Extend offline mode to disallow downloads to third party sites

[stoecker]

Currently offline mode allows to prevent OSM wiki and JOSM server access

It should allow as well at least these

• third party ressources
• remote links from inside the software (taginfo, wikipedia, ...)
• map images
• cache-refreshs

[simon04]

Replying to stoecker:

• cache-refreshs

Relates to #18162

[simon04]

In 16426/josm:

see #18712 - Add NetworkManager.isOffline(String) to test offline status of given URL

Deprecates OnlineResource.checkOfflineAccess(String, String)

[simon04]

In 16427/josm:

see #18712 - Add OfflineAccessException.forResource(String)

[simon04]

In 16428/josm:

see #18712 - CachedFile: report offline mode

[simon04]

In 16429/josm:

see #18712 - MainApplication: report localized resource names for offline mode

[simon04]

In 16430/josm:

fix #18162, see #18712 - Add --offline=CACHE_UPDATES to disable updates of CachedFiles

This includes imagery index, custom styles, presets.

[simon04]

Replying to stoecker:

• third party ressources
• remote links from inside the software (taginfo, wikipedia, ...)
• map images

For those resources I have troubles imagining a good use-case (speaking of JOSM core). We do not fetch third party resources, call the Taginfo API, fetch from Wikipedia at all (only open browser windows). The display of map images always requires a receding user action (maybe unless opening a OSM session file).

Perhaps are you imagining more like a permission granting system? – "Do you authorize JOSM fetching stuff from www.example.com?" or "Do you authorize JOSM connecting to www.example.com?"