Support additional backends

It would be pretty great if this had a backend that could read from Apache Mesos (or alternatively, Marathon) in addition to consul. There's a great project in the space called Traefik which will do HTTP in a very similar fashion but the only solutions I've seen for straight TCP have revolved around scripted HAProxy which is pretty ugly.

[magiconair]

Additional backends is something I'm considering but I want to do some other things first.

If you need any testing done let me know!

[magiconair]

I'm going to take a first step in this direction by refactoring the code to hide the consul specific logic behind an interface. This will make supporting additional backends simpler.

However, my main concern is whether these systems (e.g. Marathon) allow services to publish their routes in the registry (e.g. zookeeper or etcd) in an atomic way. The purpose of fabio is to be stateless and build the routing table automatically and not just to use a different storage mechanism.

[magiconair]

Support for Google Compute Platform is in the works by @emicklei

[composer22]

I'd request one for the docker/swarm API. This would eliminate consul and registrator background containers completely.

Docker API allows you to query networks (incl overlay network) for running containers. You can use this to extract running services and IP addresses. Another interesting resource, with overlay networks and custom bridge networks in Docker, you get a /etc/host file in every running container which points to other running containers in the network(s). If a container is stopped or destroyed, it is pulled from the host file by docker automatically. This could also be used to wire up services.

Containers can be run in multiple custom networks, hence one Fabio instance could be a service point for consolidating needs.

The metadata that is attached to a container which propogates via registrator to Consul could still be used to create services in Fabio with no change IMHO. Hence current config patterns should not be affected except they would need to be started or join a network the Fabio instance is sharing.

[magiconair]

@composer22 How does fabio get notified of changes in the swarm setup? Polling? Other than that it looks interesting.

[Kosta-Github]

You can hook into the docker events via this HTTP endpoint: https://docs.docker.com/engine/reference/api/docker_remote_api_v1.21/#monitor-docker-s-events

It looks like the anchor is not positioning the page correctly, so you probably have the search for "monitor docker's events"...

[composer22]

@magiconair @Kosta-Github

Yes, monitoring events √

Loot at the package:

https://github.com/fsouza/go-dockerclient

and I think this particularly:

https://godoc.org/github.com/fsouza/go-dockerclient#Client.AddEventListener

I'm performing some EXP work on the API usage. Not sure how it would evolve with an enhancement to Fabio.

Here are some thoughts.

• Fabio will need to perform it's own health checks instead of Consul. Not sure fabio is performing these now.
• Create Facade objects within Fabio that appear to resemble Consul service objects in memory and let Fabio go to town on these. This will allow for a common interface to both providers.

[magiconair]

Fabio performing health checks does not sound like a direction I want to go. Fabio is only a client of a service registry. Something else needs to maintain the state.