Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
Regarding bug 1426046 (see below) -- Is this just a matter of making the classes public or are you thinking the driver interface needs more thought + solidifying before making something extendable? Perhaps I can donate a cycle to 2 to help get this in. On 2/26/15 10:33 AM, Doug Hellmann wrote: Yes, I don't recommend relying on anything in private modules. It looks like even the base class for the notification drivers is private, right now. We should probably change that, so I filed https://bugs.launchpad.net/oslo.messaging/+bug/1426046. __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
On Thu, Feb 26, 2015, at 07:24 AM, Boden Russell wrote: What's the suggested approach for implementing a custom oslo messaging driver given the existing impl [1] is private? e.g. I want to provide my own notification messaging driver which adds functionality atop the existing driver [1]. This can obviously be done by extending the oslo.messaging.notify._impl_messaging.MessagingDriver and registering the custom impl as a stevedore plugin. e.g. --- from oslo.messaging.notify import _impl_messaging as messaging class MyMessagingDriver(messaging.MessagingDriver): # impl below --- This works, but given the private nature of oslo's _impl_messaging I'm likely not following best practices. Any feedback is appreciated. Yes, I don't recommend relying on anything in private modules. It looks like even the base class for the notification drivers is private, right now. We should probably change that, so I filed https://bugs.launchpad.net/oslo.messaging/+bug/1426046. Maybe if you can give more details about what your driver wants to do, I can provide better feedback about a short-term approach for you. Doug Thanks [1] http://goo.gl/cRGNwJ __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
I don't have a public repo -- have been PoCing using a private gitlab to date... I figured any interest in the driver impl would come out of this email discussion. More than happy to provide my PoC code publicly (after a little clean-up) if there's an interest. On 2/26/15 12:01 PM, Sandy Walsh wrote: Cool, I'm interested in creating some notification drivers outside of olso-messaging as well (for Kafka support and schema-based notifications). Do you have a repo started on this? I'd be keen to have a look. __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
Cool, I'm interested in creating some notification drivers outside of olso-messaging as well (for Kafka support and schema-based notifications). Do you have a repo started on this? I'd be keen to have a look. -S From: Boden Russell boden...@gmail.com Sent: Thursday, February 26, 2015 2:41 PM To: OpenStack Development Mailing List (not for usage questions) Subject: Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver Thanks for filing the bug report... My driver implementation effectively allows you to filter on notification events and multicast matches to a given list of topics. I've been calling it an messaging multicast notification driver and thus the plugin stevedore entry point I've called 'messaging-multicast'. The impl basically wraps the oslo messaging driver and does it's matching and multicasting after the parent... e.g. def notify(self, ctxt, msg, priority, retry): _notify = super(AMQPMulticastDriver, self).notify( ctxt, msg, priority, retry) # check filters on msg and priority and notify on configured topics # for any matches below ... code ... return _notify The driver is a drop-in replacement anywhere oslo.messaging is used for notifications and accepts some conf props to set it up. example config for usage (glance in this example): rpc_backend = rabbit ... notification_driver = messaging-multicast multicast_events = image.upload,image.delete multicast_topic_prefix = glance.multicast. publisher_id = GLANCE:MASTER image.delete = host1,host2 image.upload = host1,host2 The above will send a copy of image.delete and image.upload events to the glance.multicast.host1 and glance.multicast.host2 topics. It will use 'GLANCE:MASTER' as the publisher ID in the multicasted events. Your feedback is appreciated. On Thu, Feb 26, 2015, at 07:24 AM, Boden Russell wrote: What's the suggested approach for implementing a custom oslo messaging driver given the existing impl [1] is private? [1] http://goo.gl/cRGNwJ On 2/26/15 10:33 AM, Doug Hellmann wrote: Yes, I don't recommend relying on anything in private modules. It looks like even the base class for the notification drivers is private, right now. We should probably change that, so I filed https://bugs.launchpad.net/oslo.messaging/+bug/1426046. Maybe if you can give more details about what your driver wants to do, I can provide better feedback about a short-term approach for you. __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
