com.neeve.toa.spi
Interface ChannelQosProvider

public interface ChannelQosProvider

A ChannelQosProvider resolves the channel filter for a given ToaServiceChannel channel.

Channel QoS Resolution in Hornet

A TopicOrientedApplication in hornet will automatically create buses and channels that have have not already been configured for the application.

In the absense of a ChannelQosProvider:

• If the bus and channel is defined already in DDL the configured QoS will be used as the default.
• If the channel is not defined then QoS default is set to Guaranteed

ChannelQosProviders can be used to override the QoS determined above:

• If any ChannelQosProviders returns a MessageChannel.Qos via getChannelQos(ToaService, ToaServiceChannel) that value is used to update the MessageChannel.Qos for the channel.
• If one provider returns `BestEffort` and another `Guaranteed`, then Guaranteed is chosen.

The above logic only applies to channels discovered in Hornet services. Any preconfigured channels for a bus that are unrelated to a service for the application are not modified.

See Also:

TopicOrientedApplication messaging configuration

Method Summary

MessageChannel.Qos

getChannelQos(ToaService service, ToaServiceChannel channel) Returns the channel MessageChannel.Qos for the given ToaServiceChannel.

Method Detail

getChannelQos

MessageChannel.Qos getChannelQos(ToaService service,
                                 ToaServiceChannel channel)

Returns the channel MessageChannel.Qos for the given ToaServiceChannel.

If multiple ChannelQosProviders return differing MessageChannel.Qos values for the same service and channel the highest quality of service will be selected (e.g. Guaranteeed).

Parameters:

service - The service that defined the channel.

channel - The channel.

Returns:

The channel MessageChannel.Qos or null if the provider either doesn't provide MessageChannel.Qos for this channel or if the channel should not be filtered.

See Also:

TopicOrientedApplication messaging configuration