BlockHound finds blocking call on projection

[bekirtaskin]

BlockHound finds projection is "blocking call";

I am using ReactiveNeo4jRepository with cypher query;

Spring data tries to read return class and gets blocking call exception.

I have tried this Spring boot 2.5.6 WebFlux and spring-data-neo4j 6.1.6
I have created a test project on Github to demonstrate. https://github.com/bekirtaskin/spring-data-neo4j-blockhound

Spring data reads classes for only one time, I think it can be added to whitelist but I am not sure.

[mp911de]

Thanks for the report. Spring Data's projection infrastructure indeed parses ASM metadata by reading class files to analyze the projection. Projections can be declared as concrete projection return types but also be dynamic (<T> T findBy(…, Class<T>) and that is why we analyze the return type during query creation/result processing.

While we could move the parsing of static projections to an earlier phase, we still would not be able to solve the underlying issue of dynamic projections. For the time being, please exclude the code path from BlockHound.