Add ability to filter layers from geocoder result sets in LocationFieldComponent about otp-ui

[fpurcell]

Hey Paul ... in the short term, it might be best to remove the routes from the geocoder. There isn't a good way to exclude a layer in Pelias atm. It's on the Pelias roadmap, but not quite yet available: pelias/pelias#844

[fpurcell]

That said, we could / should add to otp-ui a prop to define the 'layers' param being sent down to geocoder (Pelias) requests. In terms of trimet.org, you'd set layers=-routes whenever you don't want any routes to show up in the results. But until Pelias is ready to accept the exclusive layers values, we'd have to filter sources as a param on the geocoder service, else we'd have problems, ala: https://ws-st.trimet.org/pelias/v1/autocomplete?text=20%20burnside%20stark&sources=-routes

[PaulIvanov]

Hey thanks for the information Frank. For a short term fix, until pelias has the feature available, would we be able to still pass in the layers we want so that the geocoder can filter after the pelias service comes back with results?