io.nats.client.impl.NatsObjectStore Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jnats Show documentation
Show all versions of jnats Show documentation
Client library for working with the NATS messaging system.
// Copyright 2022 The NATS Authors
// 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 io.nats.client.impl;
import io.nats.client.*;
import io.nats.client.api.*;
import io.nats.client.support.DateTimeUtils;
import io.nats.client.support.Digester;
import io.nats.client.support.Validator;
import java.io.*;
import java.nio.file.Files;
import java.security.NoSuchAlgorithmException;
import java.time.Duration;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import static io.nats.client.support.NatsConstants.GREATER_THAN;
import static io.nats.client.support.NatsJetStreamClientError.*;
import static io.nats.client.support.NatsObjectStoreUtil.*;
public class NatsObjectStore extends NatsFeatureBase implements ObjectStore {
private final ObjectStoreOptions oso;
private final String bucketName;
private final String rawChunkPrefix;
private final String pubSubChunkPrefix;
private final String rawMetaPrefix;
private final String pubSubMetaPrefix;
NatsObjectStore(NatsConnection connection, String bucketName, ObjectStoreOptions oso) throws IOException {
super(connection, oso);
this.oso = oso;
this.bucketName = Validator.validateBucketName(bucketName, true);
streamName = toStreamName(bucketName);
rawChunkPrefix = toChunkPrefix(bucketName);
rawMetaPrefix = toMetaPrefix(bucketName);
if (oso == null) {
pubSubChunkPrefix = rawChunkPrefix;
pubSubMetaPrefix = rawMetaPrefix;
}
else if (oso.getJetStreamOptions().isDefaultPrefix()) {
pubSubChunkPrefix = rawChunkPrefix;
pubSubMetaPrefix = rawMetaPrefix;
}
else {
pubSubChunkPrefix = oso.getJetStreamOptions().getPrefix() + rawChunkPrefix;
pubSubMetaPrefix = oso.getJetStreamOptions().getPrefix() + rawMetaPrefix;
}
}
String rawChunkSubject(String nuid) {
return rawChunkPrefix + nuid;
}
String pubSubChunkSubject(String nuid) {
return pubSubChunkPrefix + nuid;
}
String rawMetaSubject(String name) {
return rawMetaPrefix + encodeForSubject(name);
}
String rawAllMetaSubject() {
return rawMetaPrefix + GREATER_THAN;
}
String pubSubMetaSubject(String name) {
return pubSubMetaPrefix + encodeForSubject(name);
}
/**
* {@inheritDoc}
*/
@Override
public String getBucketName() {
return bucketName;
}
private ObjectInfo publishMeta(ObjectInfo info) throws IOException, JetStreamApiException {
js.publish(NatsMessage.builder()
.subject(rawMetaSubject(info.getObjectName()))
.headers(getMetaHeaders())
.data(info.serialize())
.build()
);
return ObjectInfo.builder(info).modified(DateTimeUtils.gmtNow()).build();
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo put(ObjectMeta meta, InputStream inputStream) throws IOException, JetStreamApiException, NoSuchAlgorithmException {
Validator.validateNotNull(meta, "ObjectMeta");
Validator.validateNotNull(meta.getObjectName(), "ObjectMeta name");
Validator.validateNotNull(inputStream, "InputStream");
if (meta.getObjectMetaOptions().getLink() != null) {
throw OsLinkNotAllowOnPut.instance();
}
String nuid = NUID.nextGlobal();
String chunkSubject = rawChunkSubject(nuid);
int chunkSize = meta.getObjectMetaOptions().getChunkSize();
if (chunkSize <= 0) {
chunkSize = DEFAULT_CHUNK_SIZE;
}
try {
Digester digester = new Digester();
long totalSize = 0; // track total bytes read to make sure
int chunks = 0;
// working with chunkSize number of bytes each time.
