Proposal: Move OpenAPI Generated Java Sources to Gradle-Compliant Directory

[qa-alexander-schreiner]

Proposal: Move OpenAPI Generated Java Sources to Gradle-Compliant Directory

Context

Currently, the Quarkus OpenAPI Generator outputs generated Java source files to:

build/classes/java/quarkus-generated-sources/open-api

build/classes/ is conventionally reserved for compiled .class files. Placing .java source files here can lead to significant issues during test execution and build tooling interactions.

Problem

Misplacing generated .java sources in a compiled-output directory causes:

• Annotation processors like Lombok to not run (e.g., .builder() methods not generated)
• Test builds to recompile the source into test output, breaking runtime expectations
• NoSuchMethodError at runtime due to missing constructors or builder-methods

Proposal

Change the output path for generated Java source files to:

build/generated/sources/openapi/java

[hbelmiro]

Sounds reasonable to me.
@ricardozanini @mcruzdev thoughts?

[qa-alexander-schreiner]

FYI:

this is the gradle task i added to workaround this issue:

tasks.register('relocateAllOpenApiSources') {
    dependsOn 'quarkusGenerateCode','quarkusGenerateCodeTests', 'quarkusGenerateCodeDev', 'generateEffectiveLombokConfig'

    doLast {
        // Move main-generated sources
        copy {
            from 'build/classes/java/quarkus-generated-sources/open-api'
            into 'build/generated/sources/openapi/java'
            include '**/*.java'
        }

        // Move test-generated sources
        copy {
            from 'build/classes/java/quarkus-test-generated-sources/open-api'
            into 'build/generated/sources/openapiTest/java'
            include '**/*.java'
        }

        delete fileTree('build/classes/java/quarkus-test-generated-sources/open-api') {
            include '**/*.java'
        }

        delete fileTree('build/classes/java/quarkus-generated-sources/open-api') {
            include '**/*.java'
        }
    }
}


// Ensure compileJava depends on the relocation
compileJava {
    dependsOn tasks.relocateAllOpenApiSources
}

[ricardozanini]

@qa-alexander-schreiner this path is handled by Quarkus under the hood, IIRC. I'd rather not change it so we won't break compatibility with our parent framework. Can also potentially break devmode: https://stackoverflow.com/questions/66199052/setting-target-directory-for-grpc-classes-generated-by-quarkus-gradle-plugin

The grpc extension is our cousin, so that reply also applies to us.

[ricardozanini]

One more thing: I think this is a relevant discussion, though. You can open a thread on Quarkus Zulip message board about the code generation extensions and Quarkus. I bet they already solved this problem. @gastaldi do you know who can we contact about this?

@qa-alexander-schreiner by the way, I'm assuming you're using Quarkus Gradle? https://quarkus.io/guides/gradle-tooling

[qa-alexander-schreiner]

@ricardozanini yes using quarkus gradle plugin if that's what you mean:

plugins {
    id 'java'
    id 'io.quarkus' version "3.15.4"
    // [...]
}

[qa-alexander-schreiner]

The problem is just that i have lombok annotations on the generated java code.
The lombok annotation processor usually creates the constructor and builder logic accordingly.
This also works fine for everything within build/classes/java/main. But within build/classes/java/test (used during test runtime) the constructor and builder logic is not being generated. Since my tests rely on them to exist, my tests are failing.

The workaround that i've commented here earlier is also not very stable, unfortunately.
Do you have an idea, what I can do about this?

Also thank you already for your asistence, really appreciate your effort :)

[ricardozanini]

How is your project structured? Why are you using lombok on the Rest Client generated Java code? If the objects are defined in the openapi spec, the extension should have generated the models and getters/setters for you. You don't need an additional generator.

[qa-alexander-schreiner]

all my objects that i use within the responses of my endpoint's methods are defined within src/main/resources/openapi/components.yaml. They're also referenced within my openapi.yaml file specifying all these endpoints.
Via my pojo.cute file i generate the java files accordingly.

it looks like this:

{@org.openapitools.codegen.CodegenModel m}
import com.fasterxml.jackson.annotation.JsonProperty;

