[andrew_eu]

I have a memorable reverse geocoding story.

I was working with a team that was wrapping up a period of many different projects (including a reverse geocoding service) and adopting one major system to design and maintain. The handover was set to be after the new year holidays and the receiving teams had their own exciting rewrites planned. I was on call the last week of the year and got an alert that sales were halted in Taiwan due to some country code issue and our system seemed at fault. The customer facing application used an address to determine all sorts of personalization stuff: what products they're shown, regulatory links, etc. Our system was essentially a wrapper around Google Maps' reverse geocoding API, building in some business logic on top of the results.

That morning, at 3am, the API stopped serving the country code for queries of Kinmen County. It would keep the rest of the address the same, but just omit the country code, totally botching assumptions downstream. Google Maps seemingly realized all of a sudden what strait the island was in, and silently removed what some people dispute.

Everyone else on the team was on holiday and I couldn't feasibly get a review for any major mitigations (e.g. switching to OSM or some other provider). So I drew a simple polygon around the island, wrote a small function to check if the given coordinates were in the polygon, and shipped the hotfix. Happily, the whole reverse geocoding system was scrapped with a replacement by February.

[modeless]

Wow, I had no idea that Taiwan controlled an island less than three miles from mainland China, essentially surrounded by China in a bay. (The main island is 80+ miles away.) I'm really surprised China has allowed that for 80 years. Unsurprisingly, the beach looks like this: https://www.google.com/maps/place/Shuang+Kou+Zhan+Dou+Cun/@2...

Also interesting that there's a Japanese island only 60 miles from Taiwan on the other side. I guess claims to small Pacific islands have been weird for a long time.

[nradov]

If the Chinese Communist Party decides to escalate the pressure on Taiwan then one likely scenario is some sort of blockade against those small islands close to the mainland.

[marc_abonce]

I faced the same issue with locations inside Crimea and Kashmir. The Google Places API wouldn't return a country code for those regions. At the time I couldn't find any documentation from Google specifying which inhabited locations return a null country code, I assume they want to avoid any potential controversy. Unfortunately this lack of documentation makes it harder to work around this issue.