Working with Git often involves looking into past revisions of your code to understand changes, recover lost work, or inspect older versions of files. Git provides various commands to help retrieve a single file from a specific revision. This article will guide you through several methods to accomplish this, ensuring you can access the file’s history effectively.

Prerequisites

• Git Installed
• Basic Git Knowledge

Methods for Retrieving a Single File

1. Using git show

The git show command allows you to view the content of a file at a specific revision and can be redirected to save the file.

Retrieve File Content

To view the content of file.txt from a specific commit (e.g., abcd123):

git show abcd123:file.txt

Save File Content

To save the content to a file:

git show abcd123:file.txt > file.txt

2. Using git checkout

The git checkout command can be used to update the working directory with the content of a file from a specific revision.

Retrieve and Replace File

To replace the current file.txt with the version from commit abcd123:

git checkout abcd123 -- file.txt

Save to a Different Location

To avoid overwriting the existing file, you can specify a different path:

git checkout abcd123 -- file.txt
mv file.txt path/to/destination/file.txt

3. Using git restore

Introduced in Git 2.23, git restore is a more intuitive alternative to git checkout for restoring files from a specific revision.

Restore File

To restore file.txt from commit abcd123:

git restore --source=abcd123 --staged --worktree -- file.txt

Save to a Different Location

To save it to another location without staging:

git restore --source=abcd123 --worktree -- file.txt
mv file.txt path/to/destination/file.txt

4. Using git diff with Redirection

You can use git diff to compare a specific revision of a file with the current version and then apply the changes to retrieve the file.

Generate Diff

To generate a diff for file.txt from commit abcd123:

git diff abcd123:file.txt > changes.patch

Apply Diff

To apply the patch and retrieve the file content:

git apply changes.patch

5. Using git archive

The git archive command can create an archive of the file from a specific commit, which can then be extracted.

Create Archive

To create an archive containing file.txt from commit abcd123:

git archive --format=tar --prefix=old-version/ abcd123 file.txt | tar -x -C path/to/destination

This will extract the file to path/to/destination/old-version/file.txt.

Examples

Example 1: Retrieve a File Using git show

Suppose you want to retrieve README.md from commit f3e1a0.

1. View Content:

git show f3e1a0:README.md

2. Save to File:

git show f3e1a0:README.md > README_old.md

Example 2: Retrieve a File Using git checkout

To get config.yml from commit e7a5d2:

1. Replace Current File:

git checkout e7a5d2 -- config.yml

2. Save to Different Path:

git checkout e7a5d2 -- config.yml
mv config.yml old_versions/config_e7a5d2.yml

Example 3: Retrieve a File Using git restore

To restore index.html from commit 5b6f8a:

1. Restore and Stage File:

git restore --source=5b6f8a --staged --worktree -- index.html

2. Save to Another Location:

git restore --source=5b6f8a --worktree -- index.html
mv index.html archived_versions/index_5b6f8a.html

Example 4: Retrieve a File Using git archive

To get main.py from commit 2a3b9c:

1. Create and Extract Archive:

git archive --format=tar --prefix=archive/ 2a3b9c main.py | tar -x -C backup/

This command extracts main.py to backup/archive/main.py.