A git inspired blockchain filesystem

[frank-dspeed]

git is one of the best blockchain implementations that we got today

but its content hash is also based on the filename as you can see in refs/objects/<sha256-1 cont

const entrieHash = `${filename.length}\0${fs.readFileSync(filename)}`

file_name="your_file";
printf "blob $(wc -c < "$file_name")\0$(cat "$file_name")" | sha1sum

In Rust:

// Get the object ID
fn git_hash_object(file_content: &[u8]) -> Vec<u8> {

    let file_size = file_content.len().to_string();
    let hash_input: Vec<u8> = vec![
        "blob ".as_bytes(),
        file_size.as_bytes(),
        b"\0",
        file_content,
    ]
    // Flatten the Vec<&[u8]> to Vec<u8> with concat
    .concat();
    to_sha1(&hash_input)
}

fn to_sha1(hash_me: &[u8]) -> Vec<u8> {
    // using [crate sha1](https://docs.rs/sha1/0.6.0/sha1/) version 0.6.0 in to_sha1:
    let mut m = Sha1::new();
    m.update(hash_me);
    m.digest().bytes().to_vec()
}

git entry hash

bash version look if you got utf8 already

locale charmap

if it returns UTF-8

printf %s "filename" |  openssl dgst -sha256 –binary 

IFS read username from stdin as a sequence of bytes assumed to be encoded from characters as per the locale's encoding
if it is not utf-8 use iconv the utf 8 lib convert from locale encoding to UTF-8

IFS= read -r $filename
printf %s "$filename" |
  iconv -t utf-8 | 
  openssl dgst -sha256 –binary 

//printf "blob $(wc -c < "$file_name")\0$(cat "$file_name")" | sha1sum
 //[mode] [file name]\0[object ID]

tree object

The format of a tree object:

tree [content size]\0[Entries having references to other trees and blobs]
The format of each entry having references to other trees and blobs:

[mode] [file/folder name]\0[SHA-1 of referencing blob or tree]
I wrote a script deflating tree objects. It outputs as follows:

tree 192\0
40000 octopus-admin\0 a84943494657751ce187be401d6bf59ef7a2583c
40000 octopus-deployment\0 14f589a30cf4bd0ce2d7103aa7186abe0167427f
40000 octopus-product\0 ec559319a263bc7b476e5f01dd2578f255d734fd
100644 pom.xml\0 97e5b6b292d248869780d7b0c65834bfb645e32a
40000 src\0 6e63db37acba41266493ba8fb68c76f83f1bc9dd