Distributed James Server — Custom IMAP processing

James allows defining your own handler packages.

An Imap package is a simple class that bundles IMAP processing components:

public interface ImapPackage {
    Collection<ClassName> processors();

    Collection<ClassName> decoders();

    Collection<ClassName> encoders();
}

Processors needs to be of class AbstractProcessor, decoders of class AbstractImapCommandParser and encoders of class ImapResponseEncoder. Extensions-jar mechanism can be used to load custom classes.

Custom configuration can be obtained through ImapConfiguration class via the getCustomProperties method.

A full working example is available here.

See this page for more details on configuring IMAP extensions.

IMAP additional Connection Checks

James allows defining your own additional connection checks to guarantee that the connecting IP is secured.

A custom connection check should implement the following functional interface:

@FunctionalInterface
public interface ConnectionCheck {
    Publisher<Void> validate(InetSocketAddress remoteAddress);
}

  • validate method is used to check the connecting IP is secured.

Then the custom defined ConnectionCheck can be added in imapserver.xml file:

<additionalConnectionChecks>org.apache.james.CrowdsecImapConnectionCheck</additionalConnectionChecks>

An example for configuration is available here.