/*
* Copyright (c) 2014 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.yangtools.yang.data.codec.gson;
import static org.opendaylight.yangtools.yang.data.codec.gson.JsonParserStream.ANYXML_ARRAY_ELEMENT_ID;
import static org.w3c.dom.Node.ELEMENT_NODE;
import static org.w3c.dom.Node.TEXT_NODE;
import com.google.common.base.Preconditions;
import com.google.common.base.Throwables;
import com.google.gson.stream.JsonWriter;
import java.io.IOException;
import java.net.URI;
import java.util.regex.Pattern;
import javax.annotation.RegEx;
import javax.xml.transform.dom.DOMSource;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.AugmentationIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
import org.opendaylight.yangtools.yang.data.impl.codec.SchemaTracker;
import org.opendaylight.yangtools.yang.model.api.AnyXmlSchemaNode;
import org.opendaylight.yangtools.yang.model.api.LeafListSchemaNode;
import org.opendaylight.yangtools.yang.model.api.LeafSchemaNode;
import org.opendaylight.yangtools.yang.model.api.SchemaNode;
import org.opendaylight.yangtools.yang.model.api.SchemaPath;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* This implementation will create JSON output as output stream.
*
* Values of leaf and leaf-list are NOT translated according to codecs.
*
*/
public final class JSONNormalizedNodeStreamWriter implements NormalizedNodeStreamWriter {
/**
* RFC6020 deviation: we are not required to emit empty containers unless they
* are marked as 'presence'.
*/
private static final boolean DEFAULT_EMIT_EMPTY_CONTAINERS = true;
@RegEx
private static final String NUMBER_STRING = "-?\\d+(\\.\\d+)?";
private static final Pattern NUMBER_PATTERN = Pattern.compile(NUMBER_STRING);
@RegEx
private static final String NOT_DECIMAL_NUMBER_STRING = "-?\\d+";
private static final Pattern NOT_DECIMAL_NUMBER_PATTERN = Pattern.compile(NOT_DECIMAL_NUMBER_STRING);
private final SchemaTracker tracker;
private final JSONCodecFactory codecs;
private final JsonWriter writer;
private JSONStreamWriterContext context;
private JSONNormalizedNodeStreamWriter(final JSONCodecFactory codecFactory, final SchemaPath path, final JsonWriter JsonWriter, final JSONStreamWriterRootContext rootContext) {
this.writer = Preconditions.checkNotNull(JsonWriter);
this.codecs = Preconditions.checkNotNull(codecFactory);
this.tracker = SchemaTracker.create(codecFactory.getSchemaContext(), path);
this.context = Preconditions.checkNotNull(rootContext);
}
/**
* Create a new stream writer, which writes to the specified output stream.
*
* The codec factory can be reused between multiple writers.
*
* Returned writer is exclusive user of JsonWriter, which means it will start
* top-level JSON element and ends it.
*
* This instance of writer can be used only to emit one top level element,
* otherwise it will produce incorrect JSON.
*
* @param codecFactory JSON codec factory
* @param path Schema Path
* @param initialNs Initial namespace
* @param jsonWriter JsonWriter
* @return A stream writer instance
*/
public static NormalizedNodeStreamWriter createExclusiveWriter(final JSONCodecFactory codecFactory, final SchemaPath path, final URI initialNs, final JsonWriter jsonWriter) {
return new JSONNormalizedNodeStreamWriter(codecFactory, path, jsonWriter, new JSONStreamWriterExclusiveRootContext(initialNs));
}
/**
* Create a new stream writer, which writes to the specified output stream.
*
* The codec factory can be reused between multiple writers.
*
* Returned writer can be used emit multiple top level element,
* but does not start / close parent JSON object, which must be done
* by user providing {@code jsonWriter} instance in order for
* JSON to be valid.
*
* @param codecFactory JSON codec factory
* @param path Schema Path
* @param initialNs Initial namespace
* @param jsonWriter JsonWriter
* @return A stream writer instance
*/
public static NormalizedNodeStreamWriter createNestedWriter(final JSONCodecFactory codecFactory, final SchemaPath path, final URI initialNs, final JsonWriter jsonWriter) {
return new JSONNormalizedNodeStreamWriter(codecFactory, path, jsonWriter, new JSONStreamWriterSharedRootContext(initialNs));
}
@Override
public void leafNode(final NodeIdentifier name, final Object value) throws IOException {
final LeafSchemaNode schema = tracker.leafNode(name);
final JSONCodec<?> codec = codecs.codecFor(schema);
context.emittingChild(codecs.getSchemaContext(), writer);
context.writeChildJsonIdentifier(codecs.getSchemaContext(), writer, name.getNodeType());
writeValue(value, codec);
}
@Override
public void startLeafSet(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startLeafSet(name);
context = new JSONStreamWriterListContext(context, name);
}
@Override
public void leafSetEntryNode(final QName name, final Object value) throws IOException {
final LeafListSchemaNode schema = tracker.leafSetEntryNode(name);
final JSONCodec<?> codec = codecs.codecFor(schema);
context.emittingChild(codecs.getSchemaContext(), writer);
writeValue(value, codec);
}
@Override
public void startOrderedLeafSet(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startLeafSet(name);
context = new JSONStreamWriterListContext(context, name);
}
/*
* Warning suppressed due to static final constant which triggers a warning
* for the call to schema.isPresenceContainer().
