FAQ
Updated 11 Days AgoPublic

  • The FAQ will be populated from the most frequently asked questions
  • If your problem isn't listed here, contact your local IT support

What is c4science ?

C4 Science is a co-creation platform, curation and code sharing. This platform includes:

  • Version management systemdang
  • Common authentication to all Swiss universities to local + external collaborators
  • Social dimension (wikis, bug tracking, ...)
  • Code test system (continuous integration)

Is the data stored on a safe server within Switzerland?

We're using Switch Engines infrastructure in Lausanne Datacenter, and Zurich as backup. Data are strictly stored in Switzerland, and securely transit only within the SWITCH network.

Who has access to my user data?

You can see section 9.1 of the SLAs.

Who can use the platform?

Member of Swiss Universities have full acces to the platforms. External users can register with their Google, GitHub or a local account and be added to projects and repositories by members of Swiss Universities.

My repositories are hosted on git.epfl.ch. What happens to them?

Push will be deactivated at the end of the year. The service will stay read-only until the summer. After this, everything will be archived, and available on demand. It's recommended to migrate your repositories to c4science.

So there is now way to include automatically epfl groups?

You can use our import script to syncronize EPFL groups if your group is Public. This also works with any EPFL unit. Take a look in here: https://c4science.ch/source/phab-api/#getmystuph

I subscribed to the platform but do not have permission to create new repositories, what is happening?

If you belong to a Swiss University, you can create repositories, projects and wiki pages. You need to connect using the SwitchAAI authentication method, or you won't be able to create objects on c4science.

If you already registered for a local account and now your email is in use preventing you from registering with SwitchAAI, you have a couple of options:

  • Link SwitchAAI with your current account from the preferences, User icon on the upper rightSettingsAuthenticationExternal AccountsAdd External AccountSwitch AAI for Swiss Univercities
  • Or, change your main email for something else, then ask for this local account to be deactivated and finally register with SwitchAAI

I just want a simple Git repo: help!

here are the instructions. Do not hesitate to create a bug report if you think something should be added/changed.

How I can create a private repository that is nowhere visible and accessible?

The repositories created via these instructions are by default only visible/accessible by the creator.

I can't see my repositories, where are they ?

By default, the homepage only display repositories that are tagged with a Projet, you can create your own homepage using the Dashboard application.

You can find the repositories you created on your user page, by clicking the avatar on the top right area of the page.

I get a 403 error, what do I do?

If the error looks like this

fatal: unable to access 'https://c4science.ch/diffusion/997/simplegitrepo.git/': The requested URL returned error: 403

  • You don't have access to the repository (view or push)
  • You have not set up a VCS password. Have a look here.
  • Make sure you are using the correct c4science username, you can find it in you profile page
  • Password manager
    • If no username or pasword is asked during the request, you may have stored your credentials. Delete the credentials (depends on your operating system)
    • Mac OSX: The password is stored in the Keychain application in a internet password entry type for c4science.ch
    • Windows/LInux: By default the password is stored in plaintext in a file or with a password manager (keychain, windows password manager, ...).
    • You should be able to find the file or the way it's been stored using this command git config --global --get credential.helper. If you see credential.helper=manager or credential.helper=osxkeychainit means your OS is managing the password and there is something wrong stored there.

I don't understand what the policies (Visible/Editable/Pushable) are.

  • Visible means that the object (repository, project,...) can be accessed in read mode.
  • Editable by is the list of administrators (who can modify the object via the web interface)
  • Pushable by is for repositories and is the list of entities who can push to the repo

What are "dangerous changes"?

Here are several changes that are classified as dangerous by Phabricator:

  • delete a remote branch (git push --delete)
  • rewriting history (git push --force)

An administrator of the repository can allow dangerous changes, from the repo page:

ActionsManage RepositoryBasicsActionsAllow Dangerous Changes

It's best to Disable Dangerous Changes when you are done, so you don't delete files by mistake later on.

