# gitobj
[![](https://travis-ci.org/git-lfs/gitobj.svg?branch=master)](https://travis-ci.org/git-lfs/gitobj) [![](https://godoc.org/github.com/git-lfs/gitobj?status.svg)](https://godoc.org/github.com/git-lfs/gitobj)
Package `gitobj` reads and writes loose and packed Git objects.
## Getting Started
To access a repository's objects, begin by "opening" that repository for use:
```go
package main
import (
"github.com/git-lfs/gitobj"
)
func main() {
repo, err := gitobj.FromFilesystem("/path/to/repo.git", "")
if err != nil {
panic(err)
}
defer repo.Close()
}
```
You can then open objects for inspection with the [`Blob()`][blob],
[`Commit()`][commit], [`Tag()`][tag], or [`Tree()`][tree] functions:
[blob]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.Blob
[commit]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.Commit
[tag]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.Tag
[tree]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.Tree
```go
func main() {
repo, err := gitobj.FromFilesystem("/path/to/repo.git", "")
if err != nil {
panic(err)
}
defer repo.Close()
commit, err := repo.Commit([]byte{...})
if err != nil {
panic(err)
}
}
```
Once an object is opened or an instance is held, it can be saved to the object
database using the [`WriteBlob()`][wblob], [`WriteCommit()`][wcommit],
[`WriteTag()`][wtag], or [`WriteTree()`][wtree] functions:
[wblob]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.WriteBlob
[wcommit]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.WriteCommit
[wtag]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.WriteTag
[wtree]: https://godoc.org/github.com/git-lfs/gitobj#ObjectDatabase.WriteTree
```go
func main() {
repo, err := gitobj.FromFilesystem("/path/to/repo.git", "")
if err != nil {
panic(err)
}
defer repo.Close()
commit, err := repo.Commit([]byte{...})
if err != nil {
panic(err)
}
commit.Message = "Hello from gitobj!"
commit.ExtraHeaders = append(commit.ExtraHeaders, &gitobj.ExtraHeader{
K: "Signed-off-by",
V: "Jane Doe <jane@example.com>",
})
if _, err := repository.WriteCommit(commit); err != nil {
panic(err)
}
}
```
### Packed Objects
Package `gitobj` has support for reading "packed" objects (i.e., objects found
in [packfiles][1]) via package `github.com/git-lfs/gitobj/pack`. Package `pack`
implements searching pack index (`.idx`) files and locating the corresponding
delta-base chain in the appropriate `pack` file. It understands both version
1 and version 2 of the packfile specification.
`gitobj` will always try to locate a loose object first. If a loose object
cannot be found with the appropriate SHA-1, the repository's packfile(s) will
be searched. If an object is located in a packfile, that object will be
reconstructed along its delta-base chain and then returned transparently.
### More information
For more: https://godoc.org/github.com/git-lfs/gitobj.
## License
MIT.
[1]: https://git-scm.com/book/en/v2/Git-Internals-Packfiles