The partition-by-prefix feature can be configured with gfsh, cache.xml, or apis.
We did not want it to be configured as a PartitionResolver because that ends up with overly verbose configuration. You end up with something like: gfsh create region "foo" --partition-resolver=org.apache.geode.resolvers.PartitionByPrefix.class instead of: gfsh create region "foo" --partition-by-prefix=true The reason for two configuration attributes (a boolean to enable the feature, and a string to customize the default delimiter) was for clarity. We thought that most use cases would just use the boolean and set it to true because they could use the default delimiter. The configuration of the delimiter is only needed when your existing prefix string contains the default delimiter. If we have just one configuration attribute (the delimiter) then it needs to default to the empty string which means the feature is disabled. I originally was pushing for the single configuration attribute but was convinced by others that the two config attribute was better. I like the idea of geode having a predefined delimiter like ":" instead of it always needed to be configured if you are going to use it. But since the customer has to always add this delimiter to their string keys perhaps it is better for them to have to explicitly configure what it is. I do not like the idea of returning the entire key if no delimiter is found. This seems error prone. If a developer forgets to put the correct delimiter in a key I think it is better for it to fail fast then to just instead use the default hash of the entire key. In the example of a Customer and Customer.Orders region you would just use the normal "partition-by-key" policy on the Customer region and then configure "partition-by-prefix" on the Customer.Orders region. You have no need for both regions to be configured with "partition-by-prefix". If someone does want to have a mix of keys, some with prefixes and some without, on the same region then they could just implement their own PartitionResolver and have it support this mix. I don't see that "partition-by-prefix" needs to support this use case unless it is very common. On Wed, May 31, 2017 at 10:15 AM, Michael Stolz <mst...@pivotal.io> wrote: > I don't really see a need for new Region api for this except to be able to > specify the delimeter. > > A developer can just specify the provided PartionByPrefix class for his > PartitionResolver during region creation? > > Providing a String key with no delimiter should just return the entire key, > NOT throw an error. That way the same PartitionResolver can be used for > both the Customer region and the Customer.Orders region and it just works. > > One more thing, we need to be able to specify a partition resolver via > gfsh. > > -- > Mike Stolz > Principal Engineer - Gemfire Product Manager > Mobile: 631-835-4771 <(631)%20835-4771> > > On May 30, 2017 3:26 PM, "Fred Krone (JIRA)" <j...@apache.org> wrote: > > > > > [ https://issues.apache.org/jira/browse/GEODE-3005?page=com.at > > lassian.jira.plugin.system.issuetabpanels:all-tabpanel ] > > > > Fred Krone updated GEODE-3005: > > ------------------------------ > > Description: > > A user should be able to set partition by prefix programmatically when > > creating a partitioned region. > > > > This can only be done when creating a Region type PARTITION > > > > Acceptance: > > Partitioned region can be created using new 'partition by prefix' > > attributes (on/off, delimiter) > > Only String keys work -- all other keys throw an error > > Providing a key with the correct delimiter routes the entry to the > correct > > node > > Providing a key with no delimiter throws an error > > > > > > was: > > A user should be able to set partition by prefix programmatically when > > creating a partitioned region. > > > > This can only be done when creating a Region type PARTITION > > > > > > > A developer can create a Region with Partition Resolution using Java > API > > > ------------------------------------------------------------ > ------------ > > > > > > Key: GEODE-3005 > > > URL: https://issues.apache.org/jira/browse/GEODE-3005 > > > Project: Geode > > > Issue Type: Wish > > > Components: regions > > > Reporter: Fred Krone > > > Assignee: Fred Krone > > > > > > A user should be able to set partition by prefix programmatically when > > creating a partitioned region. > > > This can only be done when creating a Region type PARTITION > > > Acceptance: > > > Partitioned region can be created using new 'partition by prefix' > > attributes (on/off, delimiter) > > > Only String keys work -- all other keys throw an error > > > Providing a key with the correct delimiter routes the entry to the > > correct node > > > Providing a key with no delimiter throws an error > > > > > > > > -- > > This message was sent by Atlassian JIRA > > (v6.3.15#6346) > > >
