We will try to get some architecture docs posted shortly, however, in the mean time, I can answer some of your specific questions.

Tenancy and isolation is handled in two different areas, there is isolation in the DEA (dropplet execution agent) which runs your actual code, and in there is isolation in the services.  The DEA runs every app as a separate locked down user with reduced privileges and utilizes standard unix/linux security isolation mechanisms.  The services each handle multi-tenancy in a way that is appropriate to the service.  For example, the mysql service uses a single process per mysql node, but when we provision a database for a user/app, we generate unique credentials for that user/app and only grant access to the newly provisioned database to that newly provisioned user/app.  Other services like mongodb create a new mongodb process per provisioning request (with a randomly generated admin user and credentials) in order to perform multi-tenant isolation.

As for how to create a new service, we will be publishing a services api document soon, but in the mean time, you can take a look at https://github.com/cloudfoundry/vcap-services/blob/master/common/as....  The parts you would want to implement are the sinatra handlers, as the reset is specific to the AC implementation of services, i.e.:

 post '/gateway/v1/configurations' do

delete '/gateway/v1/configurations/:service_id' do

 post '/gateway/v1/configurations/:service_id/handles' do

delete '/gateway/v1/configurations/:service_id/handles/:handle_id' do

Plus the common auth handling and validation done in the sinatra handler: 

before do

You can also implement services at a slightly higher level of abstraction, however, this functionality was a bit in flux just prior to launch and will have some changes coming soon.  For some examples to follow as a guide, look at the mongodb service implementation.  It's service gateway and node implementations each use a standard base class to ease implementation, but again, this is going to go through some changes over the next few weeks.

Anyway, hopefully that is enough to get you started.  Look for some real docs and improved guidance in this space in the near future.

Thanks

Great, thanks a lot.

This gives me some basic understanding. I am looking forward to the docs.

Bernd

Hello, Patrick,

  Looking forward to the architecture-related docs very much!

  Thanks a lot!

In addition,

> Bernd

I also  found  some material from Internet, and I feel them excellent!

①”VMware CloudFoundry: Ruby powered PaaS”
http://www.igvita.com/2011/04/14/vmware-cloudfoundry-ruby-powered-paas/

②”Cloud Foundry Architecture and Auto-Scaling”
http://blog.rightscale.com/2011/04/14/cloud-foundry-architecture-and-auto-scaling/
---Tang

Some in the Eclipse Virgo community are interested in adding a DEA. Any hints on how you intend that to be done would be great.

Actually, perhaps this is slightly off-topic for this thread, so I'll start a fresh thread.

... here: http://support.cloudfoundry.com/entries/20034556-how-to-add-a-new-dea

How cloud foundry is different then tomcat tc server?

http://virtualization-for-layman.blogspot.com/2011/05/vmware-cloudf...