User forked version of serde-bencode

[josecelano]

Using our crate torrust-serde-bencode instead of the upstream repo fixes the problem with some torrent deserializations described in this issue.

There was a problem with lists (field nodes in the torrent) containing other lists (tuples) with different value types.

{
   "info": {
      "length": 8,
      "name": "minimal.txt",
      "piece length": 16384,
      "pieces": "<hex>30 9A 84 51 4A F1 09 D0 8C 34 42 11 26 67 7F 84 B3 23 4D 78</hex>"
   },
   "nodes": [
      [
         "188.163.121.224",
         56711
      ],
      [
         "162.250.131.26",
         13386
      ]
   ]
}

I have been trying to reproduce the bug in our fork here, but it works. I've added a test using the same torrent file that does not work here.

If you run:

cargo run --bin parse_torrent ./tests/fixtures/torrents/not-working-with-two-nodes.torrent 

With the current develop branch, you'll see that it does NOT work. But It works using our fork.

For this PR, I have changed the cargo.toml file to include the latest commit from the fork. And it works.

Surprisingly, it also works with:

torrust-serde-bencode = "^0.2.3"

Which was supposed to be the same code as:

serde_bencode = "^0.2.3"

So, no idea why it's working with an almost-exact copy of the original package.

Anyway, serde_bencode is not maintained. So I'll will:

• Publish a new version for torrust-serde-bencode.
• Change this PR to use the new version torrust-serde-bencode = "^0.2.4".

[codecov-commenter]

Codecov Report

Merging #316 (3550c44) into develop (db99842) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop     #316      +/-   ##
===========================================
+ Coverage    42.45%   42.47%   +0.01%     
===========================================
  Files           79       79              
  Lines         4803     4801       -2     
===========================================
  Hits          2039     2039              
+ Misses        2764     2762       -2     

Files	Coverage Δ
src/models/torrent_file.rs	70.58% <100.00%> (+0.48%)	⬆️

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[josecelano]

Finally, I've found the problem. The deserialisation works with the original serde_bencode package too. The only change needed was replacing the Option<Vec<TorrentNode>> with Option<Vec<(String, i64)>>. It could be a bug with the deserialization described here.

But the struct can be changed to avoid using tuple structs.

#[derive(PartialEq, Debug, Clone, Serialize, Deserialize)]
pub struct Torrent {
    pub info: TorrentInfoDictionary, //
    #[serde(default)]
    pub announce: Option<String>,
    #[serde(default)]
    pub nodes: Option<Vec<TorrentNode>>, // <- change this to Option<Vec<(String, i64)>>,
    #[serde(default)]
    pub encoding: Option<String>,
    #[serde(default)]
    pub httpseeds: Option<Vec<String>>,
    #[serde(default)]
    #[serde(rename = "announce-list")]
    pub announce_list: Option<Vec<Vec<String>>>,
    #[serde(default)]
    #[serde(rename = "creation date")]
    pub creation_date: Option<i64>,
    #[serde(default)]
    pub comment: Option<String>,
    #[serde(default)]
    #[serde(rename = "created by")]
    pub created_by: Option<String>,
}

After changing that, you can rerun this command:

x$ cargo run --bin parse_torrent ./tests/fixtures/torrents/not-working-with-two-nodes.torrent 
   Compiling torrust-index-backend v2.0.0-alpha.3 (/home/josecelano/Documents/git/committer/me/github/torrust/torrust-index)
    Finished dev [unoptimized + debuginfo] target(s) in 6.01s
     Running `target/debug/parse_torrent ./tests/fixtures/torrents/not-working-with-two-nodes.torrent`
Reading the torrent file ...
Decoding torrent with standard serde implementation ...
Parsed torrent: 
Torrent {
    info: TorrentInfoDictionary {
        name: "minimal.txt",
        pieces: Some(
            [
                48,
                154,
                132,
                81,
                74,
                241,
                9,
                208,
                140,
                52,
                66,
                17,
                38,
                103,
                127,
                132,
                179,
                35,
                77,
                120,
            ],
        ),
        piece_length: 16384,
        md5sum: None,
        length: Some(
            8,
        ),
        files: None,
        private: None,
        path: None,
        root_hash: None,
        source: None,
    },
    announce: None,
    nodes: Some(
        [
            (
                "188.163.121.224",
                56711,
            ),
            (
                "162.250.131.26",
                13386,
            ),
        ],
    ),
    encoding: None,
    httpseeds: None,
    announce_list: None,
    creation_date: None,
    comment: None,
    created_by: None,
}

and you'll see the two nodes.

I'm going to keep the fork because:

• I've made some improvements and plan to do more.
• The package is not maintained anymore.

[josecelano]

It works with the original serde_bencode crate but not with the latest publish crate (v0.2.3).

@madadam was fixing that problem, but a new version was not published after the fixing.

See the latest commits https://github.com/toby/serde-bencode/commits/master

• Add test for ser/de of struct with vec of tuples
• Fix deserialization of nested tuple

That's why it's working with the fork (latest commit) because it includes those fixes. I will continue working on the fork and publish a new version. After that we can use that version on this PR.

[josecelano]

I've published a new version (0.2.4) of the serde_bencode. This PR should work with the newer version.

[josecelano]

It's fixed with serde_bencode 0.2.4

$ cargo run --bin parse_torrent ./tests/fixtures/torrents/not-working-with-two-nodes.torrent 
   Compiling torrust-index v3.0.0-alpha.3-develop (/home/josecelano/Documents/git/committer/me/github/torrust/torrust-index)
    Finished dev [unoptimized + debuginfo] target(s) in 2.61s
     Running `target/debug/parse_torrent ./tests/fixtures/torrents/not-working-with-two-nodes.torrent`
Reading the torrent file ...
Decoding torrent with standard serde implementation ...
Parsed torrent: 
Torrent {
    info: TorrentInfoDictionary {
        name: "minimal.txt",
        pieces: Some(
            [
                48,
                154,
                132,
                81,
                74,
                241,
                9,
                208,
                140,
                52,
                66,
                17,
                38,
                103,
                127,
                132,
                179,
                35,
                77,
                120,
            ],
        ),
        piece_length: 16384,
        md5sum: None,
        length: Some(
            8,
        ),
        files: None,
        private: None,
        path: None,
        root_hash: None,
        source: None,
    },
    announce: None,
    nodes: Some(
        [
            (
                "188.163.121.224",
                56711,
            ),
            (
                "162.250.131.26",
                13386,
            ),
        ],
    ),
    encoding: None,
    httpseeds: None,
    announce_list: None,
    creation_date: None,
    comment: None,
    created_by: None,
}

[josecelano]

ACK 3550c44