CUCC Expedition: Online repositories

Version-controlled repositories

git logo

The repositories

All the expo data is contained in 4 repositories or repos at

If you want to use your own laptop to interact directly with the repos then a basic laptop or a survey laptop is not enough: you need an expo bulk update laptop.

From the command line, to clone a repo, you will do this git clone ssh:// see the quick reminders for using git for the rest of them.

Use the online view of these!

These online webpages (links above) give a much clearer view of what is going on than many git tools you may be using on your machine.

Have a look at the version history of the drawings to look at progress on getting the recent surveys uploaded, and who has been doing what on the website and handbook.

For an example, see this simple edit.

Cheat lists and quick reminders

Version control system

We use a distributed revision control system (git) for all the important data.

Note that we just use git: not GitHub, not GitLab, just git.

This allows many people to edit and merge their changes at the same time. This includes people still on expo and those who have returned to the UK. Also anyone who is up to date can take their laptop somewhere (e.g. topcamp) and enter data even if they have no Internet access, and the updates will be merged when they get back to civilization.

We use a version control system because this keeps track of all changes so we can roll back mistakes. We also have multiple copies of the data on multiple machines for safety.

We use git because it is now the industry standard. In the past we have used cvs, subversion and mercurial.

A version control system is inefficient for photos, GPS tracks and scanned survey notes which are large files that do not get modified. These are kept as a plain directory of files /expofiles/.

Uploading cave survey data, scanned notes or Therion/Tunnel drawings

You do not need to know about the version control system for several common cave data surveying tasks.

The online system has forms to allow you to upload these, and it invokes git behind the scenes to keep everything tidy. However these capabilities are being used for the first time on the 2022 expo so be prepared for things to break, e.g. if two people try to do the same thing at the same time.

Reading and cloning

You can read or clone these repos without any control, but to write ("push") to them you will need to use ssh:// and set up the key exchange.

NOTE: when using git to path to a repository, always use user 'expo' as the login user (ssh://expo@...) even though within git you will be identified by your own ssh key name. This is because file permissions on the server require this.

So cavers wanting to do sophisticated management of their cave survey data (i.e. not just simple uploads) will have to use a machine on which they key is already set up. The expo laptop lives in the potato hut during expo and it is sometimes joined by the laptop 'aziraphale'. These are both loaned machines running Linux. If you want to use your own laptop then a basic laptop or a survey laptop is not enough: you need a bulk update laptop.

Return to Expo Data Maintenance manual
Return to Expo Systems Overview