Package com.github.ddth.queue.impl

Class MongodbQueue<ID,DATA>

java.lang.Object

com.github.ddth.queue.impl.AbstractQueue<ID,DATA>

com.github.ddth.queue.impl.AbstractEphemeralSupportQueue<ID,DATA>

com.github.ddth.queue.impl.MongodbQueue<ID,DATA>

All Implemented Interfaces:

IQueue<ID,DATA>, AutoCloseable

Direct Known Subclasses:

BaseUniversalMongodbQueue

public abstract class MongodbQueue<ID,DATA>
extends AbstractEphemeralSupportQueue<ID,DATA>

(Experimental) MongoDB implementation of IQueue.

• Queue-size support: yes
• Ephemeral storage support: yes
• Ephemeral-size support: yes

Since:

0.7.1

Author:

Thanh Ba Nguyen

Nested Class Summary

Nested classes/interfaces inherited from class com.github.ddth.queue.impl.AbstractQueue

AbstractQueue.PutToQueueCase

Field Summary

Fields

Modifier and Type	Field	Description
static String	COLLECTION_FIELD_EPHEMERAL_KEY
static String	COLLECTION_FIELD_ID
static String	COLLECTION_FIELD_QUEUE_DATA
static String	COLLECTION_FIELD_QUEUE_TIME
static String	COLLECTION_FIELD_TIME
static String	DEFAULT_COLLECTION_NAME
static String	DEFAULT_CONN_STR

Fields inherited from interface com.github.ddth.queue.IQueue

SIZE_NOT_SUPPORTED

Constructor Summary

Constructors

Constructor	Description
MongodbQueue()

Method Summary

Modifier and Type	Method	Description
protected com.mongodb.client.MongoClient	buildMongoClient()	Build a new MongoClient instance.
void	destroy()	Destroy method.
protected boolean	doPutToQueue(IQueueMessage<ID,DATA> msg, AbstractQueue.PutToQueueCase queueCase)	Put a message to the queue storage.
int	ephemeralSize()	Get number of items currently in ephemeral storage.
void	finish(IQueueMessage<ID,DATA> msg)	Called when finish processing the message to cleanup ephemeral storage.
protected IQueueMessage<ID,DATA>	fromDocument(org.bson.Document doc)
protected com.mongodb.client.MongoCollection<org.bson.Document>	getCollection()
String	getCollectionName()	Name of MongoDB collection to store queue messages.
String	getConnectionString()	MongoDB's connection string (see http://mongodb.github.io/mongo-java-driver/3.10/driver/getting-started/quick-start/).
protected com.mongodb.client.MongoDatabase	getDatabase()
String	getDatabaseName()	Name of MongoDB database to store data.
protected com.mongodb.client.MongoClient	getMongoClient()	Getter for mongoClient.
Collection<IQueueMessage<ID,DATA>>	getOrphanMessages(long thresholdTimestampMs)	Get all orphan messages (messages that were left in ephemeral storage for a long time).
MongodbQueue<ID,DATA>	init()	Init method.
protected void	initCollection()	Initialize collection: Check if collection exists. If collection does not exist, create collection and indexes.
protected boolean	insertToCollection(IQueueMessage<ID,DATA> msg)	Insert a new message to collection.
int	queueSize()	Get number of items currently in queue storage.
MongodbQueue<ID,DATA>	setCollectionName(String collectionName)	Name of MongoDB collection to store queue messages.
MongodbQueue<ID,DATA>	setConnectionString(String connectionString)	MongoDB's connection string (see http://mongodb.github.io/mongo-java-driver/3.10/driver/getting-started/quick-start/).
MongodbQueue<ID,DATA>	setDatabaseName(String databaseName)	Name of MongoDB database to store data.
MongodbQueue<ID,DATA>	setMongoClient(com.mongodb.client.MongoClient mongoClient)	Setter for mongoClient.
protected MongodbQueue<ID,DATA>	setMongoClient(com.mongodb.client.MongoClient mongoClient, boolean setMyOwnMongoClient)	Setter for mongoClient.
IQueueMessage<ID,DATA>	take()	Take a message out of queue.
protected org.bson.Document	toDocument(IQueueMessage<ID,DATA> msg)
protected boolean	upsertToCollection(IQueueMessage<ID,DATA> msg)	Insert/Update the message to collection.

Methods inherited from class com.github.ddth.queue.impl.AbstractEphemeralSupportQueue

getEphemeralDisabled, getEphemeralMaxSize, isEphemeralDisabled, setEphemeralDisabled, setEphemeralMaxSize

Methods inherited from class com.github.ddth.queue.impl.AbstractQueue

close, createMessage, createMessage, createMessage, deserialize, deserialize, getMessageFactory, getQueueName, getSerDeser, queue, requeue, requeueSilent, serialize, setMessageFactory, setQueueName, setSerDeser

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_CONN_STR

public static final String DEFAULT_CONN_STR

See Also:

Constant Field Values

DEFAULT_COLLECTION_NAME

public static final String DEFAULT_COLLECTION_NAME

See Also:

Constant Field Values

COLLECTION_FIELD_ID

public static final String COLLECTION_FIELD_ID

See Also:

Constant Field Values

COLLECTION_FIELD_TIME

public static final String COLLECTION_FIELD_TIME

See Also:

