Hello Ivo, First of all, I'm not sure what your e-mail app is doing to the quoted text, but it's coming out all garbled here.
On Jan 27, 2012, at 13:34 PM, Ivo Ladage-van Doorn wrote: > I thought the WIKI page > http://www.amdatu.org/confluence/display/Amdatu/Amdatu+Core+Tenant+Use+Cases > described the use cases that the platform is going to support. If you say > "it's up to the application to implement it", the platform must by design > support it and be able to tell me how to implement it. If the answer is that > that is not the concern of the platform, that's the same as saying you do not > support these use cases. The platform implements and therefore supports those use cases. Jan Willem already replied with a proposal to send out events whenever tenants get created or destroyed. That will allow you to create and destroy your keyspace (by subscribing to those events). > I think the following Use Cases are crucial for using Amdatu in combination > with Cassandra: > > Use case 5 (MT-UC5): > As a developer, I want to be able to add/remove tenants on the go. >> Indeed, using Cassandra I want to create a new keyspace and associate it >> with a new tenant and delete the tenant when it is deleted. See above. > Use case 9 (MT-UC9): > As a developer, I want to be able to purge all platform-specific data of a > (former) tenant without other influencing other tenants. >> Yes, upon a purge I will delete the keyspace See above. > Use case 10 (MT-UC10): > As a developer, I want to be able to migrate a tenant from one container to > another >> In a Cassandra cluster there is no way you can have a different set of >> keyspaces per node. You could have several clusters though, but a single >> Cassandra node cannot join multiple clusters. In a Cassandra cluster the >> data being stored is also not really associated with a physical machine; >> it's out somewhere but it's up to Cassandra to decide where to store it >> (even data in a single keyspace may distributed over several nodes). So this >> use case doesn't make sense with Cassandra. > However, if you're talking about data isolation and Cassandra, you should be > able to define multiple Cassandra clusters, such that data within one cluster > is 'isolated' from the other clusters. So the use case should be; " As a > developer, I want to be able to migrate a tenant from one cluster to another". The platform does not have the notion of a cluster. We know about containers, and (looking ahead at provisioning support in the platform) we decided to add this use case: For normal bundles, if we take a bundle and its data area, and install it in a new container, it will keep its state. We wanted to make sure the experience is the same for tenant aware bundles. If moving that data area is enough for Cassandra to migrate data from one cluster to the other, great. If not, you need to work on a solution yourself. > Use case 11 (MT-UC11): > As a developer, I want to implement services that can be notified in case a > tenant is created or destroyed. >> If with 'destroyed' you mean 'deleted', then this is exactly what I need. Yes, see above, destroyed is deleted. Greetings, Marcel _______________________________________________ Amdatu-developers mailing list [email protected] http://lists.amdatu.org/mailman/listinfo/amdatu-developers
