Git refs¶

A git ref (reference) is a human-readable name that points to a commit ID. With refs, you do not need to remember long SHA-1 hashes.

Where git stores refs¶

Git stores most refs as small files under .git/refs/. Each file holds the hash of one commit.

A remote-tracking branch is a local copy of the state of a branch on a remote.

cat .git/refs/heads/main

Git can also pack many refs into one file, .git/packed-refs. If you do not find a ref under .git/refs/, look in that file.

HEAD is a special ref. It usually points to another ref (the current branch), not to a commit.

A symbolic ref is a ref that points to another ref. HEAD is the most common example.

cat .git/HEAD
# ref: refs/heads/main

git symbolic-ref HEAD
# refs/heads/main

If HEAD points directly to a commit, you are in a detached HEAD state. See Detached HEAD.

List all refs:

git show-ref

Show the commit that a ref points to:

git rev-parse main
git rev-parse origin/main

List refs with a custom format:

git for-each-ref --format='%(refname) %(objectname:short)' refs/heads/

The targetRevision field in an Argo CD Application accepts a ref, such as a branch or a tag. It also accepts a commit SHA.

spec:
  source:
    repoURL: https://provider.com/organization/repository.git
    targetRevision: v1.0.0
    path: manifests