Constant MissingServletRequestParameterException

For some reason, I continously get the error message:

MissingServletRequestParameterException: Required String[] parameter 'ids' is not present

I have an endpoint which can be called from /products?ids=["item1", "item2"]

My integration test class looks like so:

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.runners.MockitoJUnitRunner;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@RunWith(MockitoJUnitRunner.class)
public class ProductControllerTest {

    private MockMvc mockMvc;

    @InjectMocks
    private ProductController controller;

    @Before
    public void setup() {
        mockMvc = MockMvcBuilders.standaloneSetup(controller).build();
    }

    @Test
    public void shouldFetchProducts() throws Exception {
        mockMvc.perform(get("/products")
                .param("ids[]", "[\"item\"]"))
                .andExpect(status().is2xxSuccessful());
    }
}

What I've tried:

1. Using param

   @Test
   public void shouldFetchProducts() throws Exception {
       mockMvc.perform(get("/products")
               .param("ids[]", "[\"item\"]"))
               .andExpect(status().is2xxSuccessful());
   }
   
   

2. Using requestAttr

   @Test public void shouldFetchProducts() throws Exception { mockMvc.perform(get("/products/non-options") .requestAttr("ids[]", "[\"ukx\"]")) .andExpect(status().is2xxSuccessful()); }

What am I doing wrong?