JsonPatch test operation is testing against updated json node [DATAREST-769]

Mathias D opened DATAREST-769 and commented

The JsonPatchHandler is using the patchedNode for TestOperation. So it is checking against the result of the update. The test operation is a precondition - so it should be checked against the existingNode.

At the moment I cannot use the TestOperation to assert the old value of an attribute.

I wrote a simple test to reproduce the behaviour in org.springframework.data.rest.webmvc.jpa.JpaWebTests

@Test
	public void createThenPatchWithTest() throws Exception {

		Link peopleLink = client.discoverUnique("people");

		MockHttpServletResponse bilbo = postAndGet(peopleLink, "{ \"firstName\" : \"Bilbo\", \"lastName\" : \"Baggins\" }",
				MediaType.APPLICATION_JSON);

		Link bilboLink = client.assertHasLinkWithRel("self", bilbo);

		assertThat((String) JsonPath.read(bilbo.getContentAsString(), "$.firstName"), is("Bilbo"));
		assertThat((String) JsonPath.read(bilbo.getContentAsString(), "$.lastName"), is("Baggins"));
		String json = mapper.writeValueAsString(ImmutableList.of(
				ImmutableMap.builder()
						.put("op", "replace")
						.put("path", "/firstName")
						.put("value", "patched name").build(),
				ImmutableMap.builder()
						.put("op", "test")
						.put("path", "/firstName")
						.put("value", "Bilbo").build()
		));
		MockHttpServletResponse frodo = patchAndGet(bilboLink, json, RestMediaTypes.JSON_PATCH_JSON);

		assertThat((String) JsonPath.read(frodo.getContentAsString(), "$.firstName"), is("patched name"));
	}

At the moment the order of operations matters - it works if the replace operation is before the test operation.

I think the JsonPatchHandler should handle the test operations before the other operations

Affects: 2.4.2 (Gosling SR2)

2 votes, 3 watchers