{#if m.description}
/**
 * {m.description}
 **/
{/if}
@lombok.Builder
@lombok.With
@lombok.extern.jackson.Jacksonized
@lombok.Data
@lombok.NoArgsConstructor
@lombok.AllArgsConstructor
{#include additionalModelTypeAnnotations.qute m=m/}
{#if m.discriminator && m.discriminator.mappedModels && !m.discriminator.mappedModels.empty}
@com.fasterxml.jackson.annotation.JsonIgnoreProperties(
  value = "{m.discriminator.propertyBaseName}", // ignore manually set {m.discriminator.propertyBaseName}, it will be automatically generated by Jackson during serialization
  allowSetters = true // allows the {m.discriminator.propertyBaseName} to be set during deserialization
)
@com.fasterxml.jackson.annotation.JsonTypeInfo(use = com.fasterxml.jackson.annotation.JsonTypeInfo.Id.NAME, include = com.fasterxml.jackson.annotation.JsonTypeInfo.As.PROPERTY, property = "{m.discriminator.propertyBaseName}", visible = true)
@com.fasterxml.jackson.annotation.JsonSubTypes({
{#for child in m.discriminator.mappedModels}
    @com.fasterxml.jackson.annotation.JsonSubTypes.Type(value = {child.modelName}.class, name = "{#if m.vendorExtensions.x-discriminator-value.or('') == ''}{child.mappingName}{#else}{m.vendorExtensions.x-discriminator-value}{/if}"),
{/for}
})
{#else}
@com.fasterxml.jackson.annotation.JsonIgnoreProperties(ignoreUnknown = true)
{/if}
public class {m.classname} {#if m.parent}extends {m.parent}{/if}{#if serializableModel} implements java.io.Serializable{/if} {

{! ######## Variables ######### !}
    {#for v in m.vars}
    {#if m.vendorExtensions.x-is-query-parameter.or(false)}
    @jakarta.ws.rs.QueryParam("{v.baseName}")
    {/if}

    {#if !v.deprecated || openapi:genDeprecatedModelAttr(package, m.classname, codegen)}
    {#if v.isEnum}
    {#if v.isContainer && v.mostInnerItems}
    {#include enumClass.qute e=v/}
    {#else if !v.isContainer}
    {#include enumClass.qute e=v/}{/if}
    {/if}
    {#if v.hasValidation || v.required}{#include beanValidation.qute p=v/}{/if}
    {#if v.isContainer}
    private {v.datatypeWithEnum} {v.name}{#if v.required && v.defaultValue} = {v.defaultValue}{/if};
    {#else}
    private {v.datatypeWithEnum} {v.name}{#if v.defaultValue} = {v.defaultValue}{/if};
    {/if}
    {/if}
    {/for}

    {#for v in m.vars}
    {#if !v.deprecated || openapi:genDeprecatedModelAttr(package, m.classname, codegen)}
    /**
    {#if v.description}
     * {v.description}
    {#else}
     * Get {v.name}
    {/if}
    {#if v.minimum}
     * minimum: {v.minimum}
    {/if}
    {#if v.maximum}
     * maximum: {v.maximum}
    {/if}
     * @return {v.name}
    **/
    @JsonProperty("{v.baseName}")
    {#if !v.required}
    @com.fasterxml.jackson.annotation.JsonInclude(com.fasterxml.jackson.annotation.JsonInclude.Include.NON_NULL)
    {/if}
    {/if}
    {#if v.hasValidation || v.required}
    {#include beanValidation.qute p=v}
    {/if}
    {#if v.defaultValue && !v.isContainer}
    {#if !m.vendorExtensions.x-is-body-parameter}
    {#if v.isString}
    @jakarta.ws.rs.DefaultValue({v.defaultValue})
    {#else}
    @jakarta.ws.rs.DefaultValue("{v.defaultValue}")
    {/if}
    {/if}
    @lombok.Builder.Default
    {/if}
    {#if v.isEnum && v.isContainer}public {v.datatypeWithEnum} {v.getter}(){
        return {v.name};
    }{#else if v.isEnum && !v.isArray && !v.isMap}public {v.datatypeWithEnum} {v.getter}() {
        return {v.name};
    }{#else if !v.isEnum && !v.isArray && !v.isMap}public {v.datatype} {v.getter}() {
        return {v.name};
    }{#else if !v.isEnum && (v.isArray || v.isMap)}public {v.datatype} {v.getter}() {
        return {v.name};
    }{#else if !v.isEnum}public {v.datatype} {v.getter}() {
        return {v.name};
    }{/if}
    {/for}
}

I do not generate any rest client.
But the builder's and constructors are important since they're used within my unit tests

[ricardozanini]

Why are you creating custom templates to add lombok if we do generate getters and setters?

[qa-alexander-schreiner]

I was not aware, that getters and setters are already generated.

however i need (allargs-)contructors and builders for my tests to work.

Alternatively I also can re-structure my tests to only rely on getters/setters as a workaround, but this is not my favored solution, tbh.

[ricardozanini]

Can you have the generated files in a separate module and have the tests in another one?

[lloydmeta]

This was mentioned in the description but I think an example of this breaking build tooling expectations is disableWarningsInGeneratedCode.set(true) for ErrorProne: it expects generated things to be in that dir.