org.swisspush.gateleen.queue.queuing.circuitbreaker

Interface QueueCircuitBreakerStorage

All Known Implementing Classes:

RedisQueueCircuitBreakerStorage

public interface QueueCircuitBreakerStorage

Provides storage access for the QueueCircuitBreaker.

Author:

https://github.com/mcweba [Marc-Andre Weber]

Method Summary

Modifier and Type	Method and Description
io.vertx.core.Future<Void>	closeAllCircuits() Closes all non-closed circuits.
io.vertx.core.Future<Void>	closeAndRemoveCircuit(PatternAndCircuitHash patternAndCircuitHash) Closes the circuit and removes all circuit information from storage.
io.vertx.core.Future<Void>	closeCircuit(PatternAndCircuitHash patternAndCircuitHash) Closes the circuit.
io.vertx.core.Future<io.vertx.core.json.JsonObject>	getAllCircuits() Get the information (status, failRatio and circuit) of all circuits.
io.vertx.core.Future<io.vertx.core.json.JsonObject>	getQueueCircuitInformation(String circuitHash) Get the information (status, failRatio and circuit) of the circuit represented by the provided circuitHash.
io.vertx.core.Future<QueueCircuitState>	getQueueCircuitState(PatternAndCircuitHash patternAndCircuitHash) Get the actual QueueCircuitState of the provided patternAndCircuitHash object.
io.vertx.core.Future<QueueCircuitState>	getQueueCircuitState(String circuitHash) Get the actual QueueCircuitState of the provided circuitHash.
io.vertx.core.Future<Void>	lockQueue(String queueName, PatternAndCircuitHash patternAndCircuitHash) Mark the queueName as a locked queue of the circuit representing the provided patternAndCircuitHash.
io.vertx.core.Future<String>	popQueueToUnlock() Get the next queue to unlock.
io.vertx.core.Future<Void>	reOpenCircuit(PatternAndCircuitHash patternAndCircuitHash) Re-Opens the (half-open) circuit again.
io.vertx.core.Future<Long>	setOpenCircuitsToHalfOpen() Changes the status of all circuits having a status equals QueueCircuitState.OPEN to QueueCircuitState.HALF_OPEN.
io.vertx.core.Future<List<String>>	unlockSampleQueues() Get a list of sample queues of all circuits having a status equals QueueCircuitState.HALF_OPEN.
io.vertx.core.Future<UpdateStatisticsResult>	updateStatistics(PatternAndCircuitHash patternAndCircuitHash, String uniqueRequestID, long timestamp, int errorThresholdPercentage, long entriesMaxAgeMS, long minQueueSampleCount, long maxQueueSampleCount, QueueResponseType queueResponseType) Updates the statistics of the corresponding circuit based on the provided patternAndCircuitHash.

Method Detail

getQueueCircuitState

io.vertx.core.Future<QueueCircuitState> getQueueCircuitState(PatternAndCircuitHash patternAndCircuitHash)

Get the actual QueueCircuitState of the provided patternAndCircuitHash object. When no circuit could be found in the storage, QueueCircuitState.CLOSED is returned.

Parameters:

patternAndCircuitHash - circuit information

Returns:

returns the actual QueueCircuitState or QueueCircuitState.CLOSED when no circuit was found

getQueueCircuitState

io.vertx.core.Future<QueueCircuitState> getQueueCircuitState(String circuitHash)

Get the actual QueueCircuitState of the provided circuitHash. When no circuit could be found in the storage, QueueCircuitState.CLOSED is returned.

Parameters:

circuitHash - the hash representing the circuit

Returns:

returns the actual QueueCircuitState or QueueCircuitState.CLOSED when no circuit was found

getQueueCircuitInformation

io.vertx.core.Future<io.vertx.core.json.JsonObject> getQueueCircuitInformation(String circuitHash)

Get the information (status, failRatio and circuit) of the circuit represented by the provided circuitHash.

Parameters:

circuitHash - the hash representing the circuit to get the informations from

Returns:

returns a JsonObject containing the information of the circuit

getAllCircuits

io.vertx.core.Future<io.vertx.core.json.JsonObject> getAllCircuits()

Get the information (status, failRatio and circuit) of all circuits.

