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/**
* Copyright (c) 2012-2017, jcabi.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met: 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer. 2) Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution. 3) Neither the name of the jcabi.com nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.jcabi.dynamo;
import com.amazonaws.AmazonClientException;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.AttributeValueUpdate;
import com.amazonaws.services.dynamodbv2.model.GetItemRequest;
import com.amazonaws.services.dynamodbv2.model.GetItemResult;
import com.amazonaws.services.dynamodbv2.model.ReturnConsumedCapacity;
import com.amazonaws.services.dynamodbv2.model.ReturnValue;
import com.amazonaws.services.dynamodbv2.model.UpdateItemRequest;
import com.amazonaws.services.dynamodbv2.model.UpdateItemResult;
import com.jcabi.aspects.Immutable;
import com.jcabi.aspects.Loggable;
import com.jcabi.immutable.Array;
import com.jcabi.log.Logger;
import java.io.IOException;
import java.util.Collections;
import java.util.Locale;
import java.util.Map;
import java.util.NoSuchElementException;
import lombok.EqualsAndHashCode;
import lombok.ToString;
/**
* Single item/row in a DynamoDB table.
*
* @author Yegor Bugayenko ([email protected])
* @version $Id: 19fcf89a8c08b3dd79231e7d7197a05fae5f71f2 $
* @since 0.1
*/
@Immutable
@Loggable(Loggable.DEBUG)
@ToString
@EqualsAndHashCode(of = { "credentials", "frm", "name", "attributes" })
final class AwsItem implements Item {
/**
* AWS credentials.
*/
private final transient Credentials credentials;
/**
* Frame.
*/
private final transient AwsFrame frm;
/**
* Table name.
*/
private final transient String name;
/**
* Pre-loaded attributes and their values.
*/
private final transient Attributes attributes;
/**
* Table keys.
*/
private final transient Array keys;
/**
* Public ctor.
* @param creds Credentials
* @param frame Frame
* @param table Table name
* @param attrs Loaded already attributes with values
* @param pks Keys of the table
* @checkstyle ParameterNumber (5 lines)
*/
AwsItem(final Credentials creds, final AwsFrame frame,
final String table, final Attributes attrs,
final Array pks) {
this.credentials = creds;
this.frm = frame;
this.name = table;
this.attributes = attrs;
this.keys = pks;
}
@Override
public boolean has(final String attr) throws IOException {
final String attrib = String.format(Locale.ENGLISH, attr);
boolean has = this.attributes.containsKey(attrib);
if (!has) {
final AmazonDynamoDB aws = this.credentials.aws();
try {
final GetItemRequest request = this.makeItemRequestFor(attr);
final long start = System.currentTimeMillis();
final GetItemResult result = aws.getItem(request);
has = result.getItem().get(attrib) != null;
Logger.info(
this, "#has('%s'): %B from DynamoDB, %s, in %[ms]s",
attr, has,
new PrintableConsumedCapacity(
result.getConsumedCapacity()
).print(),
System.currentTimeMillis() - start
);
} catch (final AmazonClientException ex) {
throw new IOException(
String.format(
"failed to check existence of \"%s\" at \"%s\" by %s",
attr, this.name, this.keys
),
ex
);
} finally {
aws.shutdown();
}
}
return has;
}
@Override
public AttributeValue get(final String attr) throws IOException {
final String attrib = String.format(Locale.ENGLISH, attr);
AttributeValue value = this.attributes.get(attrib);
if (value == null) {
final AmazonDynamoDB aws = this.credentials.aws();
try {
final GetItemRequest request = this.makeItemRequestFor(attrib);
final long start = System.currentTimeMillis();
final GetItemResult result = aws.getItem(request);
value = result.getItem().get(attrib);
Logger.info(
this,
// @checkstyle LineLength (1 line)
"#get('%s'): loaded '%[text]s' from DynamoDB, %s, in %[ms]s",
attrib, value,
new PrintableConsumedCapacity(
result.getConsumedCapacity()
).print(),
System.currentTimeMillis() - start
);
} catch (final AmazonClientException ex) {
throw new IOException(
String.format(
"failed to get \"%s\" from \"%s\" by %s",
attr, this.name, this.keys
),
ex
);
} finally {
aws.shutdown();
}
}
if (value == null) {
throw new NoSuchElementException(
String.format("attribute \"%s\" not found", attr)
);
}
return value;
}
@Override
public Map put(final String attr,
final AttributeValueUpdate value) throws IOException {
return this.put(new AttributeUpdates().with(attr, value));
}
@Override
public Map put(
final Map attrs) throws IOException {
final AmazonDynamoDB aws = this.credentials.aws();
final Attributes expected = this.attributes.only(this.keys);
try {
final UpdateItemRequest request = new UpdateItemRequest()
.withTableName(this.name)
.withExpected(expected.asKeys())
.withKey(expected)
.withAttributeUpdates(attrs)
.withReturnConsumedCapacity(ReturnConsumedCapacity.TOTAL)
.withReturnValues(ReturnValue.UPDATED_NEW);
final long start = System.currentTimeMillis();
final UpdateItemResult result = aws.updateItem(request);
Logger.info(
this, "#put('%s'): updated item to DynamoDB, %s, in %[ms]s",
attrs,
new PrintableConsumedCapacity(
result.getConsumedCapacity()
).print(),
System.currentTimeMillis() - start
);
return result.getAttributes();
} catch (final AmazonClientException ex) {
throw new IOException(
String.format(
"failed to put %s into \"%s\" with %s",
attrs, this.name, this.keys
),
ex
);
} finally {
aws.shutdown();
}
}
@Override
public Frame frame() {
return this.frm;
}
/**
* Makes a GetItemRequest for a given attribute.
* @param attr Attribute name
* @return GetItemRequest
*/
private GetItemRequest makeItemRequestFor(final String attr) {
final GetItemRequest request = new GetItemRequest();
request.setTableName(this.name);
request.setAttributesToGet(Collections.singletonList(attr));
request.setKey(this.attributes.only(this.keys));
request.setReturnConsumedCapacity(ReturnConsumedCapacity.TOTAL);
request.setConsistentRead(true);
return request;
}
}
