Cannot add objects on eagerly fetched associations

[mburak]

Having an association like this:

class Player extends AbstractGraphDomain {

    String name
    List<Club> formerClubs = []

    static hasMany = [formerClubs: Club]

    static mapping = {
        formerClubs lazy: false, fetch: "eager"
    }

}

when we try to add a new object to the association we get this:

java.lang.reflect.InvocationTargetException: null
        at org.grails.core.DefaultGrailsControllerClass$ReflectionInvoker.invoke(DefaultGrailsControllerClass.java:211)
        at org.grails.core.DefaultGrailsControllerClass.invoke(DefaultGrailsControllerClass.java:188)
        at org.grails.web.mapping.mvc.UrlMappingsInfoHandlerAdapter.handle(UrlMappingsInfoHandlerAdapter.groovy:90)
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
        at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55)
        at org.grails.web.servlet.mvc.GrailsWebRequestFilter.doFilterInternal(GrailsWebRequestFilter.java:77)
        at org.grails.web.filters.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:67)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.UnsupportedOperationException: null
        at java.util.AbstractList.add(AbstractList.java:148)
        at java.util.AbstractList.add(AbstractList.java:108)
        at org.grails.datastore.mapping.dirty.checking.DirtyCheckingCollection.add(DirtyCheckingCollection.groovy:52)
        at org.grails.datastore.gorm.neo4j.collection.Neo4jList.add(Neo4jList.groovy:59)
        at org.sampleapp.core.PlayerController.$tt__updatePlayer4(PlayerController.groovy:68)
        at grails.transaction.GrailsTransactionTemplate$2.doInTransaction(GrailsTransactionTemplate.groovy:96)
        at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133)
        at grails.transaction.GrailsTransactionTemplate.execute(GrailsTransactionTemplate.groovy:93)
        ... 14 common frames omitted

You can reproduce this by downloading the project at https://github.com/mburak/sampleapp and checking out branch called 'assoc-error'.
#1. Start the project on an empty db
#2. Do an ajax call to http://localhost:8080/player/updatePlayer4

[jameskleeh]

@mburak When I run your example application with an embedded neo4j, I get org.neo4j.driver.v1.exceptions.ClientException: Unable to convert org.sampleapp.core.Club to Neo4j Value.

Edit: That was because the club assocation on Player was commented out

[jameskleeh]

@mburak I'm unable to reproduce the issue because the URL you indicated to execute returns 404. There are no controllers in the example application