Aggregation Strategies
Chimera provides Camel Aggregation Strategies for combining data from multiple routes before processing. These are used with Camel's aggregate, multicast, or split EIPs.
GraphAggregation
Package: com.cefriel.component.GraphAggregation
Merges two RDFGraph repositories. All triples from the new exchange's graph are copied into the old exchange's graph.
Use this when splitting or multicasting work across multiple graph operations and then recombining the results.
from("direct:merge")
.aggregate(constant(true), new GraphAggregation())
.completionSize(2)
.to("graph://dump?dumpFormat=turtle");
ReadersAggregation
Package: com.cefriel.aggregationStrategy.ReadersAggregation
Accumulates a Map<String, Reader> from multiple routes. Each contributing exchange must set two exchange variables:
| Variable | Description |
|---|---|
readerFormat |
Reader type: csv, json, xml, rdf, or sql. |
readerName |
Key for this reader in the resulting map. |
For rdf readers, an additional variable readerInputFile (file name with extension) is used to determine the RDF format. Alternatively, sparqlEndpoint can be set to create an RDF reader backed by a SPARQL endpoint.
For sql readers, the exchange body must be a JdbcConnectionDetails object, or the variables jdbcDSN, username, and password must be set.
The resulting Map<String, Reader> is used with mapt://readers.
See mapt://readers for a full example.
TemplateAggregation
Package: com.cefriel.aggregationStrategy.TemplateAggregation
Aggregates a template InputStream from a new exchange into the old exchange's property MaptTemplateConstants.TEMPLATE_STREAM. Use this when the Velocity template itself is produced dynamically by an upstream route.
KeyValuePairsAggregation
Package: com.cefriel.aggregationStrategy.KeyValuePairsAggregation
Aggregates a key-value pairs InputStream into the old exchange's property MaptTemplateConstants.KEY_VALUE_PAIRS. Use this when the properties file for keyValuePairs is produced by an upstream route.
KeyValueCSVAggregation
Package: com.cefriel.aggregationStrategy.KeyValueCSVAggregation
Aggregates a CSV key-value InputStream into the old exchange's property MaptTemplateConstants.KEY_VALUE_CSV. Use this when the CSV file for keyValuePairsCSV is produced by an upstream route.
QueryFilePathAggregation
Package: com.cefriel.aggregationStrategy.QueryFilePathAggregation
Aggregates a query file InputStream into the old exchange's property MaptTemplateConstants.QUERY_FILE. Use this when the SPARQL query file for parametric mappings is produced by an upstream route.