INT-3333: Return empty list as is from DB gateway #3907
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garyrussell
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Oct 11, 2022
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| Starting with the version 6.0, the `JdbcOutboundGateway` returns an empty list result as is instead of converting it to `null` as it was before with the meaning "no reply". | ||
| This caused an extra configuration in applications where handling of empty lists is a part of downstream logic. | ||
| See <<./splitter.adoc#split-stream-and-flux,Splitter Discard Channel>> for possible empty list handling option. |
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| Starting with the version 6.0, the `JdbcOutboundGateway` returns an empty list result as is instead of converting it to `null` as it was before with the meaning "no reply". | |
| This caused an extra configuration in applications where handling of empty lists is a part of downstream logic. | |
| See <<./splitter.adoc#split-stream-and-flux,Splitter Discard Channel>> for possible empty list handling option. | |
| Starting with the version 6.0, the `JdbcOutboundGateway` returns an empty list result when there are no records returned by the query. | |
| Previously, `null` was returned, ending the flow, or throwing an exception, depending on `requiresReply`. | |
| This required extra configuration in applications where handling of empty lists is part of the downstream logic. | |
| See <<./splitter.adoc#split-stream-and-flux,Splitter Discard Channel>> for possible empty list handling options. | |
| Or, to revert to the previous behavior, add a `filter` after the gateway to filter out empty lists. |
Fixes https://jira.spring.io/browse/INT-3333 In `JdbcOutboundGateway` and `JpaOutboundGateway` the empty result list is treated as "no reply" and therefore `null` is returned cause the flow to stop at this point. It is better to return such a result as is and the target application to decided what to do with it, e.g. a `discardChannel` on a downstream splitter configuration. NOTE: the `MongoDbOutboundGateway` doesn't treat an empty result as a `null`
Co-authored-by: Gary Russell <[email protected]>
garyrussell
approved these changes
Oct 11, 2022
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Fixes https://jira.spring.io/browse/INT-3333
In
JdbcOutboundGatewayandJpaOutboundGatewaythe empty result list is treated as "no reply" and thereforenullis returned cause the flow to stop at this point.It is better to return such a result as is and the target application to decided what to do with it, e.g. a
discardChannelon a downstream splitter configuration.NOTE: the
MongoDbOutboundGatewaydoesn't treat an empty result as anull