DIRECT search city with Python without server deployment: RuntimeError: Cannot run the event loop while another loop is running

[myrainbowandsky]

Ubuntu 22.04
python 3.9.13

current folder: project/website
nominatim is in ../../

import sys
sys.path.append('../../')

from pathlib import Path

import nominatim.api as napi

api = napi.NominatimAPI(Path('.'))

results = api.search('Brugge')

if not results:
    print('Cannot find Brugge')
else:
    print(f'Found a place at {results[0].centroid.x},{results[0].centroid.y}')

I got:

---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
Cell In[3], line 10
      6 import nominatim.api as napi
      8 api = napi.NominatimAPI(Path('.'))
---> 10 results = api.search('Brugge')
     12 if not results:
     13     print('Cannot find Brugge')

File /mnt/data/Nominatim/project_wenlu/website/../../nominatim/api/core.py:731, in NominatimAPI.search(self, query, **params)
    635 def search(self, query: str, **params: Any) -> SearchResults:
    636     """ Find a place by free-text search. Also known as forward geocoding.
    637 
    638         Parameters:
   (...)
    729                in the formats requested in the `geometry_output` parameter.
    730     """
--> 731     return self._loop.run_until_complete(
    732                self._async_api.search(query, **params))

File ~/anaconda3/lib/python3.9/asyncio/base_events.py:623, in BaseEventLoop.run_until_complete(self, future)
    612 """Run until the Future is done.
    613 
    614 If the argument is a coroutine, it is wrapped in a Task.
   (...)
    620 Return the Future's result, or raise its exception.
    621 """
    622 self._check_closed()
--> 623 self._check_running()
    625 new_task = not futures.isfuture(future)
    626 future = tasks.ensure_future(future, loop=self)

File ~/anaconda3/lib/python3.9/asyncio/base_events.py:585, in BaseEventLoop._check_running(self)
    583     raise RuntimeError('This event loop is already running')
    584 if events._get_running_loop() is not None:
--> 585     raise RuntimeError(
    586         'Cannot run the event loop while another loop is running')

RuntimeError: Cannot run the event loop while another loop is running

[lonvia]

This code example works fine for me. Do you run this snippet separately or as part of a larger script?

Also, Ubuntu 22.04 ships with Python 3.10 by default. Do you use some special setup?

[rpahut]

Though it's an old question
NominatimAPI cannot be used in a Notebook as it tries to run an event loop which is already started by the Jupyter. NominatimAPIAsync needs to be used instead, and the search coroutine specifically placed on a separate thread

async def _search_address(addr_text):
    async with napi.NominatimAPIAsync(Path('.')) as api:
        try:
            return await api.search(addr_text)
        except TimeoutError:
            print(f'TimeoutError while searching {addr_text}')

search_coro = _search_address('Brugge')
future = asyncio.run_coroutine_threadsafe(search_coro, _eventloop_running_on_separate_thread)
return future.result()