Introduce a two-tier cache for blob payloads backed by the foyer crate
(memory + disk). The cache is configured via CacheConfig and exposed
through src/cache/{mod,global}.rs.
Why foyer:
- HybridCache gives us bounded RAM plus disk overflow without bringing
in our own eviction / spill logic.
- The runtime-tokio feature plays cleanly with the existing tokio stack.
Touches:
- src/cache/mod.rs: CacheConfig, CacheStore, CacheKey/Value aliases,
default-into-disk fallback (CacheConfig::default)
- src/cache/global.rs: process-wide singleton accessor for the default
cache
- src/error.rs: new BabyError::Cache { op, source } variant wrapping
foyer::Error so cache failures share the existing error pipeline
- Cargo.toml: add foyer = "0.22.3" with runtime-tokio feature
- src/lib.rs: pub mod cache; (wiring only — no public API on GitBaby
changes yet)
- src/tree/types.rs: drive-by import reorder (serde before std::path)
to match rustfmt
CI: cargo build + cargo test (38 passed) green.
Skipped intentionally: no git/lfs protocol logic is added here; this
commit is purely the storage substrate.
Add the serde 'twins' (Serialize + Deserialize) to every public struct
and enum in src/*/types.rs so data types can be serialized via JSON,
bincode, postcard, etc.
Dependency changes:
- enable 'serde' feature on gix (for gix::ObjectId)
- enable 'serde' feature on time (for time::OffsetDateTime)
Skipped:
- src/archive/types.rs::ChildArchiveReader<R> — contains a
tokio::process::Child field, semantically not serializable
Coverage (18 modules):
archive, blame, blob, branch, cleanup, commit, compare, config,
conflict, diff, merge, refs, remote, setup, submodule, tags, tree
Notes:
- field names kept snake_case (no rename_all remap)
- existing PartialEq / Eq / Default / Copy derives preserved
- cargo build + cargo test (38 passed) green
