What I have:
I'm generating a JSON schema from a pojo. My code to generate the schema looks like so:
ObjectMapper mapper = new ObjectMapper();
TitleSchemaFactoryWrapper visitor = new TitleSchemaFactoryWrapper();
mapper.acceptJsonFormatVisitor(clazz, visitor);
JsonSchema schema = visitor.finalSchema();
schemas.put(clazz, mapper.writerWithDefaultPrettyPrinter().writeValueAsString(schema));
I'm generating several schemas via the above code. One of the pojos has an internal embedded enum to limit the possible values, like so:
public class MyClass {
@JsonProperty("name")
private String name;
@JsonProperty("startDayOfWeek")
private MyClass.StartDayOfWeek startDayOfWeek;
/**
* The ID of a timezone returned by the timezones route.
*
*/
@JsonProperty("timezone")
private String timezone;
@JsonIgnore
private Map<String, Object> additionalProperties = new HashMap<String, Object>();
/**
*
* @return
* The startDayOfWeek
*/
@JsonProperty("startDayOfWeek")
public MyClass.StartDayOfWeek getStartDayOfWeek() {
return startDayOfWeek;
}
/**
*
* @param startDayOfWeek
* The startDayOfWeek
*/
@JsonProperty("startDayOfWeek")
public void setStartDayOfWeek(MyClass.StartDayOfWeek startDayOfWeek) {
this.startDayOfWeek = startDayOfWeek;
}
public static enum StartDayOfWeek {
MONDAY("Monday"),
TUESDAY("Tuesday"),
WEDNESDAY("Wednesday"),
THURSDAY("Thursday"),
FRIDAY("Friday"),
SATURDAY("Saturday"),
SUNDAY("Sunday");
private final String value;
private static Map<String, MyClass.StartDayOfWeek> constants = new HashMap<String, MyClass.StartDayOfWeek>();
static {
for (MyClass.StartDayOfWeek c: values()) {
constants.put(c.value, c);
}
}
private StartDayOfWeek(String value) {
this.value = value;
}
@JsonValue
@Override
public String toString() {
return this.value;
}
@JsonCreator
public static MyClass.StartDayOfWeek fromValue(String value) {
MyClass.StartDayOfWeek constant = constants.get(value);
if (constant == null) {
throw new IllegalArgumentException(value);
} else {
return constant;
}
}
}
}
The above code should limit the possible String values in the JSON data that's passed around to "Monday", "Tuesday", "Wednesday", etc.
When I run the schema generator on the code in question, I expect to get something like the following schema:
{
"type" : "object",
"javaType" : "my.package.MyClass",
"properties": {
"startDayOfWeek" : {
"type" : "string",
"enum" : [ "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" ]
}
}
}
but instead I'm getting this:
{
"type" : "object",
"id" : "urn:jsonschema:my:package:MyClass",
"title" : "Lmy/package/MyClass;",
"properties" : {
"startDayOfWeek" : {
"type" : "string"
}
}
}
I've done some digging in the Jackson Schema Module source code and figured out that what's happening is Jackson's using ".toString()" as the default serialization method for enum types, but what I need it to do instead is create the line that looks like this based on StartDayOfWeek.values()
:
"enum" : [ "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday" ]
Does anyone know how to do that?
Storme's answer references org.codehaus
, which is an older version of jackson. The following is similar but uses fasterxml (newer version).
Pom:
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.7.1</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.7.1</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.7.1</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.module</groupId>
<artifactId>jackson-module-jsonSchema</artifactId>
<version>2.1.0</version>
</dependency>
Code:
import ...TargetClass;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.jsonschema.JsonSchema;
import java.io.IOException;
public final class JsonSchemaGenerator {
private JsonSchemaGenerator() { };
public static void main(String[] args) throws IOException {
System.out.println(JsonSchemaGenerator.getJsonSchema(TargetClass.class));
}
public static String getJsonSchema(Class clazz) throws IOException {
ObjectMapper mapper = new ObjectMapper();
mapper.configure(SerializationFeature.WRITE_ENUMS_USING_TO_STRING, true);
JsonSchema schema = mapper.generateJsonSchema(clazz);
return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(schema);
}
}