Feature request: offline mode

[elichad]

We want to run the validator inside a Trusted Research Environment (TRE) - a compute environment which has no internet access.For this purpose, it would be useful to have a mode where:

• data that would be downloaded is instead retrieved from a cache if possible (see Feature request: cache downloaded contexts/vocabularies between runs #114). If the user could set the cache location, we would then be able to pre-load necessary data into the TRE for the validator to use
• checks that require an internet connection are skipped

[elichad]

@kikkomep can you indicate if you (or someone on your team) has capacity to work on this issue and/or #114 ? If not then we will have a look from our side, but you have more insider knowledge of what parts of the codebase fetch web resources.

[kikkomep]

Hi @elichad. Let me know if the PR #123 is helpful for this issue

[elichad]

@kikkomep thanks for working on this so quickly! It looks like #123 will fix #114, but won't allow the validator to run completely offline, so doesn't fully fix this issue.

When I create the cache, then disconnect from the network and run the validator using the cache, it still hangs on a few checks - I haven't checked which ones exactly.

[elichad]

Also, while thinking about how to implement full offline mode, I did a quick investigation on how one could block network access for certain unit tests and found the pytest-socket plugin - you can decorate desired tests with @pytest.mark.disable_socket to prevent network access.