# JSON Compatible Encoder { #json-compatible-encoder }

There are some cases where you might need to convert a data type (like a Pydantic model) to something compatible with JSON (like a `dict`, `list`, etc).

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder` { #using-the-jsonable-encoder }

    /**
     * Convert a model profile to a settings profile.
     */
    @Nonnull
    org.apache.maven.api.settings.Profile convert(@Nonnull org.apache.maven.api.model.Profile profile);

    /**
     * Convert a settings profile to a model profile.
     */
    @Nonnull
    org.apache.maven.api.model.Profile convert(@Nonnull org.apache.maven.api.settings.Profile profile);

## Convert any Data to JSON-compatible { #convert-any-data-to-json-compatible }

To convert any data to JSON-compatible, read the docs for [Tutorial - JSON Compatible Encoder](../tutorial/encoder.md){.internal-link target=_blank}.

For example, you cannot put a Pydantic model in a `JSONResponse` without first converting it to a `dict` with all the data types (like `datetime`, `UUID`, etc) converted to JSON-compatible types.

For those cases, you can use the `jsonable_encoder` to convert your data before passing it to a response:

{* ../../docs_src/response_directly/tutorial001_py310.py hl[5:6,20:21] *}

/// note | Technical Details

    }

    /**
     * Parses a sequence of XML elements and converts them to the appropriate array type.
     *
     * @param parser The XML parser
     * @return Converted array instance
     */
    private Object parseArray(final MXParser parser, final TypeLiteral<?> toType) throws Exception {
        // convert to a collection first then convert that into an array

But if the data didn't exist, you want to create it, and return an HTTP status code of "CREATED" `201`.

But you still want to be able to filter and convert the data you return with a `response_model`.

For those cases, you can use a `Response` parameter.

## Use a `Response` parameter { #use-a-response-parameter }

				a.setInt(iA)
			} else if fA, ok := a.bytesToFloat(); ok {
				a.setFloat(fA)
			} else {
				return fmt.Errorf("Could not convert %s to a number", a.String())
			}

		case bool:
			if bA, ok := a.bytesToBool(); ok {
				a.setBool(bA)
			} else {
				return fmt.Errorf("Could not convert %s to a boolean", a.String())
			}

		default:
			return errCmpMismatchedTypes
		}
		return nil

            "msg": "Extra inputs are not permitted",
            "input": "plumbus",
        }
    ]
}
```

## Disable Convert Underscores { #disable-convert-underscores }

The same way as with regular header parameters, when you have underscore characters in the parameter names, they are **automatically converted to hyphens**.

    }

    /**
     * Convert property using appropriate converter.
     */
    private Object convertProperty(
            Class<?> beanType, Class<?> rawPropertyType, Type genericPropertyType, PlexusConfiguration configuration)
            throws ComponentConfigurationException {

        ConfigurationConverter converter = lookup.lookupConverterForType(rawPropertyType);

	policyCondStartsWith    = "starts-with"
	policyCondContentLength = "content-length-range"
)

// toString - Safely convert interface to string without causing panic.
func toString(val any) string {
	switch v := val.(type) {
	case string:
		return v
	default:
		return ""
	}
}

// toLowerString - safely convert interface to lower string
func toLowerString(val any) string {