/**
* Copyright Microsoft Corporation
*
* 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 com.microsoft.azure.storage.table;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.Date;
import java.util.HashMap;
import java.util.Map.Entry;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonToken;
import com.microsoft.azure.storage.Constants;
import com.microsoft.azure.storage.OperationContext;
import com.microsoft.azure.storage.StorageErrorCodeStrings;
import com.microsoft.azure.storage.StorageException;
import com.microsoft.azure.storage.core.SR;
/**
* Reserved for internal use. A class used to read Table entities.
*/
final class TableDeserializer {
/**
* Used to create Json parsers and generators.
*/
private static JsonFactory jsonFactory = new JsonFactory();
/**
* Reserved for internal use. Parses the operation response as a collection of entities. Reads entity data from the
* specified input stream using the specified class type and optionally projects each entity result with the
* specified resolver into an {@link ODataPayload} containing a collection of {@link TableResult} objects.
*
* @param inStream
* The <code>InputStream</code> to read the data to parse from.
* @param clazzType
* The class type <code>T</code> implementing {@link TableEntity} for the entities returned. Set to
* <code>null</code> to ignore the returned entities and copy only response properties into the
* {@link TableResult} objects.
* @param resolver
* An {@link EntityResolver} instance to project the entities into instances of type <code>R</code>. Set
* to <code>null</code> to return the entities as instances of the class type <code>T</code>.
* @param opContext
* An {@link OperationContext} object used to track the execution of the operation.
* @return
* An {@link ODataPayload} containing a collection of {@link TableResult} objects with the parsed operation
* response.
* @throws InstantiationException
* if an error occurs while constructing the result.
* @throws IllegalAccessException
* if an error occurs in reflection while parsing the result.
* @throws StorageException
* if a storage service error occurs.
* @throws IOException
* if an error occurs while accessing the stream.
* @throws JsonParseException
* if an error occurs while parsing the stream.
*/
@SuppressWarnings("unchecked")
static <T extends TableEntity, R> ODataPayload<?> parseQueryResponse(final InputStream inStream,
final TableRequestOptions options, Class<T> clazzType, final EntityResolver<R> resolver,
final OperationContext opContext) throws InstantiationException, IllegalAccessException,
StorageException, JsonParseException, IOException {
ODataPayload<T> corePayload = null;
ODataPayload<R> resolvedPayload = null;
ODataPayload<?> commonPayload = null;
JsonParser parser = createJsonParserFromStream(inStream);
try {
if (resolver != null) {
resolvedPayload = new ODataPayload<R>();
commonPayload = resolvedPayload;
}
else {
corePayload = new ODataPayload<T>();
commonPayload = corePayload;
}
if (!parser.hasCurrentToken()) {
parser.nextToken();
}
ODataUtilities.assertIsStartObjectJsonToken(parser);
// move into data
parser.nextToken();
// if there is a clazz type and if JsonNoMetadata, create a classProperties dictionary to use for type inference once
// instead of querying the cache many times
HashMap<String, PropertyPair> classProperties = null;
if (options.getTablePayloadFormat() == TablePayloadFormat.JsonNoMetadata && clazzType != null) {
classProperties = PropertyPair.generatePropertyPairs(clazzType);
}
while (parser.getCurrentToken() != null) {
if (parser.getCurrentToken() == JsonToken.FIELD_NAME
&& parser.getCurrentName().equals(ODataConstants.VALUE)) {
// move to start of array
parser.nextToken();
ODataUtilities.assertIsStartArrayJsonToken(parser);
// go to properties
parser.nextToken();
while (parser.getCurrentToken() == JsonToken.START_OBJECT) {
final TableResult res = parseJsonEntity(parser, clazzType, classProperties, resolver, options,
opContext);
if (corePayload != null) {
corePayload.tableResults.add(res);
}
if (resolver != null) {
resolvedPayload.results.add((R) res.getResult());
}
else {
corePayload.results.add((T) res.getResult());
}
parser.nextToken();
}
ODataUtilities.assertIsEndArrayJsonToken(parser);
}
parser.nextToken();
}
}
finally {
parser.close();
}
return commonPayload;
}
/**
* Reserved for internal use. Parses the operation response as an entity. Reads entity data from the specified
* <code>JsonParser</code> using the specified class type and optionally projects the entity result with the
* specified resolver into a {@link TableResult} object.
*
* @param parser
* The <code>JsonParser</code> to read the data to parse from.
* @param httpStatusCode
* The HTTP status code returned with the operation response.
