( The following presumes you have installed Docker on your machine )

Lets say you want to execute a command using something like the jq json parsing program, but jq is not installed on your machine. You could install jq, but perhaps for some reason you'd prefer not to. This could be for a variety of reasons

The run_in_alpine_with function in the snippet above can help

It lets you easily run commands using packages you'd rather not install. It runs your command inside a tiny alpine Docker container after installing your required package(s) into it. Any available Alpine packages can be used

You can add the function to your ~.zshrc or ~.bashrc

After adding it, restart your terminal session

Then you can paste a command like this into your terminal:

run_in_alpine_with jq <<'EOF'
  echo '{"name": "Alice", "age": 30}' | jq -r '.name'
EOF

The example above outputs Alice

Or you could run it like this:

run_in_alpine_with curl <<'EOF'
  curl -s https://api.github.com/users/montehurd
EOF

Which outputs something like this:

{
  "login": "montehurd",
  "id": 3143487,
  "node_id": "MDQ6VXNlcjMxNDM0ODc=",
  "avatar_url": "https://avatars.githubusercontent.com/u/3143487?v=4",
  "gravatar_id": "",
  "url": "https://api.github.com/users/montehurd",
  "html_url": "https://github.com/montehurd",
  "followers_url": "https://api.github.com/users/montehurd/followers",
  "following_url": "https://api.github.com/users/montehurd/following{/other_user}",
  "gists_url": "https://api.github.com/users/montehurd/gists{/gist_id}",
  "starred_url": "https://api.github.com/users/montehurd/starred{/owner}{/repo}",
  "subscriptions_url": "https://api.github.com/users/montehurd/subscriptions",
  "organizations_url": "https://api.github.com/users/montehurd/orgs",
  "repos_url": "https://api.github.com/users/montehurd/repos",
  "events_url": "https://api.github.com/users/montehurd/events{/privacy}",
  "received_events_url": "https://api.github.com/users/montehurd/received_events",
  "type": "User",
  "site_admin": false,
  "name": null,
  "company": "Wikimedia Foundation",
  "blog": "",
  "location": "San Francisco, US",
  "email": null,
  "hireable": null,
  "bio": "software engineer @wikimedia",
  "twitter_username": null,
  "public_repos": 14,
  "public_gists": 7,
  "followers": 23,
  "following": 3,
  "created_at": "2012-12-28T17:58:53Z",
  "updated_at": "2024-08-22T21:18:13Z"
}

This demonstrates how to pipe that same command as a string to the function. It can require more quote escaping than the other method though:

echo "curl -s https://api.github.com/users/montehurd" | run_in_alpine_with curl

Here you can see how to install and use multiple packages in the Alpine container:

run_in_alpine_with curl jq <<'EOF'
  curl -s https://api.github.com/users/montehurd | jq -r '.bio'
EOF

Which should output software engineer @wikimedia

Note: you can remove >/dev/null 2>&1 from the function and restart your terminal session to debug package installation if you run into any issues