can't add git submodule to repository

Question

(Predominantly a Git question, but may be relevant to other PyroCMS users)

I have a local repository of PyroCMS - the repo is a clone of a github fork of the main project. I also have a PyroCMS module, which is also a local clone of a github fork of that project.

I've put them both in separate directories.

~/Dropbox/websites/pyrocmscommunity-test/
~/Dropbox/github/PyroDatabase/

I want to add PyroDatabase as a submodule of pyrocmscommunity-test, so I can pull updates from github, keep track of my own changes etc.

I tried to do this by going to the top of the working tree and doing:

git submodule add ../../github/PyroDatabase/ addons/shared_addons/modules/

but it didn't complete properly:

Cloning into 'addons/shared_addons/modules/database'...
ssh_exchange_identification: Connection closed by remote host
fatal: The remote end hung up unexpectedly

I don't understand this as I didn't specify an SSH connection, I just wanted to use the local repo. What is it trying to connect to and why?

Also, now, whenever I repeat the command, I get this:

'addons/shared_addons/modules' already exists in the index

But I don't understand this as there is no .gitmodules file and no mention of the modules files in .gitconfig either.

What am I doing wrong and how do I reset things?

Thanks, William

Answer 1

When specifying relative URLs for submodule location, Git takes it relatively to the origin (here Github) URL of the current projet, and not relatively to the project location on filesystem. This is because a submodule is a permanent pointer to a remote location. Here Git tries to contact the origin github repository with two levels up, which is an incorrect URL.

As for the second error Git has created an entry in the staging area of your index, and it must be removed (unstaged) with

git rm -r addons/shared_addons/modules

Then retry with the absolute path to your clone:

git submodule add $HOME/Dropbox/github/PyroDatabase/ addons/shared_addons/modules/

Anyway adding a local clone of your project as a submodule of itself is weird, since submodules are meant to be a different repo of the containing project. Why not keep track of local and origin commits in standard Git fashion?

Answer 2

What version of git are you running? You probably cannot run the command again because the directory structure you specified has been staged. You can reset things like this (be careful with this command):

$ git status # check what has been changed
$ git reset --hard HEAD # destroy all working copy changes

A really useful way to debug what's going on with git is to set GIT_TRACE=1. So, try running the command again once you've cleaned up like this:

$ GIT_TRACE=1 git submodule add ../../github/PyroDatabase/ addons/shared_addons/modules/