Tiles cache

[fitoprincipe]

Hi, I'd like to know if tiles are downloaded into a cache folder. If not, is there any possibility to implement this? Thank you.

[martinRenou]

Hi, tiles are not downloaded to a cache folder. There are some plugins for LeafletJS that allows caching of tiles, like this one: https://github.com/MazeMap/Leaflet.TileLayer.PouchDBCached. Adding this feature to ipyleaflet should be easy using this plugin, but I start to be a little bit annoyed by the number of dependencies, and most of them are not maintained.

I suppose there is some caching already with the browser, but it does not last long.

[fitoprincipe]

I understand @martinRenou, thank you for your time.

[martinRenou]

Do you think that having the tiles in a folder and using something like a LocalTilesLayer in ipyleaflet, as discussed here would be enough for your use case? I guess you want caching for being able to use ipyleaflet without an internet connection, is that it?

[fitoprincipe]

I made a tool upon ipyleaflet to visualize tiles pulled from GEE (Google Earth Engine) (my tool: https://github.com/gee-community/gee_tools/blob/master/notebooks/ui/map_visualization.ipynb). I use it a lot myself, and that is why I am able to maintain it. If you sing up to GEE you can try it out.

Basically, using Google Earth Engine Python API I do some raster manipulation on their servers and they serve me the result as tiles (url), so every time I request a tile, their servers compute it and serve it (which may take long). Downloading the raster images would take much longer and would miss the point of "playing around" with GEE.

[martinRenou]

Ok I see :) I guess we can try adding the plugin for caching. It should not be too difficult.

[fitoprincipe]

That would be great! Thank you =)

[martinRenou]

I looked closer to Leaflet.PouchDBCached, it's not maintained anymore, apparently does not support the last version of LeafletJS and PouchDB. https://github.com/MazeMap/Leaflet.TileLayer.PouchDBCached/issues/38 On the other hand, it's not a lot of code, I guess it would not be that difficult to implement something similar.

[fitoprincipe]

Thanks for keeping this alive @martinRenou. May be if you guide me, I could help you, but that could be an extra effort for you, and whatever is your decision is fine to me. =)

[martinRenou]

Sure I can guide you :) I think the way to go would be to take a look at this file from Leaflet.TileLayer.PouchDBCached, and try to implement your own version that supports the last version of LeafletJS. I don't know if a dependency like PouchDB is essential. But to avoid duplication of effort I think it would be a good idea to answer to this issue first, I guess his code coulld be what we need :)