Outdoor bayonet light fixture stopped working
Since you have no measured voltage , I would be looking for a fuse or circuit breaker that has tripped. That bulb style in not used in my area for mains lighting. In my area I would work back to the switch then to find what feeds the switch sometimes a receptacle looking for another dead device that could have caused the open circuit or no voltage continuing to work back to the main power panel verifying that any branch fuses are good.