dmreiland / snapdiff

CLI tool for comparing the difference between two directory snapshots

snapdiff

snapdiff can compare two snapshots of a directory tree, which have been captured at different points in time. (Think of a “snapshot” as a backup of the original directory tree, in the sense of a full copy.) It diffs the two snapshots, and summarizes how many files are identical, and how many have been moved, modified, added, or deleted. That way, you get a high-level insight into how the data evolved between both snapshots.

Learn more in this blog post.

Example

Say, you want to compare two snapshots, one taken at 2023-09-01, and another one taken at 2023-10-01:

$ snapdiff 2023-09-01/ 2023-10-01/

                           FILES             BYTES
                                     G   M   K   B
TOTAL       Snap 1        87,243    98,407,188,994
            Snap 2        87,319    98,591,738,372
            
OF WHICH    Identical     87,134    97,551,550,976
            Moved             38       134,217,728
            Added             87       234,881,024
            Deleted           11        50,331,648
            Modified         147       671,088,644 (+282,172)

The categories are defined as:

• Identical: both snapshots contain a file at the same path with the same contents.
• Moved: both snapshots contain a file with the same contents, but at different paths.
• Added: the second snapshot contains a file whose path or contents is not present in the first snapshot.
• Deleted: the first snapshot contains a file whose path or contents is not present in the second snapshot.
• Modified: both snapshots contain a file at the same path, but with different contents.

Usage

snapdiff
    [--report PATH]
    [--include-dot-paths]
    [--include-symlinks]
    [--workers N] OR [--workers N1:N2]
    [--no-color]
    SNAP1 SNAP2

SNAP1 and SNAP2 are in “chronological” order, so snapshot 1 is assumed to precede snapshot 2.

See also snapdiff --help for info.

--report PATH

Example: --report ./my-report.txt

Print a detailed report to a file.

The file will be newly created, so it fails if a file already exists at the target path.

--include-dot-paths

Include files and folders whose name start with a dot (.), instead of ignoring them (which is the default).

--include-symlinks

Resolve symlinks, instead of ignoring them (which is the default).

--workers N

Example: --workers 4 or --workers 1:8

The number of workers (CPU cores) to utilize.

0 means that it detects the number of available CPU cores automatically (which is the default).

You can specify two different values, separated by a colon (:), to differentiate between the first and the second snapshot.

--no-color

Print output in plain text, without colouring.

Build from Sources

Prerequisites: Rust toolchain (see Cargo.toml for required version).

Compile via cargo build. (Produces binary to target/debug/snapdiff.)

About

snapdiff was created by Jan Heuermann. The sources are available under the terms of the MIT license.