*/
@SuppressWarnings("unused")
@Override
public void startContainerNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
final SchemaNode schema = tracker.startContainerNode(name);
// FIXME this code ignores presence for containers
// but datastore does as well and it needs be fixed first (2399)
context = new JSONStreamWriterNamedObjectContext(context, name, DEFAULT_EMIT_EMPTY_CONTAINERS);
}
@Override
public void startUnkeyedList(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startList(name);
context = new JSONStreamWriterListContext(context, name);
}
@Override
public void startUnkeyedListItem(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startListItem(name);
context = new JSONStreamWriterObjectContext(context, name, DEFAULT_EMIT_EMPTY_CONTAINERS);
}
@Override
public void startMapNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startList(name);
context = new JSONStreamWriterListContext(context, name);
}
@Override
public void startMapEntryNode(final NodeIdentifierWithPredicates identifier, final int childSizeHint)
throws IOException {
tracker.startListItem(identifier);
context = new JSONStreamWriterObjectContext(context, identifier, DEFAULT_EMIT_EMPTY_CONTAINERS);
}
@Override
public void startOrderedMapNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startList(name);
context = new JSONStreamWriterListContext(context, name);
}
@Override
public void startChoiceNode(final NodeIdentifier name, final int childSizeHint) {
tracker.startChoiceNode(name);
context = new JSONStreamWriterInvisibleContext(context);
}
@Override
public void startAugmentationNode(final AugmentationIdentifier identifier) {
tracker.startAugmentationNode(identifier);
context = new JSONStreamWriterInvisibleContext(context);
}
@Override
public void anyxmlNode(final NodeIdentifier name, final Object value) throws IOException {
@SuppressWarnings("unused")
final AnyXmlSchemaNode schema = tracker.anyxmlNode(name);
// FIXME: should have a codec based on this :)
context.emittingChild(codecs.getSchemaContext(), writer);
context.writeChildJsonIdentifier(codecs.getSchemaContext(), writer, name.getNodeType());
writeAnyXmlValue((DOMSource) value);
}
@Override
public void startYangModeledAnyXmlNode(final NodeIdentifier name, final int childSizeHint) throws IOException {
tracker.startYangModeledAnyXmlNode(name);
context = new JSONStreamWriterNamedObjectContext(context, name, true);
}
@Override
public void endNode() throws IOException {
tracker.endNode();
context = context.endNode(codecs.getSchemaContext(), writer);
if (context instanceof JSONStreamWriterRootContext) {
context.emitEnd(writer);
}
}
@SuppressWarnings("unchecked")
private void writeValue(final Object value, final JSONCodec<?> codec)
throws IOException {
try {
((JSONCodec<Object>) codec).writeValue(writer, value);
} catch (IOException e) {
throw e;
} catch (Exception e) {
Throwables.propagateIfPossible(e);
throw new RuntimeException(e);
}
}
private void writeAnyXmlValue(final DOMSource anyXmlValue) throws IOException {
final Node documentNode = anyXmlValue.getNode();
final Node firstChild = documentNode.getFirstChild();
if (ELEMENT_NODE == firstChild.getNodeType() && !ANYXML_ARRAY_ELEMENT_ID.equals(firstChild.getNodeName())) {
writer.beginObject();
traverseAnyXmlValue(documentNode);
writer.endObject();
} else {
traverseAnyXmlValue(documentNode);
}
}
private void traverseAnyXmlValue(final Node node) throws IOException {
final NodeList children = node.getChildNodes();
boolean inArray = false;
for (int i = 0, length = children.getLength(); i < length; i++) {
final Node childNode = children.item(i);
boolean inObject = false;
if (ELEMENT_NODE == childNode.getNodeType()) {
final Node firstChild = childNode.getFirstChild();
// beginning of an array
if (ANYXML_ARRAY_ELEMENT_ID.equals(childNode.getNodeName()) && !inArray) {
writer.beginArray();
inArray = true;
// object at the beginning of the array
if (isJsonObjectInArray(childNode, firstChild)) {
writer.beginObject();
inObject = true;
}
// object in the array
} else if (isJsonObjectInArray(childNode, firstChild)) {
writer.beginObject();
inObject = true;
// object
} else if (isJsonObject(firstChild)) {
writer.name(childNode.getNodeName());
writer.beginObject();
inObject = true;
// name
} else if (!inArray){
writer.name(childNode.getNodeName());
}
}
// text value, i.e. a number, string, boolean or null
if (TEXT_NODE == childNode.getNodeType()) {
final String childNodeText = childNode.getNodeValue();
if (NUMBER_PATTERN.matcher(childNodeText).matches()) {
writer.value(parseNumber(childNodeText));
} else if ("true".equals(childNodeText) || "false".equals(childNodeText)) {
writer.value(Boolean.parseBoolean(childNodeText));
} else if ("null".equals(childNodeText)) {
writer.nullValue();
} else {
writer.value(childNodeText);
}
return;
}
traverseAnyXmlValue(childNode);
if (inObject) {
writer.endObject();
}
}
if (inArray) {
writer.endArray();
}
}
// json numbers are 64 bit wide floating point numbers - in java terms it is either long or double
private static Number parseNumber(final String numberText) {
if (NOT_DECIMAL_NUMBER_PATTERN.matcher(numberText).matches()) {
return Long.valueOf(numberText);
}
return Double.valueOf(numberText);
}
private static boolean isJsonObject(final Node firstChild) {
return !ANYXML_ARRAY_ELEMENT_ID.equals(firstChild.getNodeName()) && TEXT_NODE != firstChild.getNodeType();
}
private static boolean isJsonObjectInArray(final Node node, final Node firstChild) {
return ANYXML_ARRAY_ELEMENT_ID.equals(node.getNodeName())
&& !ANYXML_ARRAY_ELEMENT_ID.equals(firstChild.getNodeName())
&& TEXT_NODE != firstChild.getNodeType();
}
@Override
public void flush() throws IOException {
writer.flush();
}
@Override
public void close() throws IOException {
flush();
writer.close();
}
}