git "ping": check if remote repository exists

Question

I'd like to know whether a remote repository exists. Here's what I came up with:

git ls-remote -h "$REPO_URL" &> /dev/null

Is there any better way?

score 106 · Accepted Answer · edited Apr 19 '22 at 15:29

106

I think the git ls-remote command is pretty much made for that purpose.

edited Apr 19 '22 at 15:29

Zebiano

103
3

answered Jan 01 '11 at 12:08

Peter Eisentraut

7,480

score 23 · Answer 2 · edited Oct 29 '14 at 14:30

23

If you use --exit-code argument you can skip sending output to null. It will return something only in case of error.

Also, you can use -h argument to show only heads references.

git ls-remote --exit-code -h "$REPO_URL"

edited Oct 29 '14 at 14:30

Jawa

3,679

answered Oct 29 '14 at 14:18

Oleksiy Chystoprudov

331

vaab · Answer 3 · 2022-08-10T16:42:55.000

TL;DR:

git ls-remote is the way, here is a shell-ready function for quick access:

  ## Returns errlvl 0 if $1 is a reachable git remote url 
  git-remote-url-reachable() {
      git ls-remote "$1" CHECK_GIT_REMOTE_URL_REACHABILITY >/dev/null 2>&1
  }

Usage:

if git-remote-url-reachable "$url"; then
   ## code
fi

What is it doing ?

This is just a convenient mash-up of all the comments/solutions previously stated with some small tweaks, a bash copy-paste ready function and usage code sample to make it crystal clear. You'll note that:

it limits output as the reference checked (here CHECK_GIT_REMOTE_URL_REACHABILITY) is probably nonexistent on the remote server, and git doesn't have anything to answer back. We rely on the fact that git will still exit with error-level 0 on non-existing ref. The only difference here is that there are slightly less output to transfer on the network compared to ask for HEAD (and much less than not asking for a ref or even limiting to only heads), and this is also less output to cast in /dev/null (but this last one is taking negligible time anyway)
the name of the ref checked that was chosen (which is CHECK_GIT_REMOTE_URL_REACHABILITY) makes it clear we are probing for existence, this could help if you want to be polite with the administrators of the server you are probing and give them a chance to understand why they receive these probes if they monitor anything.

score 4 · Answer 4 · answered Aug 23 '13 at 06:00

4

You can narrow output by using something like git ls-remote "$REPO_URL" HEAD

answered Aug 23 '13 at 06:00

ony

231

score 2 · Answer 5 · answered Sep 24 '21 at 18:26

2

By disabling asking for credentials, then listing the remote head only:

export GIT_TERMINAL_PROMPT=0
git ls-remote "${repo}" HEAD &> /dev/null

answered Sep 24 '21 at 18:26

Alberto Salvia Novella

360

Gabriel Staples · Answer 6 · 2022-08-09T21:28:12.870

The fastest and most-reliable way I've found in bash is this:

if timeout 30s git ls-remote --tags > /dev/null 2>&1; then
    # Note: it takes 2~4 sec to get to here.
    echo "git server IS available"
else
    # Note: it takes 30 seconds (as specified by `timeout`) to get to here.
    echo "git server is NOT available"
fi

Optionally increase the timeout 30s value to a larger number of seconds if your server is unable to respond under normal conditions within that amount of time.

For a full and detailed explanation, see my main answers here:

git "ping": check if remote repository exists

6 Answers6