Yes. One could implement DBLoader interface and provide that as a plugin to Enrichment Operator during compile time.
On Tue, Mar 15, 2016 at 7:17 PM, Mohit Jotwani <[email protected]> wrote: > This is one of the most important features required within a pipeline. > > Will it allow other store plugins (for reference lookup) to be added to the > operator? > > +1 > > Regards, > Mohit > > On Tue, Mar 15, 2016 at 6:57 PM, Chinmay Kolhatkar <[email protected]> > wrote: > > > Hello Community, > > > > We want to add Enrichment operator to malhar library. > > > > Here are some initial details about it: > > > > UseCase: > > ================= > > Data enrichment is an extremely common and important step in almost ALL > > batch and stream processing flows. > > Streaming use cases deal with log data which often lacks context and > > metadata. The metadata is required for all additional analytical > processing > > This operator allows one to enrich stream data with data from external > > source. > > > > Functionality: > > ================= > > 1. Take input as POJO and emit enriched POJO as per the configuration. > > 2. The external store can be configurable and will be a plugin model. > > 3. Currently support for JDBC, Hbase and File based format store will be > > added. > > 4. Operator will perform a reference lookup to these external databases > to > > enrich the incoming tuple. > > > > Design: > > ================= > > 1. As mentioned above stores (viz. Database Loaders) will be plugin based > > machanism. > > 2. To make the loaders pluggable they'll follow a common interface as > > follows: > > public interface DBLoader extends > > com.datatorrent.lib.db.cache.CacheManager.Backup > > { > > public void setFields(List<String> lookupFields,List<String> > > includeFields); > > public void setFieldInfo(List<FieldInfo> fieldInfos) > > } > > 3. All the above mentioned loaders (JDBC, Hbase, file etc) will implement > > above interface and Enrichment Operator will use object of this interface > > to query missing fields to be enriched. > > 4. Both input and output ports of Enrichment Operator will need to be set > > with TUPLE_CLASS Attribute for the operator to know of upstream and > > downstream. > > This means, input schema can be seperate from output schema. > > 5. Enrichment operator will use PojoUtils to create getters and setters > > which will be used to dynamically generate the new enriched object on the > > fly. > > 6. User need to configure enrichmentMap for any change in > > columnName/inputFieldName to outputField. > > > > Please provide your valuable feedback on above. > > > > Thanks in advance, > > Chinmay. > > >