Constant Field Values

COLLECTION_FIELD_QUEUE_TIME

public static final String COLLECTION_FIELD_QUEUE_TIME

See Also:

Constant Field Values

COLLECTION_FIELD_QUEUE_DATA

public static final String COLLECTION_FIELD_QUEUE_DATA

See Also:

Constant Field Values

COLLECTION_FIELD_EPHEMERAL_KEY

public static final String COLLECTION_FIELD_EPHEMERAL_KEY

See Also:

Constant Field Values

Constructor Detail

MongodbQueue

public MongodbQueue()

Method Detail

getConnectionString

public String getConnectionString()

MongoDB's connection string (see http://mongodb.github.io/mongo-java-driver/3.10/driver/getting-started/quick-start/).

Returns:

setConnectionString

public MongodbQueue<ID,DATA> setConnectionString(String connectionString)

MongoDB's connection string (see http://mongodb.github.io/mongo-java-driver/3.10/driver/getting-started/quick-start/).

Parameters:

connectionString -

Returns:

getDatabaseName

public String getDatabaseName()

Name of MongoDB database to store data.

Returns:

setDatabaseName

public MongodbQueue<ID,DATA> setDatabaseName(String databaseName)

Name of MongoDB database to store data.

Parameters:

databaseName -

Returns:

getCollectionName

public String getCollectionName()

Name of MongoDB collection to store queue messages.

Returns:

setCollectionName

public MongodbQueue<ID,DATA> setCollectionName(String collectionName)

Name of MongoDB collection to store queue messages.

Parameters:

collectionName -

Returns:

getMongoClient

protected com.mongodb.client.MongoClient getMongoClient()

Getter for mongoClient.

Returns:

setMongoClient

public MongodbQueue<ID,DATA> setMongoClient(com.mongodb.client.MongoClient mongoClient)

Setter for mongoClient.

Parameters:

mongoClient -

Returns:

setMongoClient

protected MongodbQueue<ID,DATA> setMongoClient(com.mongodb.client.MongoClient mongoClient,
                                                     boolean setMyOwnMongoClient)

Setter for mongoClient.

Parameters:

mongoClient -

setMyOwnMongoClient -

Returns:

getDatabase

protected com.mongodb.client.MongoDatabase getDatabase()

getCollection

protected com.mongodb.client.MongoCollection<org.bson.Document> getCollection()

initCollection

protected void initCollection()

Initialize collection:

• Check if collection exists.
• If collection does not exist, create collection and indexes.

buildMongoClient

protected com.mongodb.client.MongoClient buildMongoClient()

Build a new MongoClient instance.

Returns:

init

public MongodbQueue<ID,DATA> init()
                                 throws Exception

Init method.

Overrides:

init in class AbstractQueue<ID,DATA>

Returns:

Throws:

Exception

destroy

public void destroy()

Destroy method.

Overrides:

destroy in class AbstractQueue<ID,DATA>

toDocument

protected org.bson.Document toDocument(IQueueMessage<ID,DATA> msg)

fromDocument

protected IQueueMessage<ID,DATA> fromDocument(org.bson.Document doc)

upsertToCollection

protected boolean upsertToCollection(IQueueMessage<ID,DATA> msg)

Insert/Update the message to collection.

Parameters:

msg -

Returns:

insertToCollection

protected boolean insertToCollection(IQueueMessage<ID,DATA> msg)

Insert a new message to collection.

Parameters:

msg -

Returns:

doPutToQueue

protected boolean doPutToQueue(IQueueMessage<ID,DATA> msg,
                               AbstractQueue.PutToQueueCase queueCase)

Put a message to the queue storage.

Sub-class implements this method.

Specified by:

doPutToQueue in class AbstractQueue<ID,DATA>

Returns:

finish

public void finish(IQueueMessage<ID,DATA> msg)

Called when finish processing the message to cleanup ephemeral storage.

Implementation flow:

• Remove message from ephemeral storage.

Note: ephemeral storage implementation is optional, depends on implementation.

take

public IQueueMessage<ID,DATA> take()
                                  throws QueueException.EphemeralIsFull

Take a message out of queue.

Implementation flow:

• Read message from head of queue storage.
• Write message to ephemeral storage.
• Remove message from queue storage.

Note: ephemeral storage implementation is optional, depends on implementation.

Returns:

Throws:

QueueException.EphemeralIsFull - if the ephemeral storage is full

getOrphanMessages

public Collection<IQueueMessage<ID,DATA>> getOrphanMessages(long thresholdTimestampMs)

Get all orphan messages (messages that were left in ephemeral storage for a long time).

Parameters:

thresholdTimestampMs - message is orphan if message's timestampMillis + thresholdTimestampMs < now . Which means getOrphanMessages(10000) will return orphan messages that have stayed in ephemeral storage for more than 10000 milliseconds.

Returns:

null or empty collection if there is no orphan message

queueSize

public int queueSize()

Get number of items currently in queue storage.

Returns:

negative number if queue size can not be queried

ephemeralSize

public int ephemeralSize()

Get number of items currently in ephemeral storage.

Note: ephemeral storage implementation is optional, depends on implementation.

Returns:

negative number if ephemeral size can not be queried