https://www.sftravel.com/what-you-need-know-about-legal-marijuana-california
It is illegal to consume, smoke, eat or vape cannabis in public. It is illegal to open a package containing cannabis or any cannabis products in public. This includes but is not limited to parks and sidewalks, business and residential areas.
It is also illegal to consume cannabis in other locations where smoking is illegal, including bars, restaurants, buildings open to the public, places of employment and areas within 15 feet of doors and ventilation openings.