Implement the fetchurl builtin, and lay the groundwork for implementing
the fetchTarball builtin (which works very similarly, and is implemented
using almost the same code in C++ nix).
An overview of how this works:
1. First, we check if the store path that *would* result from the
download already exists in the store - if it does, we just return
that
2. If we need to download the URL, TvixStoreIO has an `http_client:
reqwest::Client` field now which we use to make the request
3. As we're downloading the blob, we hash the data incrementally into a
SHA256 hasher
4. We compare the hash against the expected hash (if any) and bail out
if it doesn't match
5. Finally, we put the blob in the store and return the store path
Since the logic is very similar, this commit also implements a *chunk*
of `fetchTarball` (though the actual implementation will likely include
a refactor to some of the code reuse here).
The main thing that's missing here is caching of downloaded blobs when
fetchurl is called without a hash - I've opened b/381 to track the TODO
there.
Adding the `SSL_CERT_FILE` here is necessary to teach reqwest how to
load it during tests - see 1c16dee20 (feat(tvix/store): use reqwests'
rustls-native-roots feature, 2024-03-03) for more info.
Change-Id: I83c4abbc7c0c3bfe92461917e23d6d3430fbf137
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11017
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
Autosubmit: aspen <root@gws.fyi>
There's various bits and pieces in tvix-cli that use both the store and
evaluator, as well as nix-compat. For example, builtins.derivation, as
well as the reference scanning implementation.
This "glue code" currently isn't accessible from anywhere else, but it'd
be very useful if it were.
Move it out into a `glue` crate, and make `tvix-cli` a consumer of it.
All the KnownPaths setup and passing around, as well as NIX_PATH
handling is also something that should probably be moved into the glue
crate as well, but that's something left for a future CL.
Change-Id: I080ed3d1825ab23790666486840f301f00856277
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9908
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