I use c4science to manage projects within my lab. Staff changes often. How do I give rights to a group?

C4science is global to all Swissuniversites members, thus you have to create a group in c4science to be referenced to. To do this, create a new project (or subproject) with icon type "Group" and add the appropriate users to it.

I need to store binary files, how do I do this?

Binary files, must not be hosted directly in a repository. GIT is not made for that. You can use GIT LFS (large file storage) for that, see https://c4science.ch/w/c4science/lfs/ your files will still be referenced in the repository, but hosted outside of it.

Quotas policies will be defined at the end of 2016. Usage is strictly monitored until then.

I would like to display a wiki page as homepage for a project instead of the Recent Activity feed.

Unfortunately, not yet -- you can add elements to the menu, task list, or modify the project description, which appears on the project page.

C4science only provides SSH links for SVN

HTTP access is only possible for Mercurial and GIT.

Is there a way to access a private repository without SSH key?

You can use VCS. Unauthenticated access must use HTTP instead of SSH, your repository view policy must be set to Public.

Permission Denied when using a DSA SSH key

DSA/DSS keys are obsolete and the SSH client prevents its usage by default on most platform. Our server accepts such keys, but you have to allow the client to send it by modifying your SSH configuration like so:

Host c4science.ch
    PubkeyAcceptedKeyTypes +ssh-dss

It is advised that you create an RSA key instead, of a minimum size of 2048-bit.

Permission denied using SSH

Wrong private key filename

It's possible that your key have a non standard name the your SSH client cannot find. By default, the client will look for id_rsa, id_dsa files. If you customized your key name, please specify your key in the client configuration in ~/.ssh/config like so:

Host c4science.ch
    User git
    IdentityFile /home/aubort/.ssh/id_rsa_phab

No SSH agent

  • It's possible that your ssh-agent isn't running
  • Here's how to start a new ssh agent and add your ssh key to it
eval `ssh-agent -s`
ssh-add ~/.ssh/id_rsa

Invalid Shibboleth Session

  • You can't log in using SwitchAAi with Invalid Shibboleth Session` error
  • This can have multiple root causes, the most usual cause is the lack of email in the Shibboleth authentication
  • Make sure you have an email associated with your university account

Why can't I delete anything on c4science ?

fatal: The remote end hung up unexpectedly

  • There may be multiple reasons for this error, bug in general it's that your push is too big (>= 256MB) and you're using HTTP
  • Here are some possibilities
    • Use SSH instead of HTTP which doesn't have limit, see Setting up SSH keys
    • You can tweak how GIT is sending the push so it doesn't break our servers by using this command
git config http.postBuffer 128000000

It's also a good idea to remove big files from your repository using BFG and add them back with GIT LFS, see Large File Storage (LFS) in GIT, or simply use LFS from now on.

WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!

  • If you have this message, make sure the key fingerprint is one of the following,
2048 SHA256:uQ/5ZR62kzgdcmhjzmULN6wuW8J1iXWA5kNibUP9bcU c4science.ch (RSA)
256 SHA256:hlDsRQ9XEGLOM9g9tdUaigIyDNuCD80x2G2RcdJOLRo c4science.ch (ECDSA)
256 SHA256:u0EBwdqWNPdKxm4JYi8M7YfYtpl8RPG96E28bdSJ3R0 c4science.ch (ED25519)
  • If this is not the case, there's a big problem. Please contact your local IT support

This file is binary - blank page on the repository file browser

  • If you have a file with a non-UTF8 character, the file will be treated as Binary. It'll then be hidden in the web interface
  • Either use plain ASCII or UTF-8 encoding
  • You can convert your file to UTF-8 using iconv, where ISO-8859-16 is the source encoding
iconv -f iso-8859-16 -t utf8 -o input.txt input.txt

You can not select this edit policy, because you would no longer be able to view the object.

When creating a Project with the default Policies (Project Members), you must add yourself to the Initial Members, otherwise you'll not be able to Edit the project you just created.

Last Author
aubort
Projects
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