How to use the flower.api.tasks.BaseTaskHandler function in flower

broker_use_ssl = self.capp.conf.BROKER_USE_SSL

        broker = Broker(app.capp.connection().as_uri(include_password=True),
                        http_api=http_api, broker_options=broker_options, broker_use_ssl=broker_use_ssl)

        queue_names = ControlHandler.get_active_queue_names()

        if not queue_names:
            queue_names = set([self.capp.conf.CELERY_DEFAULT_QUEUE]) |\
                        set([q.name for q in self.capp.conf.CELERY_QUEUES or [] if q.name])

        queues = yield broker.queues(sorted(queue_names))
        self.write({'active_queues': queues})


class ListTasks(BaseTaskHandler):
    @web.authenticated
    def get(self):
        """
List tasks

**Example request**:

.. sourcecode:: http

  GET /api/tasks HTTP/1.1
  Host: localhost:5555
  User-Agent: HTTPie/0.8.0

**Example response**:

.. sourcecode:: http

:statuscode 200: no error
:statuscode 401: unauthorized request
:statuscode 404: unknown task
        """
        args, kwargs, options = self.get_task_args()
        logger.debug("Invoking task '%s' with '%s' and '%s'",
                     taskname, args, kwargs)
        result = self.capp.send_task(
            taskname, args=args, kwargs=kwargs, **options)
        response = {'task-id': result.task_id}
        if self.backend_configured(result):
            response.update(state=result.state)
        self.write(response)


class TaskResult(BaseTaskHandler):
    @web.authenticated
    def get(self, taskid):
        """
Get a task result

**Example request**:

.. sourcecode:: http

  GET /api/task/result/c60be250-fe52-48df-befb-ac66174076e6 HTTP/1.1
  Host: localhost:5555

**Example response**:

.. sourcecode:: http

expires = float(expires)
            except ValueError:
                expires = datetime.strptime(expires, self.DATE_FORMAT)
            options['expires'] = expires

    def safe_result(self, result):
        "returns json encodable result"
        try:
            json.dumps(result)
        except TypeError:
            return repr(result)
        else:
            return result


class TaskApply(BaseTaskHandler):
    @web.authenticated
    @gen.coroutine
    def post(self, taskname):
        """
Execute a task by name and wait results

**Example request**:

.. sourcecode:: http

  POST /api/task/apply/tasks.add HTTP/1.1
  Accept: application/json
  Accept-Encoding: gzip, deflate, compress
  Content-Length: 16
  Content-Type: application/json; charset=utf-8
  Host: localhost:5555

:statuscode 200: no error
:statuscode 401: unauthorized request
:statuscode 503: result backend is not configured
        """
        logger.info("Aborting task '%s'", taskid)

        result = AbortableAsyncResult(taskid)
        if not self.backend_configured(result):
            raise HTTPError(503)

        result.abort()

        self.write(dict(message="Aborted '%s'" % taskid))


class GetQueueLengths(BaseTaskHandler):
    @web.authenticated
    @gen.coroutine
    def get(self):
        """
Return length of all active queues

**Example request**:

.. sourcecode:: http

  GET /api/queues/length
  Host: localhost:5555

**Example response**:

.. sourcecode:: http

"tasks.sleep"
      ]
  }

:reqheader Authorization: optional OAuth token to authenticate
:statuscode 200: no error
:statuscode 401: unauthorized request
        """
        seen_task_types = self.application.events.state.task_types()

        response = {}
        response['task-types'] = seen_task_types
        self.write(response)


class TaskInfo(BaseTaskHandler):
    @web.authenticated
    def get(self, taskid):
        """
Get a task info

**Example request**:

.. sourcecode:: http

  GET /api/task/info/91396550-c228-4111-9da4-9d88cfd5ddc6 HTTP/1.1
  Accept: */*
  Accept-Encoding: gzip, deflate, compress
  Host: localhost:5555


**Example response**:

response = yield IOLoop.current().run_in_executor(
            None, self.wait_results, result, response)
        self.write(response)

    def wait_results(self, result, response):
        # Wait until task finished and do not raise anything
        result.get(propagate=False)
        # Write results and finish async function
        self.update_response_result(response, result)
        if self.backend_configured(result):
            response.update(state=result.state)
        return response


class TaskAsyncApply(BaseTaskHandler):
    DATE_FORMAT = '%Y-%m-%d %H:%M:%S.%f'

    @web.authenticated
    def post(self, taskname):
        """
Execute a task

**Example request**:

.. sourcecode:: http

  POST /api/task/async-apply/tasks.add HTTP/1.1
  Accept: application/json
  Accept-Encoding: gzip, deflate, compress
  Content-Length: 16
  Content-Type: application/json; charset=utf-8

except KeyError:
            raise HTTPError(404, "Unknown task '%s'" % taskname)

        try:
            self.normalize_options(options)
        except ValueError:
            raise HTTPError(400, 'Invalid option')

        result = task.apply_async(args=args, kwargs=kwargs, **options)
        response = {'task-id': result.task_id}
        if self.backend_configured(result):
            response.update(state=result.state)
        self.write(response)


class TaskSend(BaseTaskHandler):
    @web.authenticated
    def post(self, taskname):
        """
Execute a task by name (doesn't require task sources)

**Example request**:

.. sourcecode:: http

  POST /api/task/send-task/tasks.add HTTP/1.1
  Accept: application/json
  Accept-Encoding: gzip, deflate, compress
  Content-Length: 16
  Content-Type: application/json; charset=utf-8
  Host: localhost:5555

timeout = float(timeout) if timeout is not None else None

        result = AsyncResult(taskid)
        if not self.backend_configured(result):
            raise HTTPError(503)
        response = {'task-id': taskid, 'state': result.state}

        if timeout:
            result.get(timeout=timeout, propagate=False)
            self.update_response_result(response, result)
        elif result.ready():
            self.update_response_result(response, result)
        self.write(response)


class TaskAbort(BaseTaskHandler):
    @web.authenticated
    def post(self, taskid):
        """
Abort a running task

**Example request**:

.. sourcecode:: http

  POST /api/task/abort/c60be250-fe52-48df-befb-ac66174076e6 HTTP/1.1
  Host: localhost:5555

**Example response**:

.. sourcecode:: http

type = type if type != 'All' else None
        state = state if state != 'All' else None

        result = []
        for task_id, task in tasks.iter_tasks(
                app.events, limit=limit, type=type,
                worker=worker, state=state,
                received_start=received_start,
                received_end=received_end):
            task = tasks.as_dict(task)
            task.pop('worker', None)
            result.append((task_id, task))
        self.write(dict(result))


class ListTaskTypes(BaseTaskHandler):
    @web.authenticated
    def get(self):
        """
List (seen) task types

**Example request**:

.. sourcecode:: http

  GET /api/task/types HTTP/1.1
  Host: localhost:5555

**Example response**:

.. sourcecode:: http