Distributed James Server — rabbitmq.properties

This configuration helps you configure components using RabbitMQ.

Consult this example to get some examples and hints.

RabbitMQ Configuration

Table 1. rabbitmq.properties content
Property name explanation

uri

the amqp URI pointing to RabbitMQ server. Details about amqp URI format is in RabbitMQ URI Specification

management.uri

the URI pointing to RabbitMQ Management Service. James need to retrieve some information about listing queues from this service in runtime. Details about URI format is in RabbitMQ Management URI

management.user

username used to access management service

management.password

password used to access management service

connection.pool.retries

Configure retries count to retrieve a connection. Exponential backoff is performed between each retries. Optional integer, defaults to 10

connection.pool.min.delay.ms

Configure initial duration (in ms) between two connection retries. Exponential backoff is performed between each retries. Optional integer, defaults to 100

channel.pool.retries

Configure retries count to retrieve a channel. Exponential backoff is performed between each retries. Optional integer, defaults to 3

channel.pool.min.delay.ms

Configure initial duration (in ms) between two channel retries. Exponential backoff is performed between each retries. Optional integer, defaults to 50

channel.pool.size

Configure the size of the channel pool. Optional integer, defaults to 3

ssl.enabled

Is using ssl enabled Optional boolean, defaults to false

ssl.management.enabled

Is using ssl on management api enabled Optional boolean, defaults to false

ssl.validation.strategy

Configure the validation strategy used for rabbitmq connections. Possible values are default, ignore and override. Optional string, defaults to using systemwide ssl configuration

ssl.truststore

Points to the truststore (PKCS12) used for verifying rabbitmq connection. If configured then "ssl.truststore.password" must also be configured, Optional string, defaults to systemwide truststore. "ssl.validation.strategy: override" must be configured if you want to use this

ssl.truststore.password

Configure the truststore password. If configured then "ssl.truststore" must also be configured, Optional string, defaults to empty string. "ssl.validation.strategy: override" must be configured if you want to use this

ssl.hostname.verifier

Configure host name verification. Possible options are default and accept_any_hostname Optional string, defaults to subject alternative name host verifier

ssl.keystore

Points to the keystore(PKCS12) used for client certificate authentication. If configured then "ssl.keystore.password" must also be configured, Optional string, defaults to empty string

ssl.keystore.password

Configure the keystore password. If configured then "ssl.keystore" must also be configured, Optional string, defaults to empty string

RabbitMQ MailQueue Configuration

James mail queue is a component acting like a queue where it can enqueue and dequeue mails. Beside of the basic features, it also allows some extra operations like getting size, browsing all items in the mail queue…​ One of the mailqueue implementation is using RabbitMQ. As RabbitMQ doesn’t offer enough features to implement efficiently all mailqueue operations, this implementation relies on Cassandra.

Table 2. rabbitmq.properties content
Property name explanation

mailqueue.view.sliceWindow

James divides the view into slices, each slice contains data for a given period, sliceWindow parameter controls this period. This dividing of periods allows faster browsing of the mail queue. Tips for choosing sliceWindow are explained in rabbitmq.properties

mailqueue.view.bucketCount

Mails in a mail queue are distributed across the underlying storage service. BucketCount describes how to be distributing mails to fit with your James setup Tips for choosing bucketCount are explained in rabbitmq.properties

mailqueue.view.updateBrowseStartPace

To browse, James needs a starting point and to continuously update that point in runtime. UpdateBrowseStartPace describes the probability to update the starting point. Tips for choosing updateBrowseStartPace are explained in rabbitmq.properties

mailqueue.size.metricsEnabled

By default, the metrics are disabled for the mail queue size. As computing the size of the mail queue is currently implemented on top of browse operation and thus has a linear complexity, sometimes it can get too big, making it impossible for the ES reporter to handle it correctly without crashing. It can be useful then to disable it. Tips for choosing metricsEnabled are explained in rabbitmq.properties

RabbitMQ Tasks Configuration

Tasks are WebAdmin triggered long running jobs. RabbitMQ is used to organise their execution in a work queue, with an exclusive consumer.

Table 3. rabbitmq.properties content
Property name explanation

task.consumption.enabled

Whether to enable task consumption on this node. Disable with caution (this only makes sense in a distributed setup where other nodes consume tasks). Defaults to true.