JSON view error after upgrading from 3.1.11 to 3.2.0

Question

I recently upgraded my 3.1.11 app to Grails 3.2.0 app and call to an endpoint started failing for some reason with the follwoing stacktrace:

ERROR org.grails.web.errors.GrailsExceptionResolver - StackOverflowError occurred when processing request: [GET] /api/application
Stacktrace follows:
java.lang.reflect.InvocationTargetException: null
    at org.grails.core.DefaultGrailsControllerClass$ReflectionInvoker.invoke(DefaultGrailsControllerClass.java:210)
    at org.grails.core.DefaultGrailsControllerClass.invoke(DefaultGrailsControllerClass.java:187)
    at org.grails.web.mapping.mvc.UrlMappingsInfoHandlerAdapter.handle(UrlMappingsInfoHandlerAdapter.groovy:90)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
    at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:115)
    at grails.plugin.springsecurity.web.UpdateRequestContextHolderExceptionTranslationFilter.doFilter(UpdateRequestContextHolderExceptionTranslationFilter.groovy:64)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at grails.plugin.springsecurity.web.filter.GrailsAnonymousAuthenticationFilter.doFilter(GrailsAnonymousAuthenticationFilter.groovy:53)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:150)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:169)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:200)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at grails.plugin.springsecurity.web.authentication.logout.MutableLogoutFilter.doFilter(MutableLogoutFilter.groovy:62)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at grails.plugin.springsecurity.web.SecurityRequestHolderFilter.doFilter(SecurityRequestHolderFilter.groovy:58)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177)
    at org.grails.web.servlet.mvc.GrailsWebRequestFilter.doFilterInternal(GrailsWebRequestFilter.java:77)
    at org.grails.web.filters.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:67)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: grails.views.ViewRenderException: Error rendering view: null
    at grails.views.AbstractWritableScript.writeTo(AbstractWritableScript.groovy:33)
    at grails.views.mvc.GenericGroovyTemplateView.renderMergedOutputModel(GenericGroovyTemplateView.groovy:71)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:303)
    at grails.views.mvc.renderer.DefaultViewRenderer.render(DefaultViewRenderer.groovy:105)
    at grails.artefact.controller.RestResponder$Trait$Helper.internalRespond(RestResponder.groovy:188)
    at grails.artefact.controller.RestResponder$Trait$Helper.respond(RestResponder.groovy:76)
    at com.wizpanda.ApplicationController.index(ApplicationController.groovy:52)
    ... 37 common frames omitted
Caused by: java.lang.StackOverflowError: null
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:744)
    at java.util.LinkedHashMap$LinkedEntryIterator.next(LinkedHashMap.java:742)
    at java.util.AbstractMap.hashCode(AbstractMap.java:507)
    at java.util.Objects.hashCode(Objects.java:98)
    at java.util.HashMap$Node.hashCode(HashMap.java:296)
    at java.util.AbstractMap.hashCode(AbstractMap.java:507)
    at java.util.Objects.hashCode(Objects.java:98)`

Here is the simple controller I'm using:

class ApplicationController {

    static allowedFormats = ["json"]

    def index() {
        Map result = [username: "foo"]
        respond(result)
    }
}

On hitting /application/index endpoint (expecting a JSON) request was working properly on 3.1.11 but started failing after upgrade to 3.2.0

After some debugging and reading change logs, we realized that a file views/object/_object.gson is added in Grails 3.2.0. On deleting that file, it started working fine.

Answer 1

This is a bug the workaround is indeed to remove grails-app/views/object/_object.gson.

Resolved by https://github.com/grails/grails-views/commit/27d2e546f9d723026fc4d0fb4c1384fa503d282c