How to use the connexion.utils.all_json function in connexion

If the operation mimetype format is json then the function return value is jsonified

        From Swagger Specification:

        **Produces**

        A list of MIME types the operation can produce. This overrides the produces definition at the Swagger Object.
        An empty value MAY be used to clear the global definition.

        :rtype: types.FunctionType
        """

        logger.debug('... Produces: %s', self.produces, extra=vars(self))

        mimetype = self.get_mimetype()
        if all_json(self.produces):  # endpoint will return json
            logger.debug('... Produces json', extra=vars(self))
            # TODO: Refactor this.
            return lambda f: f

        elif len(self.produces) == 1:
            logger.debug('... Produces %s', mimetype, extra=vars(self))
            decorator = Produces(mimetype)
            return decorator

        else:
            return BaseSerializer()

def get_mimetype(self):
        """
        If the endpoint has no 'produces' then the default is
        'application/json'.

        :rtype str
        """
        if all_json(self.produces):
            try:
                return self.produces[0]
            except IndexError:
                return DEFAULT_MIMETYPE
        elif len(self.produces) == 1:
            return self.produces[0]
        else:
            return DEFAULT_MIMETYPE

def get_mimetype(self):
        """
        If the endpoint has no 'produces' then the default is
        'application/json'.

        :rtype str
        """
        if all_json(self.produces):
            try:
                return self.produces[0]
            except IndexError:
                return DEFAULT_MIMETYPE
        elif len(self.produces) == 1:
            return self.produces[0]
        else:
            return DEFAULT_MIMETYPE

def wrapper(request):
        logger.debug('Function Arguments: %s', arguments)
        kwargs = {}

        if all_json(consumes):
            request_body = request.json
        else:
            request_body = request.body

        if default_body and not request_body:
            request_body = default_body

        # Parse path parameters
        path_params = request.path_params
        for key, path_param_definitions in path_types.items():
            if key in path_params:
                kwargs[key] = get_val_from_param(path_params[key],
                                                 path_param_definitions)

        # Add body parameters
        if not has_kwargs and body_name not in arguments:

def is_json_schema_compatible(self, response_schema):
        """
        Verify if the specified operation responses are JSON schema
        compatible.

        All operations that specify a JSON schema and have content
        type "application/json" or "text/plain" can be validated using
        json_schema package.

        :type response_schema: dict
        :rtype bool
        """
        if not response_schema:
            return False
        return all_json([self.mimetype]) or self.mimetype == 'text/plain'

If the operation mimetype format is json then the function return value is jsonified

        From Swagger Specification:

        **Produces**

        A list of MIME types the operation can produce. This overrides the produces definition at the Swagger Object.
        An empty value MAY be used to clear the global definition.

        :rtype: types.FunctionType
        """

        logger.debug('... Produces: %s', self.produces, extra=vars(self))

        mimetype = self.get_mimetype()
        if all_json(self.produces):  # endpoint will return json
            logger.debug('... Produces json', extra=vars(self))
            # TODO: Refactor this.
            return lambda f: f

        elif len(self.produces) == 1:
            logger.debug('... Produces %s', mimetype, extra=vars(self))
            decorator = Produces(mimetype)
            return decorator

        else:
            return BaseSerializer()