Essentials to implement a custom managed Git client for incremental updates of huge downloadable contents (DLC) published to a Git repository.
A client app can request with a commit or tree hash for a pack of wanted blobs and trees over Git Smart HTTP with the .NET built-in HttpClient instead of a full-blown Git client with a whole bunch of native executables.
This project begins with retrieving a Git pack using only efficient .NET 6.0 APIs. Further contribution is welcome.
using FlyByWireless.GitCore;
using HttpClient client = new(new AuthorizingHttpClientHandler());
var upa = client.GetUploadPackAsync(new("https://user:token@github.com/wegylexy/git-core.git/"));
await foreach (var p in upa)
{
var r = p.Key;
if (r.StartsWith("refs/heads/"))
{
Console.WriteLine($"branch {r.AsSpan(11)} -> commit {p.Value.ToHexString()}");
}
else if (r.StartsWith("refs/tags/") && r.EndsWith("^{}"))
{
Console.WriteLine($"tag {r.AsSpan()[10..^3]} -> commit {p.Value.ToHexString()}");
}
}Git remote capable of allow-reachable-sha1-in-want, shallow, and object-format=sha1:
- Remote URL:
https://github.com/wegylexy/git-core.git/(trailing/is required) - Username:
user - Token:
token
Local:
tree f0d3a70ceaa69fb70811f58254dc738e0f939eac100644 blob 1ff0c423042b46cb1d617b81efb715defbe8054d .gitattributes100644 blob 9491a2fda28342ab358eaf234e1afe0c07a53d62 .gitignore
Remote:
tree d56c74a8ae5d81ddfbebce18eea3c791fcea5e2d100644 blob 1ff0c423042b46cb1d617b81efb715defbe8054d .gitattributes(common)100644 blob 9491a2fda28342ab358eaf234e1afe0c07a53d62 .gitignore(common)040000 tree 6aaf05e6bf2af00e0574cc021ff72b29386e5eb1 GitCore.Tests- ...
100644 blob a03fb82afc9b189ffc24de772720456de61aee5e GitCore.sln040000 tree ccd51a743e683abbb13481be1c0384d9ce837d0c GitCore- ...
100644 blob d2489a28362500baaeefe5121a20fbe9b9145ead LICENSE100644 blob c9b283eddb6d8926508d645b15b671bc2802c232 README.md
Default capabilities includes thin-pack. The 2 blobs that local already has will not be packed.
using FlyByWireless.GitCore;
using HttpClient client = new(new AuthorizingHttpClientHandler());
using var response = await client.PostUploadPackAsync(new("https://user:token@github.com/wegylexy/git-core.git/"),
new
(
want: new ReadOnlyMemory<byte>[] { "d56c74a8ae5d81ddfbebce18eea3c791fcea5e2d".ParseHex() },
depth: 1,
have: new ReadOnlyMemory<byte>[] { "f0d3a70ceaa69fb70811f58254dc738e0f939eac".ParseHex() }
)
{
Capabilities = { "include-tag" }
}
);
await foreach (var uo in response.Pack) // for each unpacked object
{
var co = uo; // delta will re-assign current object
Triage:
switch (co.Type)
{
case ObjectType.Blob:
// TODO: save for every matching tree entry
break;
case ObjectType.Tree:
await foreach (var entry in co.AsTree())
{
switch (entry.Type)
{
case TreeEntryType.Blob:
// TODO: cache file name
break;
case TreeEntryType.Tree:
// TODO: create directory
break;
}
}
break;
case ObjectType.ReferenceDelta:
{
UnpackedObject baseObject;
// TODO: load base object
co = co.Delta(baseObject);
goto Triage;
}
break;
case ObjectType.Commit:
{
var treeHash = co.ToCommitContent().Tree;
// TODO: cache root tree
}
break;
case ObjectType.Tag when co.Type == ObjectType.Commit:
{
var tag = co.ToTagContent();
var commitHash = tag.Object;
var name = tag.Name;
var message = tag.Message;
// TODO: associate tag message to commit
}
break;
}
}
// TODO: delete files that is not in any tree