Help with ClassCastException when running unit tests

[devon66h]

Hi there, I recently implemented a custom context with the DGS Fetching Context. In doing so I am getting the following error when running unit tests:

java.lang.ClassCastException: class com.netflix.graphql.dgs.internal.DgsWebMvcRequestData cannot be cast to class com.x.server.graphql.context.GraphQLContext

Here is my unit test for reference:

@SpringBootTest(classes = [PlaidResolver::class])
@EnableDgsTest
class PlaidResolverTest : DescribeSpec() {
    @Autowired
    lateinit var dgsQueryExecutor: DgsQueryExecutor

    @MockkBean
    lateinit var plaidService: PlaidService

    override fun extensions() = listOf(SpringExtension)

    init {
        describe("createPlaidLinkToken") {
            it("successfully creates link token") {
                val linkTokenMock = "linkToken"

                every {
                    plaidService.createLinkToken(any())
                } returns CreateLinkTokenResponse(linkToken = linkTokenMock)

                val response = dgsQueryExecutor.executeAndExtractJsonPathAsObject(
                    """
                    mutation {
                        createPlaidLinkToken { 
                            linkToken 
                        } 
                    }
                    """.trimIndent(),
                    "data.createPlaidLinkToken",
                    CreatePlaidLinkTokenResponse::class.java
                )

                response.linkToken shouldBe linkTokenMock
                verify(exactly = 1) { plaidService.createLinkToken(any()) }
            }
        }
   }

And here is my resolver and context builder implementation:

@DgsComponent
class PlaidResolver(private val plaidService: PlaidService) {
    @DgsMutation
    fun createPlaidLinkToken(dfe: DgsDataFetchingEnvironment): CreatePlaidLinkTokenResponse {
        val context = DgsContext.getCustomContext<GraphQLContext>(dfe)
        val userId = context.userId ?: throw UnauthenticatedException()
        val response = plaidService.createLinkToken(userId)
        return CreatePlaidLinkTokenResponse(linkToken = response.linkToken)
    }
}

data class GraphQLContext(
    val userId: String?
)

@Component
class GraphQLContextBuilder(private val supabaseClient: SupabaseClient) :
    DgsCustomContextBuilderWithRequest<GraphQLContext> {
    override fun build(extensions: Map<String, Any>?, headers: HttpHeaders?, webRequest: WebRequest?): GraphQLContext {
        return GraphQLContext(userId = "fake-for-now")
    }
}

build.gradle.kts:

dependencies {
    implementation("org.springframework.boot:spring-boot-starter-web")
    implementation("com.fasterxml.jackson.module:jackson-module-kotlin")
    implementation("com.netflix.graphql.dgs:graphql-dgs-spring-graphql-starter")
    implementation("org.flywaydb:flyway-core")
    implementation("org.jetbrains.kotlin:kotlin-reflect")
    implementation("com.plaid:plaid-java:25.0.0")
    implementation(platform("io.github.jan-tennert.supabase:bom:2.6.1"))
    implementation("io.github.jan-tennert.supabase:gotrue-kt")
    implementation("io.ktor:ktor-client-java:2.3.12")
    testImplementation("org.springframework.boot:spring-boot-starter-test")
    testImplementation("io.kotest:kotest-runner-junit5:5.9.1")
    testImplementation("io.kotest:kotest-assertions-core:5.9.1")
    testImplementation("io.kotest:kotest-property:5.9.1")
    testImplementation("io.kotest.extensions:kotest-extensions-spring:1.3.0")
    testImplementation("io.mockk:mockk:1.13.12")
    testImplementation("com.ninja-squad:springmockk:4.0.2")
    testImplementation("com.netflix.graphql.dgs:graphql-dgs-spring-graphql-starter-test")
}

dependencyManagement {
    imports {
        mavenBom("com.netflix.graphql.dgs:graphql-dgs-platform-dependencies:latest.release")
    }
}

Any idea here would be greatly appreciated!

[devon66h]

After removing the (classes = [PlaidResolver::class]) reference in the @SpringBootTest annotation this worked. Presumably because I wasn't referencing all the necessary classes involved.