feat(tvix/glue/derivationStrict): support __structuredAttrs r/7376

This adds support to handle the __structuredAttrs argument, which can be
passed to builtins.derivationStrict.

If __structuredAttrs is passed, and set to true, most of the arguments
passed to builtins.derivationStrict are not simply coerced to a string
and passed down to "environments", but instead kept in a more structured
fashion.

Inside ATerm, which is what's relevant as far as path calculation is
concerned, a virtual `__json` environment variable is present,
containing these structured values.

Inside Builds, these structured values are not made available as an
environment variable, but a JSON file (and source-able bash script).

This will need to be respected once we start emitting BuildRequests,
and for that we can probably just parse the `__json` key in
Derivation.environment again - or keep this additionally in
non-serialized form around during Evaluation.
No matter what, this is left for a followup CL.

The existing handle_derivation_parameters and populate_outputs helper
function were removed, as __structuredAttrs causes quite a change
in behaviour, and so handling both in the same place makes it more
readable.

There's some open questions w.r.t. string contexts for structured attrs
itself. A TODO is left for this, but at least path calculation for
individual structured attrs derivations are correct now.

Part of b/366.

Change-Id: Ic293822266ced6f8c4826d8ef0d2e098a4adccaa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10604
Tested-by: BuildkiteCI
Reviewed-by: raitobezarius <tvl@lahfa.xyz>

1 files changed, 4 insertions, 1 deletions

diff --git a/tvix/glue/Cargo.toml b/tvix/glue/Cargo.toml
index ad776a48f7..c58c66dd60 100644
--- a/tvix/glue/Cargo.toml
+++ b/tvix/glue/Cargo.toml
@@ -4,16 +4,19 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+bstr = "1.6.0"
+bytes = "1.4.0"
 data-encoding = "2.3.3"
 nix-compat = { path = "../nix-compat" }
 tvix-build = { path = "../build", default-features = false, features = []}
 tvix-eval = { path = "../eval" }
 tvix-castore = { path = "../castore" }
 tvix-store = { path = "../store", default-features = false, features = []}
-bytes = "1.4.0"
 tracing = "0.1.37"
 tokio = "1.28.0"
 thiserror = "1.0.38"
+serde = "1.0.195"
+serde_json = "1.0"
 sha2 = "0.10.8"
 
 [dependencies.wu-manber]