byte[] buffer = new byte[chunkSize];
int red = inputStream.read(buffer);
while (red != -1) { // keep reading while not receiving the end of file mark (-1)
// copy if red is less than buffer length
byte[] payload = red == buffer.length ? buffer : Arrays.copyOfRange(buffer, 0, red);
// digest the actual bytes
digester.update(payload);
// publish the payload
js.publish(chunkSubject, payload);
// track total chunks and bytes
chunks++;
totalSize += red;
red = inputStream.read(buffer);
}
return publishMeta(ObjectInfo.builder(bucketName, meta)
.size(totalSize)
.chunks(chunks)
.nuid(nuid)
.chunkSize(chunkSize)
.digest(digester.getDigestEntry())
.build());
}
catch (IOException | JetStreamApiException | NoSuchAlgorithmException e) {
try {
jsm.purgeStream(streamName, PurgeOptions.subject(rawChunkSubject(nuid)));
}
catch (Exception ignore) {}
throw e;
}
finally {
try { inputStream.close(); } catch (IOException ignore) {}
}
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo put(String objectName, InputStream inputStream) throws IOException, JetStreamApiException, NoSuchAlgorithmException {
return put(ObjectMeta.objectName(objectName), inputStream);
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo put(String objectName, byte[] input) throws IOException, JetStreamApiException, NoSuchAlgorithmException {
return put(ObjectMeta.objectName(objectName), new ByteArrayInputStream(input));
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo put(File file) throws IOException, JetStreamApiException, NoSuchAlgorithmException {
return put(ObjectMeta.objectName(file.getName()), Files.newInputStream(file.toPath()));
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo get(String objectName, OutputStream out) throws IOException, JetStreamApiException, InterruptedException, NoSuchAlgorithmException {
ObjectInfo oi = getInfo(objectName, false);
if (oi == null) {
throw OsObjectNotFound.instance();
}
if (oi.isLink()) {
ObjectLink link = oi.getLink();
if (link.isBucketLink()) {
throw OsGetLinkToBucket.instance();
}
// is the link in the same bucket
if (link.getBucket().equals(bucketName)) {
return get(link.getObjectName(), out);
}
// different bucket
// get the store for the linked bucket, then get the linked object
return js.conn.objectStore(link.getBucket(), oso).get(link.getObjectName(), out);
}
Digester digester = new Digester();
long totalBytes = 0;
long totalChunks = 0;
// if there is one chunk, just go get the message directly and we're done.
if (oi.getChunks() == 1) {
MessageInfo mi = jsm.getLastMessage(streamName, rawChunkSubject(oi.getNuid()));
byte[] data = mi.getData();
// track the byte count and chunks
// update the digest
// write the bytes to the output file
totalBytes = data.length;
totalChunks = 1;
digester.update(data);
out.write(data);
}
else {
JetStreamSubscription sub = js.subscribe(rawChunkSubject(oi.getNuid()),
PushSubscribeOptions.builder().stream(streamName).ordered(true).build());
Message m = sub.nextMessage(Duration.ofSeconds(1));
while (m != null) {
byte[] data = m.getData();
// track the byte count and chunks
// update the digest
// write the bytes to the output file
totalBytes += data.length;
totalChunks++;
digester.update(data);
out.write(data);
// read until the subject is complete
m = sub.nextMessage(Duration.ofSeconds(1));
}
sub.unsubscribe();
}
out.flush();
if (totalBytes != oi.getSize()) { throw OsGetSizeMismatch.instance(); }
if (totalChunks != oi.getChunks()) { throw OsGetChunksMismatch.instance(); }
if (!digester.matches(oi.getDigest())) { throw OsGetDigestMismatch.instance(); }
return oi;
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo getInfo(String objectName) throws IOException, JetStreamApiException {
return getInfo(objectName, false);
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo getInfo(String objectName, boolean includingDeleted) throws IOException, JetStreamApiException {
MessageInfo mi = _getLast(rawMetaSubject(objectName));
if (mi == null) {
return null;
}
ObjectInfo info = new ObjectInfo(mi);