Thanks for filing the bug report... My driver implementation effectively allows you to filter on notification events and multicast matches to a given list of topics. I've been calling it an messaging multicast notification driver and thus the plugin stevedore entry point I've called 'messaging-multicast'. The impl basically wraps the oslo messaging driver and does it's matching and multicasting after the parent... e.g. def notify(self, ctxt, msg, priority, retry): _notify = super(AMQPMulticastDriver, self).notify( ctxt, msg, priority, retry) # check filters on msg and priority and notify on configured topics # for any matches below ... code ... return _notify The driver is a drop-in replacement anywhere oslo.messaging is used for notifications and accepts some conf props to set it up. example config for usage (glance in this example): rpc_backend = rabbit ... notification_driver = messaging-multicast multicast_events = image.upload,image.delete multicast_topic_prefix = glance.multicast. publisher_id = GLANCE:MASTER image.delete = host1,host2 image.upload = host1,host2 The above will send a copy of image.delete and image.upload events to the glance.multicast.host1 and glance.multicast.host2 topics. It will use 'GLANCE:MASTER' as the publisher ID in the multicasted events. Your feedback is appreciated. On Thu, Feb 26, 2015, at 07:24 AM, Boden Russell wrote: What's the suggested approach for implementing a custom oslo messaging driver given the existing impl [1] is private? [1] http://goo.gl/cRGNwJ On 2/26/15 10:33 AM, Doug Hellmann wrote: Yes, I don't recommend relying on anything in private modules. It looks like even the base class for the notification drivers is private, right now. We should probably change that, so I filed https://bugs.launchpad.net/oslo.messaging/+bug/1426046. Maybe if you can give more details about what your driver wants to do, I can provide better feedback about a short-term approach for you. __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] [oslo.messaging] extending notification MessagingDriver
On Thu, Feb 26, 2015, at 01:41 PM, Boden Russell wrote: Thanks for filing the bug report... My driver implementation effectively allows you to filter on notification events and multicast matches to a given list of topics. I've been calling it an messaging multicast notification driver and thus the plugin stevedore entry point I've called 'messaging-multicast'. The impl basically wraps the oslo messaging driver and does it's matching and multicasting after the parent... e.g. def notify(self, ctxt, msg, priority, retry): _notify = super(AMQPMulticastDriver, self).notify( ctxt, msg, priority, retry) # check filters on msg and priority and notify on configured topics # for any matches below ... code ... return _notify The driver is a drop-in replacement anywhere oslo.messaging is used for notifications and accepts some conf props to set it up. The notification drivers config option supports multiple values, so you don't need to subclass in order to make that work. You could implement a completely separate driver that does different notifications than the built-in version. Of course, we should probably make that base class public but you don't have to actually subclass it for your driver to work AFAICT. You might also want to look at the existing RoutingDriver. It does not do quite what you want, but some of the concepts might be useful. It would be useful to be able to compose the routing notifier with other notifiers to do the sort of thing you're talking about without having to build a custom driver. example config for usage (glance in this example): rpc_backend = rabbit ... notification_driver = messaging-multicast multicast_events = image.upload,image.delete multicast_topic_prefix = glance.multicast. publisher_id = GLANCE:MASTER image.delete = host1,host2 image.upload = host1,host2 The above will send a copy of image.delete and image.upload events to the glance.multicast.host1 and glance.multicast.host2 topics. It will use 'GLANCE:MASTER' as the publisher ID in the multicasted events. Your feedback is appreciated. On Thu, Feb 26, 2015, at 07:24 AM, Boden Russell wrote: What's the suggested approach for implementing a custom oslo messaging driver given the existing impl [1] is private? [1] http://goo.gl/cRGNwJ On 2/26/15 10:33 AM, Doug Hellmann wrote: Yes, I don't recommend relying on anything in private modules. It looks like even the base class for the notification drivers is private, right now. We should probably change that, so I filed https://bugs.launchpad.net/oslo.messaging/+bug/1426046. Maybe if you can give more details about what your driver wants to do, I can provide better feedback about a short-term approach for you. __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
[openstack-dev] [oslo.messaging] extending notification MessagingDriver
What's the suggested approach for implementing a custom oslo messaging driver given the existing impl [1] is private? e.g. I want to provide my own notification messaging driver which adds functionality atop the existing driver [1]. This can obviously be done by extending the oslo.messaging.notify._impl_messaging.MessagingDriver and registering the custom impl as a stevedore plugin. e.g. --- from oslo.messaging.notify import _impl_messaging as messaging class MyMessagingDriver(messaging.MessagingDriver): # impl below --- This works, but given the private nature of oslo's _impl_messaging I'm likely not following best practices. Any feedback is appreciated. Thanks [1] http://goo.gl/cRGNwJ __ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
