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StreamStore

snapdir_stores::stream

Trait StreamStore 

Source 
pub trait StreamStore: Store {
    // Required methods
    fn has_object(&self, checksum: &str) -> Result<bool, StoreError>;
    fn get_object(&self, checksum: &str) -> Result<Vec<u8>, StoreError>;
    fn put_object(
        &self,
        checksum: &str,
        bytes: Vec<u8>,
    ) -> Result<(), StoreError>;
    fn put_manifest(
        &self,
        id: &str,
        manifest: &Manifest,
    ) -> Result<(), StoreError>;

    // Provided method
    fn objects_needed(
        &self,
        checksums: &[String],
    ) -> Result<Vec<String>, StoreError> { ... }
}
Expand description

Raw, content-addressed object/manifest streaming on top of a Store.

See the module docs for the store-to-store sync motivation and the verification invariants. The Store supertrait means every implementor also offers get_manifest, fetch_files, and push.

Required Methods§

Source

fn has_object(&self, checksum: &str) -> Result<bool, StoreError>

Returns true if an object with this content-address already exists in the store.

This is the existence check a store-to-store orchestrator uses to skip re-copying blobs the destination already holds. It does not read or verify the object body.

§Errors

StoreError::Io / StoreError::Backend on transport failure.

Source

fn get_object(&self, checksum: &str) -> Result<Vec<u8>, StoreError>

Reads the raw object blob filed under checksum, verifying its bytes hash (BLAKE3) back to checksum before returning them.

§Errors
Source

fn put_object(&self, checksum: &str, bytes: Vec<u8>) -> Result<(), StoreError>

Writes a raw object blob at its content-address, verifying bytes hash (BLAKE3) to checksum before storing anything.

A mismatch stores nothing and returns an error, so a corrupt blob can never land at a content-address it does not belong to.

§Errors
Source

fn put_manifest(&self, id: &str, manifest: &Manifest) -> Result<(), StoreError>

Writes the manifest object for id, verifying the manifest’s bytes hash back to id before storing it.

This is the final step of a store-to-store copy: it is written only after every referenced object has landed, so a manifest is never observable before the content it references (mirroring push).

§Errors

Provided Methods§

Source

fn objects_needed( &self, checksums: &[String], ) -> Result<Vec<String>, StoreError>

Returns the subset of checksums NOT present in the store, PRESERVING INPUT ORDER.

This is the diff primitive behind the snapdir objects-needed wire plumbing (SNAPPACK acceleration, see crate::pack): a sender offers a snapshot’s full object list and the receiver answers with exactly the objects it still needs, so only those ride the pack stream.

Semantics:

  • Fail closed: every checksum is validated against ^[0-9a-f]{64}$ (crate::pack::is_hex64) BEFORE the first existence probe; any invalid entry is a hard error and nothing is returned (a malformed request must never be partially answered).
  • Order-preserving, no dedup: the returned complement keeps the input order, and deduplication is the CALLER’s job — an absent checksum supplied twice is reported twice.
  • The default implementation loops has_object (one existence probe per checksum). Follow-up (not this gate): the S3/GCS backends should override this with their batched listing APIs to cut round trips — any override must preserve the exact contract above.
§Errors
  • StoreError::Backend if any checksum is not 64 lowercase hex characters (fail closed, before any probe).
  • Whatever has_object surfaces on transport failure.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§