Cities database creation script

prepopulate-cities.ts

/**
 * Takes cities source files and populates SQLite database
 * @param schemaPath Where the Room schemas are put
 * @param dataDir Where the data is put
 * @return A promise for created database
 */
export async function cities(schemaPath: string, dataDir: string): Promise<string> {
    const schemaFile = await findLatestSchema(schemaPath);
    const timeStarted = Date.now();

    const name: string = Guid.create().toString();
    const path = Path.join(os.tmpdir(), `${name}.db`);
    const db = new Database(path);

    await populate(
        Path.join(schemaPath, schemaFile),
        db,
        async function(this: Database): Promise<void> {
            await citiesDb.populate(
                db,
                await readJsonData<Array<City>>(Path.join(dataDir, FILE_CITIES))
            );
        }
    );

    db.close();

    console.log("Total time: ", duration(Date.now() - timeStarted).humanize());
    return path;
}