City, Lviv
Lviv(UA) City Open Data
Nantes(FR) City Open Data.
City, Nantes Open Data API is a free Government API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Données publiques ouvertes (Open data) mises à disposition par la Ville de Nantes et Nantes Métropole.
Details from data.nantesmetropole.fr.

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Lviv(UA) City Open Data
The City, Nantes Open Data API is provided by Accueil — Open Data Nantes Métropole (data.nantesmetropole.fr). Données publiques ouvertes (Open data) mises à disposition par la Ville de Nantes et Nantes Métropole.
Yes. The City, Nantes Open Data API is listed in the Government category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The City, Nantes Open Data API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the City, Nantes Open Data API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The City, Nantes Open Data API is served over HTTPS, so it's safe to use in production.