On Mon, Jun 24, 2013 at 4:02 AM, Ian Boston <i...@tfd.co.uk> wrote: > Hi Dishara, > Yes. 1 resource == 1 row. > The columns within that row represent the properties of the resource. > I suggest that you use standard property names where appropriate (eg > sling:resourceType is the Resource.resourceType etc) > > The Resource itself should be adaptable to a generic CassandraResource > (which will probably implement Resource) which will have a map of > properties containing all the columns of the cassandra row. (optimise > later) A CassandraResource might look and feel like a Map<String, Object> > or it might have a Map<String, Object> getProperties() method, or better > still be adaptable to a Map. The essential think is dont hard code the > property names in the interface of CassandraResource for the moment. ie no > getContentType() and no getMimeType(), as we dont really know what a > CassandraResource will store. > > ResourceMetadata should be built from a subset of the CassandraResource > properties. > > You won't need to implement a ResourceResolver, only a ResourceProvider > (and Factory). I would use CQL in preference to other API methods. > > There is one thing that hasnt been mentioned, and thats the URL -> > Cassandra Row mapping. > There are several ways of doing this. > > eg: > URL = /content/cassandra/<columnFamily>/<rowID> > Cassandra Column Family = columnFamily > Cassandra RowID = rowID > or > URL = /content/cassandra/<columnFamilySelector>/remainder/of/the/path > Cassandra Cassandra Column Family = > mapOfColumnFamilies.get(columnFamilySelector) > Cassandra RowID = function(/remainder/of/the/path) > > or to take that one stage further > > public interface CassandraMapper { > String getCQL(String columnFamilySelector, String path); > } > Hi Ian Thank you for the detailed explanation.
OK. +1 for this approach with the mentioned flexibility.But I need a small clarification. With this approach, URL = /content/cassandra/<columnFamilySelector>ROW-ID ROW-ID - function(/remainder/of/the/path). So you mean ROW-ID is something we have to programatically uniquely create right ? like a UUID. What is this "/remainder/of/the/path" means ? Can you give an example with real values in the context of a user who want to obtain a resource from cassandra. This is just for my understanding. > > URL = /content/cassandra/<columnFamilySelector>/<remainderOfPath> > > String cqlQuery = > > mapOfCassandraMappers.get(columnFamilySelector).getCQL(columnFamilySelector, > remainderOfPath); > > Which would allow us provided one or more implementations of > CassandraMapper to map between URL and CQL. > > > HTH > Ian > > > > > > > > > > > > > > > > > On 23 June 2013 19:29, Dishara Wijewardana <ddwijeward...@gmail.com> > wrote: > > > Hi Ian, > > > > What is the data mapping should be between Cassandra and Sling resource. > I > > mean is a Sling Resource maps to a Cassandra Column ? Or Column Family ? > > > > Because to get this Cassandra and Sling story correct we need to finalize > > this. > > For an example what we eventually returns is a Sling resource. Everything > > that needs to fill in to create Sling resource should be stored in > > Cassandra. > > In a Sling resource, > > > > - Path - direct sling resource path > > - ResourceType - nt:cassandra > > - ResourceSuperType - ? > > - ResourceMetadata - we can create this on the fly with the data from > > the corresponding column. At insertion, those need to be stored. > > Following > > are the ones which I thought might be useful by default to be set for > > any > > node. Please add if we need anything more. > > - ContentType > > - ContentLength > > - CreationTime > > - ModificationTime > > - ResourceResolver - Do we need a resolver in this case ? > > > > > > So I believe in CQL context, one ROW should represent a Sling resource. > If > > that is the case for ResourceMetadata we might need a separate column to > > store it since it has multiple values. I am not sure whether we can do it > > with CQL, but it should be possible with hector APIs may be. > > > > Appreciate your thoughts ? > > > > > > On Wed, Jun 19, 2013 at 1:19 AM, Dishara Wijewardana < > > ddwijeward...@gmail.com> wrote: > > > > > Hi Ian, > > > I am starting this thread to keep track on things related to the GSoC > > > project related milestone status updates and related discussions. > > > So the first task over view will be as follows as per GSoC proposal > > > provided. > > > > > > 1. Implementing a CassandraResourceProvider to READ from Cassandra. > > > Implementation Details [1] > > > > > > > > > > > > [1] : Implementation Details: > > > > > > 1.A) Write a CassanrdaResourceProviderUtil which is basically a > > > cassendra client which will facilitate all cassandra related operations > > > required by other modules (CassandraResourceProvider and > > > CassandraResourceResolver). > > > > > > 1.B) Implementation of CassandraResourceProvider > > > > > > 1.C) Implementation of CassandraResourceResolver > > > > > > 1.D) Implementation of CassandraResource > > > > > > > > > And I will start writing the CassanrdaResourceProviderUtil class which > > > will do basic add and get using hector API. Please provide any feedback > > > that will be useful to accomplish this task. > > > So for this how does path mapping should be done. Because for example, > > the > > > path of the cassendra node will not be same as the jcr node path. i.e > > > provider will ask a node path /system/myapps/test/foo and where should > we > > > return it from Cassandra. Aren't we have to first consider the WRITE > > aspect > > > to Cassandra ? > > > > > > > > > -- > > > Thanks > > > /Dishara > > > > > > > > > > > -- > > Thanks > > /Dishara > > > -- Thanks /Dishara