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ext.integrity

Pure functions for computing and verifying file checksums over Store's public API. These compose store.read() with ChecksumReader internally — no manual stream lifecycle management needed.

See the integrity spec for invariants.

integrity

Checksum verification helpers over Store's public API.

Pure functions for computing and verifying file integrity. These compose store.read() with ChecksumReader internally — users don't need to manage stream lifecycle.

Example

from remote_store.ext.integrity import checksum, verify

algorithm, hex_digest = checksum(store, "data/file.bin")
print(algorithm, hex_digest)

ok = verify(store, "data/file.bin", expected="a3f2b8...", algorithm="sha256")

checksum 

checksum(
    store: Store, path: str, algorithm: str = "sha256"
) -> tuple[str, str]

Compute the checksum of a file in the store.

Reads the file in chunks (never fully materialized in memory) and returns a (algorithm, hex_digest) tuple.

Parameters:

  • store (Store) –

    The Store to read from.

  • path (str) –

    Store-relative file path.

  • algorithm (str, default: 'sha256' ) –

    Hash algorithm name (default "sha256").

Returns:

  • tuple[str, str] –

    Tuple of (algorithm, hex_digest) with lowercase values.

Raises:

  • NotFound –

    If the file does not exist.

  • ValueError –

    If the algorithm is not supported by hashlib.

content_digest 

content_digest(
    store: Store, path: str, algorithm: str = "sha256"
) -> ContentDigest

Compute the content digest of a file in the store.

Like checksum, but returns a ContentDigest instead of a raw tuple.

Parameters:

  • store (Store) –

    The Store to read from.

  • path (str) –

    Store-relative file path.

  • algorithm (str, default: 'sha256' ) –

    Hash algorithm name (default "sha256").

Returns:

Raises:

  • NotFound –

    If the file does not exist.

  • ValueError –

    If the algorithm is not supported by hashlib.

verify 

verify(
    store: Store,
    path: str,
    expected: str,
    algorithm: str = "sha256",
) -> bool

Verify a file's checksum against an expected hex value.

Parameters:

  • store (Store) –

    The Store to read from.

  • path (str) –

    Store-relative file path.

  • expected (str) –

    Expected hex digest (case-insensitive).

  • algorithm (str, default: 'sha256' ) –

    Hash algorithm name (default "sha256").

Returns:

  • bool –

    True if the computed digest matches expected.

Raises:

  • NotFound –

    If the file does not exist.

  • ValueError –

    If the algorithm is not supported by hashlib.

verify_hex 

verify_hex(
    store: Store,
    path: str,
    algorithm: str,
    expected_hex: str,
) -> bool

Verify a file's checksum given an algorithm and expected hex value.

Parameters:

  • store (Store) –

    The Store to read from.

  • path (str) –

    Store-relative file path.

  • algorithm (str) –

    Hash algorithm name.

  • expected_hex (str) –

    Expected hex digest (case-insensitive).

Returns:

  • bool –

    True if the computed digest matches expected_hex.

Raises:

  • NotFound –

    If the file does not exist.

  • ValueError –

    If the algorithm is not supported by hashlib.

See also

  • ext.streams — composable BinaryIO wrappers used internally by integrity helpers