* @param clazzType
* The class type <code>T</code> implementing {@link TableEntity} for the entity returned. Set to
* <code>null</code> to ignore the returned entity and copy only response properties into the
* {@link TableResult} object.
* @param resolver
* An {@link EntityResolver} instance to project the entity into an instance of type <code>R</code>. Set
* to <code>null</code> to return the entitys as instance of the class type <code>T</code>.
* @param opContext
* An {@link OperationContext} object used to track the execution of the operation.
* @return
* A {@link TableResult} object with the parsed operation response.
* @throws InstantiationException
* if an error occurs while constructing the result.
* @throws IllegalAccessException
* if an error occurs in reflection while parsing the result.
* @throws StorageException
* if a storage service error occurs.
* @throws IOException
* if an error occurs while accessing the stream.
* @throws JsonParseException
* if an error occurs while parsing the stream.
*/
static <T extends TableEntity, R> TableResult parseSingleOpResponse(final InputStream inStream,
final TableRequestOptions options, final int httpStatusCode, final Class<T> clazzType,
final EntityResolver<R> resolver, final OperationContext opContext) throws
InstantiationException, IllegalAccessException, StorageException, JsonParseException, IOException {
JsonParser parser = createJsonParserFromStream(inStream);
try {
final TableResult res = parseJsonEntity(parser, clazzType,
null /*HashMap<String, PropertyPair> classProperties*/, resolver, options, opContext);
res.setHttpStatusCode(httpStatusCode);
return res;
}
finally {
parser.close();
}
}
/**
* Reserved for internal use. Parses the operation response as an entity. Parses the result returned in the
* specified stream in JSON format into a {@link TableResult} containing an entity of the specified class type
* projected using the specified resolver.
*
* @param parser
* The <code>JsonParser</code> to read the data to parse from.
* @param clazzType
* The class type <code>T</code> implementing {@link TableEntity} for the entity returned. Set to
* <code>null</code> to ignore the returned entity and copy only response properties into the
* {@link TableResult} object.
* @param resolver
* An {@link EntityResolver} instance to project the entity into an instance of type <code>R</code>. Set
* to <code>null</code> to return the entity as an instance of the class type <code>T</code>.
* @param opContext
* An {@link OperationContext} object used to track the execution of the operation.
* @return
* A {@link TableResult} containing the parsed entity result of the operation.
* @throws IOException
* if an error occurs while accessing the stream.
* @throws InstantiationException
* if an error occurs while constructing the result.
* @throws IllegalAccessException
* if an error occurs in reflection while parsing the result.
* @throws StorageException
* if a storage service error occurs.
* @throws IOException
* if an error occurs while accessing the stream.
* @throws JsonParseException
* if an error occurs while parsing the stream.
*/
private static <T extends TableEntity, R> TableResult parseJsonEntity(final JsonParser parser,
final Class<T> clazzType, HashMap<String, PropertyPair> classProperties, final EntityResolver<R> resolver,
final TableRequestOptions options, final OperationContext opContext) throws JsonParseException,
IOException, StorageException, InstantiationException, IllegalAccessException {
final TableResult res = new TableResult();
final HashMap<String, EntityProperty> properties = new HashMap<String, EntityProperty>();
if (!parser.hasCurrentToken()) {
parser.nextToken();
}
ODataUtilities.assertIsStartObjectJsonToken(parser);
parser.nextToken();
// get all metadata, if present
while (parser.getCurrentName().startsWith(ODataConstants.ODATA_PREFIX)) {
final String name = parser.getCurrentName().substring(ODataConstants.ODATA_PREFIX.length());
// get the value token
parser.nextToken();
if (name.equals(ODataConstants.ETAG)) {
String etag = parser.getValueAsString();
res.setEtag(etag);
}
// get the key token
parser.nextToken();
}
if (resolver == null && clazzType == null) {
return res;
}
// get object properties
while (parser.getCurrentToken() != JsonToken.END_OBJECT) {
String key = Constants.EMPTY_STRING;
String val = Constants.EMPTY_STRING;
EdmType edmType = null;
// checks if this property is preceded by an OData property type annotation
