present 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.
+ */
+
+/**
+ * Set of facilities for processing and working with compiled YANG models.
+ */
+package org.onosproject.yang.runtime;
\ No newline at end of file