improper utf-8 handling in json-unit-spring

[octopus-prime]

Describe the bug

• JsonUnit 2.11.0
• BringBoot 2.2.0.RELEASE

When using json-unit with rest-assured all works fine:

        given(specification)
                .with()
                .accept(MediaType.APPLICATION_JSON_VALUE)
                .queryParam("produktIds", PreisApiData.PRODUKT_IDS)

                .when()
                .get("preise")

                .then()
                .statusCode(HttpStatus.OK.value())

                .assertThat()
                .contentType(MediaType.APPLICATION_JSON_VALUE)
                .body(jsonEquals(PreisApiData.PREIS_DTOS));

But writing the same test with json-unit-spring and mock-mvc causes encoding issues:

        mockMvc.perform(get("/preise")
                .accept(MediaType.APPLICATION_JSON)
                .param("produktIds", PreisApiData.PRODUKT1_ID.toString(), PreisApiData.PRODUKT2_ID.toString()))
                .andExpect(status().isOk())
                .andExpect(content().contentTypeCompatibleWith(MediaType.APPLICATION_JSON))
                .andExpect(json().isEqualTo(PreisApiData.PREIS_DTOS));

->

Different value found in node "[0].currency", expected: <"€"> but was: <"â�¬">.
Comparison Failure: 
Expected :€
Actual   :�

[octopus-prime]

Maybe in JsonUnitResultMatchers the code could be changed from

        @Override
        public void match(MvcResult result) throws Exception {
            String actual = result.getResponse().getContentAsString();
            doMatch(actual);
        }

to

        @Override
        public void match(MvcResult result) throws Exception {
            String actual = result.getResponse().getContentAsString(StandardCharsets.UTF_8);
            doMatch(actual);
        }

[lukas-krecan]

Good catch, thanks, will fix it.

[lukas-krecan]

It seems that it's a problem on your side. Spring takes the encoding form the response content type. Can you check the 'Content-Type' header returned by the controller? I was able to reproduce it like this (you should do the opposit :)) https://github.com/lukas-krecan/JsonUnit/compare/unicode?expand=1

[octopus-prime]

Note that
MediaType.APPLICATION_JSON_UTF8
and
MediaType.APPLICATION_JSON_UTF8_VALUE
are deprecated since Spring 5.2 (and so in Spring Boot 2.2) with reason

	/**
	 * Public constant media type for {@code application/json;charset=UTF-8}.
	 * @deprecated Deprecated as of Spring Framework 5.2 in favor of {@link #APPLICATION_JSON}
	 * since major browsers like Chrome
	 * <a href="https://bugs.chromium.org/p/chromium/issues/detail?id=438464">
	 * now comply with the specification</a> and interpret correctly UTF-8 special
	 * characters without requiring a {@code charset=UTF-8} parameter.
	 */

So the controller implements this API

@Tag(name = "Preis")
public interface PreisApi {

    @Operation(summary = "Get kunde")
    @GetMapping(path = "preise", produces = MediaType.APPLICATION_JSON_VALUE)
    @ResponseStatus(HttpStatus.OK)
    Set<PreisDto> getPreise(@RequestParam("produktIds") Set<UUID> produktIds);
}

My proposed fix would try to
'interpret correctly UTF-8 special characters without requiring a {@code charset=UTF-8} parameter.'

[lukas-krecan]

Ok, it's quite a mess but this should help #213

[lukas-krecan]

Released as 2.11.1