How to Use In-Memory Repositories¶

For tasks like transient analysis, code generation, or CI verification, you may want to clone and interact with a repository without leaving files on the host disk. GTB supports this via the SourceMemory strategy.

1. Initialize a Memory Repository¶

Use NewRepo and OpenInMemory to clone a repository into RAM using memfs.

import (
    "github.com/phpboyscout/gtb/pkg/props"
    "github.com/phpboyscout/gtb/pkg/vcs"
)

func analyzeRepo(p *props.Props, url string) error {
    repo, err := vcs.NewRepo(p)
    if err != nil {
        return err
    }

    // Clone into memory
    _, _, err = repo.OpenInMemory(url, "main")
    if err != nil {
        return err
    }

    // The repository is now resident in memory
    return nil
}

2. Inspect Files In-Memory¶

You can walk the tree or check for specific files without touching the disk.

exists, err := repo.FileExists("cmd/root.go")
if exists {
    file, _ := repo.GetFile("cmd/root.go")
    // Use file.Reader() to read content
}

3. Hydrating the Application Filesystem¶

If you need to move files from the in-memory Git storage to your application's primary filesystem (e.g., for processing or output), use AddToFS.

// repo.AddToFS(target_fs, git_file, target_path)
err := repo.AddToFS(p.FS, gitFile, "/tmp/analysis/root.go")

4. Why use In-Memory?¶

• Cleanup: No need to manage temporary directories or track files for deletion.
• Speed: I/O is restricted to memory, making it significantly faster for small-to-medium repositories.
• Security: Reduces the risk of leaving sensitive source code on shared disk space or CI environments.