passing json in json to spring controller - ajax

Question

I am trying to pass json object to spring controller and I manage to do that, but value of one property is in json and I think that I have problem because of it. But there is no other way to pass that data. Code is below,
data class:
#Entity
data class Section(
#Id
#GeneratedValue
val id: Long = 0L,
val name: String = "",
var text: String,
#ManyToOne
var notebook: Notebook
)
Controller code:
#PutMapping("/sections/{id}")
fun updateSection(#RequestBody section: Section, #PathVariable id: Long): Section =
sectionRepository.findById(id).map {
it.text = section.text
it.notebook = section.notebook
sectionRepository.save(it)
}.orElseThrow { SectionNotFoundException(id) }
javascript sending post to api:
function updateApi(data) {
axios.put(MAIN_URL + 'sections/' + data.id, {
data
})
.then(showChangesSaved())
.catch(ShowErrorSync());
}
function saveSection() {
var data = JSON.parse(window.sessionStorage.getItem("curr-section"));
data.text = JSON.stringify(element.editor).toString();
updateApi(data);
}
I get error like this:
2020-11-18 15:06:24.052 WARN 16172 --- [nio-8080-exec-2] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Instantiation of [simple type, class org.dn.model.Section] value failed for JSON property text due to missing (therefore NULL) value for creator parameter text which is a non-nullable type; nested exception is com.fasterxml.jackson.module.kotlin.MissingKotlinParameterException: Instantiation of [simple type, class org.dn.model.Section] value failed for JSON property text due to missing (therefore NULL) value for creator parameter text which is a non-nullable type
at [Source: (PushbackInputStream); line: 1, column: 375] (through reference chain: org.dn.model.Section["text"])]
so text in element.editor is JSON formatted string and I need to pass it as it is to controller. Is there any way to do that? I tried searching, but I can't find json in json help...
Whole project is available on github

Answer 1

What does your json looks like? If I check out your project and run the following two tests:
one with Section as an object as request body
one with Section as json
Both will succeed. So the problem might lie in your JSON:
#SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
class HttpRequestTest {
#LocalServerPort
private val port = 0
#Autowired
private val restTemplate: TestRestTemplate? = null
#Test
fun sectionAsObject() {
val section = Section(0L, "2L", "text", Notebook(1L, "1", "2"))
assertThat(restTemplate!!.put("http://localhost:$port/sections/123", section
)).isNotNull
}
#Test
fun sectionAsJson() {
val sectionAsJson = """
{
"id": 0,
"name": "aName",
"text": "aText",
"noteBook": {
"id": 0,
"name": "aName",
"desc": "2"
}
}
""".trimIndent()
assertThat(restTemplate!!.put("http://localhost:$port/sections/123", sectionAsJson
)).isNotNull
}
}
BTW: it is not a pretty good habit to expose your database ids, which is considered to be a security risk as it exposes your database layer. Instead, you might want to use a functional unique key ;)