return includingDeleted || !info.isDeleted() ? info : null;
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo updateMeta(String objectName, ObjectMeta meta) throws IOException, JetStreamApiException {
Validator.validateNotNull(objectName, "object name");
Validator.validateNotNull(meta, "ObjectMeta");
Validator.validateNotNull(meta.getObjectName(), "ObjectMeta name");
ObjectInfo currentInfo = getInfo(objectName, true);
if (currentInfo == null) {
throw OsObjectNotFound.instance();
}
if (currentInfo.isDeleted()) {
throw OsObjectIsDeleted.instance();
}
boolean nameChange = !objectName.equals(meta.getObjectName());
if (nameChange) {
if (getInfo(meta.getObjectName(), false) != null) {
throw OsObjectAlreadyExists.instance();
}
}
currentInfo = publishMeta(ObjectInfo.builder(currentInfo)
.objectName(meta.getObjectName()) // replace the name
.description(meta.getDescription()) // replace the description
.headers(meta.getHeaders()) // replace the headers
.build());
if (nameChange) {
// delete the meta from the old name via purge stream for subject
jsm.purgeStream(streamName, PurgeOptions.subject(rawMetaSubject(objectName)));
}
return currentInfo;
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo delete(String objectName) throws IOException, JetStreamApiException {
ObjectInfo info = getInfo(objectName, true);
if (info == null) {
throw OsObjectNotFound.instance();
}
if (info.isDeleted()) {
return info;
}
ObjectInfo deleted = publishMeta(ObjectInfo.builder(info)
.deleted(true)
.size(0)
.chunks(0)
.digest(null)
.build());
jsm.purgeStream(streamName, PurgeOptions.subject(rawChunkSubject(info.getNuid())));
return deleted;
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo addLink(String objectName, ObjectInfo toInfo) throws IOException, JetStreamApiException {
Validator.validateNotNull(objectName, "object name");
Validator.validateNotNull(toInfo, "Link-To ObjectInfo");
Validator.validateNotNull(toInfo.getObjectName(), "Link-To ObjectMeta");
if (toInfo.isDeleted()) {
throw OsObjectIsDeleted.instance();
}
if (toInfo.isLink()) {
throw OsCantLinkToLink.instance();
}
ObjectInfo info = getInfo(objectName, false);
if (info != null && !info.isLink()) {
throw OsObjectAlreadyExists.instance();
}
return publishMeta(ObjectInfo.builder(bucketName, objectName)
.nuid(NUID.nextGlobal())
.objectLink(toInfo.getBucket(), toInfo.getObjectName())
.build());
}
/**
* {@inheritDoc}
*/
@Override
public ObjectInfo addBucketLink(String objectName, ObjectStore toStore) throws IOException, JetStreamApiException {
Validator.validateNotNull(objectName, "object name");
Validator.validateNotNull(toStore, "Link-To ObjectStore");
ObjectInfo info = getInfo(objectName, false);
if (info != null && !info.isLink()) {
throw OsObjectAlreadyExists.instance();
}
return publishMeta(ObjectInfo.builder(bucketName, objectName)
.nuid(NUID.nextGlobal())
.bucketLink(toStore.getBucketName())
.build());
}
/**
* {@inheritDoc}
*
* @return
*/
@Override
public ObjectStoreStatus seal() throws IOException, JetStreamApiException {
StreamInfo si = jsm.getStreamInfo(streamName);
si = jsm.updateStream(StreamConfiguration.builder(si.getConfiguration()).seal().build());
return new ObjectStoreStatus(si);
}
/**
* {@inheritDoc}
*/
@Override
public List getList() throws IOException, JetStreamApiException, InterruptedException {
List list = new ArrayList<>();
visitSubject(rawAllMetaSubject(), DeliverPolicy.LastPerSubject, false, true, m -> {
ObjectInfo oi = new ObjectInfo(m);
if (!oi.isDeleted()) {
list.add(oi);
}
});
return list;
}
@Override
public NatsObjectStoreWatchSubscription watch(ObjectStoreWatcher watcher, ObjectStoreWatchOption... watchOptions) throws IOException, JetStreamApiException, InterruptedException {
return new NatsObjectStoreWatchSubscription(this, watcher, watchOptions);
}
/**
* {@inheritDoc}
*/
@Override
public ObjectStoreStatus getStatus() throws IOException, JetStreamApiException {
return new ObjectStoreStatus(jsm.getStreamInfo(streamName));
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy