Copying tiles from HTTP → MBTiles hangs

[mojodna]

This made it as far as 19/307226/288527 and then hung:

nvm use 5
npm install tl tilelive-http mbtiles
node_modules/.bin/tl copy http://a.tile.openstreetmap.org/{z}/{x}/{y}.png mbtiles://./osm_dvizarasekwa_z14-20.mbtiles -b "30.904111862182614 -17.821343531895728 30.95578193664551 -17.778602961844793" -z 14 -Z 20

[mojodna]

'Twas primarily operator error (OSM tiles are only available to z19 and slowly 404 afterward). Since 404s are treated as absent data, it was attempting to retrieve all of them (but not retrying).

I did add a bunch of new debugging capabilities in the process of figuring this out though, which should be handy for the future.