feat: import_verifiable_stream and write_verifiable_stream in Store

[matheus23]

Description

• Adds a default-implemented fn Store::import_verifiable_stream
• Adds a default-implemented fn MapEntry::write_verifiable_stream

These allow interacting with the iroh_blobs store using iroh's bao-style streams.

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I'm coming across this while extracting iroh-willow into its own thing. This means merging in all work that's not yet merged into iroh yet from the willow PR/branch in iroh. This is one of these things.

IIUC, this allows us to stream the willow entry payloads directly from the WGPS protocol instead of having to simultaneously run iroh-blobs & iroh-willow.

Breaking Changes

Adding fn to traits should be non-breaking as long as they have default impls, right?

Notes & Open Questions

Unfortunately no tests with this yet, other than my pinky-promise that this code has worked so far for iroh-willow.
That said, I haven't tried bigger payloads yet.

I'll probably make use of this branch for the iroh-willow extraction and come back eventually to add proper tests.

Change checklist

• Self-review.
• Documentation updates following the style guide, if relevant.
• Tests if relevant.
• All breaking changes documented.

[matheus23]

I still requested a review just to confirm: Is this a feature we want to support in iroh-blobs?
If so, I'll come back and add some tests to this.
If not, I won't waste time on writing tests & we'll need to think of some other way of doing this & revise the use in iroh-willow.

[github-actions]

Documentation for this PR has been generated and is available at: https://n0-computer.github.io/iroh-blobs/pr/10/docs/iroh_blobs/

Last updated: 2024-12-12T15:51:27Z

[rklaehn]

I find it a bit weird that this is defined on MapEntry.

Wouldn't it be better to have this as a store fn that uses MapEntry? MapEntry really does everything it needs to do.

Also, it would be cool if we could make this more generic, otherwise we will have a dozen methods for special cases, like in this case streaming from offset..end of the file.

[rklaehn]

Where does the total_size come from? Is it a verified size?