Returns:

returns a JsonObject containing the information of all circuits

updateStatistics

io.vertx.core.Future<UpdateStatisticsResult> updateStatistics(PatternAndCircuitHash patternAndCircuitHash,
                                                              String uniqueRequestID,
                                                              long timestamp,
                                                              int errorThresholdPercentage,
                                                              long entriesMaxAgeMS,
                                                              long minQueueSampleCount,
                                                              long maxQueueSampleCount,
                                                              QueueResponseType queueResponseType)

Updates the statistics of the corresponding circuit based on the provided patternAndCircuitHash.

Updating the statistics includes the following steps:

• Record uniqueRequestID as failed when queueResponseType equals QueueResponseType.FAILURE
• Record uniqueRequestID as success when queueResponseType equals QueueResponseType.SUCCESS
• Calculate failRatio based on fail/success records not older than entriesMaxAgeMS
• Change status of corresponding circuit to 'OPEN' when minQueueSampleCount and errorThresholdPercentage is reached
• Remove oldest fail/success records when maxQueueSampleCount is reached

Parameters:

patternAndCircuitHash - the information of the circuit

uniqueRequestID - the unique identifier of the queued request

timestamp - the current timestamp

errorThresholdPercentage - the threshold to change status to 'OPEN' when reached

entriesMaxAgeMS - the maximum age of fail/success records to respect to calculate the failRatio

minQueueSampleCount - the minimum amount of records (unique uniqueRequestIDs) to reach before status can be changed

maxQueueSampleCount - the maximum amount of fail/success records to keep

queueResponseType - the QueueResponseType representing the execution result of the queuedRequest

Returns:

returns an UpdateStatisticsResult object representing the result of the statistics update

lockQueue

io.vertx.core.Future<Void> lockQueue(String queueName,
                                     PatternAndCircuitHash patternAndCircuitHash)

Mark the queueName as a locked queue of the circuit representing the provided patternAndCircuitHash.

Parameters:

queueName - the name of the queue

patternAndCircuitHash - the information of the circuit

Returns:

returns a void future when the queue could be successfully marked as locked

popQueueToUnlock

io.vertx.core.Future<String> popQueueToUnlock()

Get the next queue to unlock. When successful, the queue is removed from the storage.

Returns:

returns a future holding the name of the next queue or null when no queue was found

closeCircuit

io.vertx.core.Future<Void> closeCircuit(PatternAndCircuitHash patternAndCircuitHash)

Closes the circuit.

Closing the circuit includes the following steps:

• Clear statistics of this circuit
• Reset failRatio of this circuit to zero
• Set status of this circuit to 'CLOSED'
• Unlock all queues related to this circuit

Parameters:

patternAndCircuitHash - the information of the circuit

Returns:

returns a void future when circuit could be closed successfully.

closeAndRemoveCircuit

io.vertx.core.Future<Void> closeAndRemoveCircuit(PatternAndCircuitHash patternAndCircuitHash)

Closes the circuit and removes all circuit information from storage.

Parameters:

patternAndCircuitHash - the information of the circuit

Returns:

returns a void future when circuit could be closed and removed successfully.

closeAllCircuits

io.vertx.core.Future<Void> closeAllCircuits()

Closes all non-closed circuits.

Closing all non-closed circuits includes the following steps:

• Clear statistics of all non-closed circuits
• Reset failRatio of all non-closed circuits to zero
• Set status of all non-closed circuits to 'CLOSED'
• Unlock all queues related to all non-closed circuits

Returns:

returns a void future when all non-closed circuits could be closed successfully.

reOpenCircuit

io.vertx.core.Future<Void> reOpenCircuit(PatternAndCircuitHash patternAndCircuitHash)

Re-Opens the (half-open) circuit again. Circuits should be re-opened after a sample queue request was not successful.

Parameters:

patternAndCircuitHash - the information of the circuit

Returns:

returns a void future when the circuit could be re-opened successfully

setOpenCircuitsToHalfOpen

io.vertx.core.Future<Long> setOpenCircuitsToHalfOpen()

Changes the status of all circuits having a status equals QueueCircuitState.OPEN to QueueCircuitState.HALF_OPEN.

Returns:

returns a future holding the amount of circuits updated

unlockSampleQueues

io.vertx.core.Future<List<String>> unlockSampleQueues()

Get a list of sample queues of all circuits having a status equals QueueCircuitState.HALF_OPEN. The sample queues are always the queues which have not been unlocked the longest. Each sample queue of each circuit is then updated to be the 'most recently' unlocked queue.

Returns:

returns a future holding a list of sample queues to unlock