if (options.getTablePayloadFormat() != TablePayloadFormat.JsonNoMetadata
&& parser.getCurrentName().endsWith(ODataConstants.ODATA_TYPE_SUFFIX)) {
parser.nextToken();
edmType = EdmType.parse(parser.getValueAsString());
parser.nextValue();
key = parser.getCurrentName();
val = parser.getValueAsString();
}
else {
key = parser.getCurrentName();
parser.nextToken();
val = parser.getValueAsString();
edmType = evaluateEdmType(parser.getCurrentToken(), parser.getValueAsString());
}
final EntityProperty newProp = new EntityProperty(val, edmType);
properties.put(key, newProp);
parser.nextToken();
}
String partitionKey = null;
String rowKey = null;
Date timestamp = null;
String etag = null;
// Remove core properties from map and set individually
EntityProperty tempProp = properties.remove(TableConstants.PARTITION_KEY);
if (tempProp != null) {
partitionKey = tempProp.getValueAsString();
}
tempProp = properties.remove(TableConstants.ROW_KEY);
if (tempProp != null) {
rowKey = tempProp.getValueAsString();
}
tempProp = properties.remove(TableConstants.TIMESTAMP);
if (tempProp != null) {
timestamp = tempProp.getValueAsDate();
if (res.getEtag() == null) {
etag = getETagFromTimestamp(tempProp.getValueAsString());
res.setEtag(etag);
}
}
// do further processing for type if JsonNoMetdata by inferring type information via resolver or clazzType
if (options.getTablePayloadFormat() == TablePayloadFormat.JsonNoMetadata
&& (options.getPropertyResolver() != null || clazzType != null)) {
if (options.getPropertyResolver() != null) {
for (final Entry<String, EntityProperty> p : properties.entrySet()) {
final String key = p.getKey();
final String value = p.getValue().getValueAsString();
EdmType edmType;
// try to use the property resolver to get the type
try {
edmType = options.getPropertyResolver().propertyResolver(partitionKey, rowKey, key, value);
}
catch (Exception e) {
throw new StorageException(StorageErrorCodeStrings.INTERNAL_ERROR, SR.CUSTOM_RESOLVER_THREW,
Constants.HeaderConstants.HTTP_UNUSED_306, null, e);
}
// try to create a new entity property using the returned type
try {
final EntityProperty newProp = new EntityProperty(value, edmType);
properties.put(p.getKey(), newProp);
}
catch (IllegalArgumentException e) {
throw new StorageException(StorageErrorCodeStrings.INVALID_TYPE, String.format(
SR.FAILED_TO_PARSE_PROPERTY, key, value, edmType),
Constants.HeaderConstants.HTTP_UNUSED_306, null, e);
}
}
}
else if (clazzType != null) {
if (classProperties == null) {
classProperties = PropertyPair.generatePropertyPairs(clazzType);
}
for (final Entry<String, EntityProperty> p : properties.entrySet()) {
PropertyPair propPair = classProperties.get(p.getKey());
if (propPair != null) {
final EntityProperty newProp = new EntityProperty(p.getValue().getValueAsString(),
propPair.type);
properties.put(p.getKey(), newProp);
}
}
}
}
// set the result properties, now that they are appropriately parsed
res.setProperties(properties);
// use resolver if provided, else create entity based on clazz type
if (resolver != null) {
res.setResult(resolver.resolve(partitionKey, rowKey, timestamp, res.getProperties(), res.getEtag()));
}
else if (clazzType != null) {
// Generate new entity and return
final T entity = clazzType.newInstance();
entity.setEtag(res.getEtag());
entity.setPartitionKey(partitionKey);
entity.setRowKey(rowKey);
entity.setTimestamp(timestamp);
entity.readEntity(res.getProperties(), opContext);
res.setResult(entity);
}
return res;
}
private static String getETagFromTimestamp(String timestampString) throws UnsupportedEncodingException {
timestampString = URLEncoder.encode(timestampString, Constants.UTF8_CHARSET);
return "W/\"datetime'" + timestampString + "'\"";
}
private static EdmType evaluateEdmType(JsonToken token, String value) {
EdmType edmType = null;
if (token == JsonToken.VALUE_NULL) {
edmType = EdmType.NULL;
}
else if (token == JsonToken.VALUE_FALSE || token == JsonToken.VALUE_TRUE) {
edmType = EdmType.BOOLEAN;
}
else if (token == JsonToken.VALUE_NUMBER_FLOAT) {
edmType = EdmType.DOUBLE;
}
else if (token == JsonToken.VALUE_NUMBER_INT) {
edmType = EdmType.INT32;
}
else {
edmType = EdmType.STRING;
}
return edmType;
}
private static JsonParser createJsonParserFromStream(final InputStream streamRef) throws JsonParseException,
IOException {
JsonParser parser = jsonFactory.createParser(streamRef);
// allows handling of infinity, -infinity, and NaN for Doubles
return parser.enable(JsonParser.Feature.ALLOW_NON_NUMERIC_NUMBERS);
}
}