I'll reply myself. As seen on the code JdbcCamelCodec doesn't allow to save properties when backing the Aggregator with a database:
public final class JdbcCamelCodec {
public byte[] marshallExchange(CamelContext camelContext, Exchange exchange) throws IOException {
// use DefaultExchangeHolder to marshal to a serialized object
DefaultExchangeHolder pe = DefaultExchangeHolder.marshal(exchange, false);
// add the aggregated size property as the only property we want to retain
DefaultExchangeHolder.addProperty(pe, Exchange.AGGREGATED_SIZE, exchange.getProperty(Exchange.AGGREGATED_SIZE, Integer.class));
// add the aggregated completed by property to retain
DefaultExchangeHolder.addProperty(pe, Exchange.AGGREGATED_COMPLETED_BY, exchange.getProperty(Exchange.AGGREGATED_COMPLETED_BY, String.class));
// add the aggregated correlation key property to retain
DefaultExchangeHolder.addProperty(pe, Exchange.AGGREGATED_CORRELATION_KEY, exchange.getProperty(Exchange.AGGREGATED_CORRELATION_KEY, String.class));
// persist the from endpoint as well
if (exchange.getFromEndpoint() != null) {
DefaultExchangeHolder.addProperty(pe, "CamelAggregatedFromEndpoint", exchange.getFromEndpoint().getEndpointUri());
}
return encode(pe);
}
Basically, the problem lies on this line where false means: don't save properties.
DefaultExchangeHolder pe = DefaultExchangeHolder.marshal(exchange, false);
The headers and the body are the only ones stored on database.