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JsonFormat not supported?

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
java
Domain
backend-api-design

Research direction

Reproduce the schema generation with the Wound entity, ObjectMapper, JavaTimeModule, and JsonSchemaGenerator shown in the issue. Compare the generated LocalDateTime array or object with the expected string schema, then trace how JsonFormat annotations and JavaTimeModule types are handled. Done means the documented pattern produces the expected date-time schema without Java member properties.

Written by the indexing model from the issue text.

Description

Entity:

public class Wound {

    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ss", timezone = "UTC")
    @JsonProperty("createdAt")
    @JsonPropertyDescription("A date time object w/o timezone.")
    @NotNull
    private LocalDateTime createdAt;

}

When I generate with JavaTimeModule(), I get an array of integer in the json schema:

        ObjectMapper objectMapper = new ObjectMapper();
                .registerModule(new JavaTimeModule());

        JsonSchemaGenerator jsonSchemaGenerator = new JsonSchemaGenerator(objectMapper);
        JsonNode jsonSchema = jsonSchemaGenerator.generateJsonSchema(Wound.class);
        String jsonSchemaAsString = objectMapper.writeValueAsString(jsonSchema);

        "createdAt": {
          "type": "array",
          "items": {
            "type": "integer"
          },
          "description": "A date time object w/o timezone."
        }

When I omit the JavaTimeModule, I a get a LocalDateTimeObject with Java members:

    "LocalDateTime": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "dayOfYear": {
          "type": "integer"
        },
        "dayOfWeek": {
          "type": "string",
          "enum": [
            "MONDAY",
            "TUESDAY",
            "WEDNESDAY",
            "THURSDAY",
            "FRIDAY",
            "SATURDAY",
            "SUNDAY"
          ]
        },
        "year": {
          "type": "integer"
        },
...

EXPECTED RESULT:

    "dateTime": {
      "description": "A date time object w/o timezone.",
      "type": "string",
      "format": "date-time",
      "javaType": "java.time.LocalDateTime",
      "customDateTimePattern" : "yyyy-MM-dd'T'HH:mm:ss"
    }
Dominant language
Java
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