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Hi @shuheiktgw. Thanks for your PR.

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This behavior could lead to a hard-to-find bug when a user mistakenly tries to paginate with the limit and continue option by the cache client. I faced the problem, and that was quite hard to debug since the limit option works correctly and I always received the first page only.

I believe that I faced the same issue here.

I have one concern: a typical flow of using pagination is you set Limit to your page size and leave Continue empty in your first List call. This fix wouldn't catch that someone is trying to use CacheReader with pagination as Continue would be empty anyway.

As CacheReader.List accepts ListOptions with both Limit and Continue, claiming de facto it implements the client.Reader interface, wouldn't it make sense to simulate the continuation on its side? If we don't do that, it's always on the caller's side to know what kind of a client is being used and account for continuations not working for some of them, which is not a perfect situation. I'd expect the interface to be implemented consistently despite the implementation details.

As CacheReader.List accepts ListOptions with both Limit and Continue, claiming de facto it implements the client.Reader interface, wouldn't it make sense to simulate the continuation on its side?

Thats on the callers side anyways, because the two are not identical, they just expose an identical interface. You for example have to know that if you get data from cache it might be stale and deal with that properly.

Thats on the callers side anyways, because the two are not identical, they just expose an identical interface. You for example have to know that if you get data from cache it might be stale and deal with that properly.

If that's expected to not implement some options it technically accepts, could we make sure that these intentional gaps are properly documented?

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alvaroaleman, shuheiktgw

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This still leads to hard to find bugs if the client tries to use continue (rather than just calling List() once with a limit, ignoring the continue flag). As long as the cache doesn't support continue, List() calls should probably just return an arbitrary non-empy continue string so that if the client copies that into into the next request, they'll fail-fast into this error. rather than just getting a single, seemingly truncated list with no error.