We're still in our working directory:
import os top_dir = os.getcwd() git_dir = os.path.join(top_dir, 'learning_git') working_dir = os.path.join(git_dir, 'git_example') os.chdir(working_dir) working_dir
So far, all our work has been on our own computer. But a big part of the point of version control is keeping your work safe, on remote servers. Another part is making it easy to share your work with the world In this example, we'll be using the "GitHub" cloud repository to store and publish our work.
If you have not done so already, you should create an account on GitHub: go to GitHub's website, fill in a username and password, and click on "sign up for GitHub".
Creating a repository¶
Ok, let's create a repository to store our work. Hit "new repository" on the right of the github home screen.
Fill in a short name, and a description. Choose a "public" repository. Don't choose to initialize the repository with a README. That will create a repository with content and we only want a placeholder where to upload what we've created locally.
Paying for GitHub¶
For this course, you should use public repositories in your personal account for your example work: it's good to share! GitHub is free for open source, but in general, charges a fee if you want to keep your work private.
In the future, you might want to keep your work on GitHub private.
Students can get free private repositories on GitHub, by going to GitHub Education and filling in a form (look for the Student Developer Pack).
UCL pays for private GitHub repositories for UCL research groups: you can find the service details on the Research Software Development Group's website.
Adding a new remote to your repository¶
Instructions will appear, once you've created the repository, as to how to add this new "remote" server to your repository, in the lower box on the screen. Mine say:
%%bash git remote add origin firstname.lastname@example.org:UCL/github-example.git
%%bash git push -uf origin main # I have an extra `f` switch here. #You should copy the instructions from YOUR repository.
To github.com:UCL/github-example.git + e302acd...831706e main -> main (forced update)
branch 'main' set up to track 'origin/main'.
The first command sets up the server as a new
Git, unlike some earlier version control systems is a "distributed" version control system, which means you can work with multiple remote servers.
Usually, commands that work with remotes allow you to specify the remote to use, but assume the
origin remote if you don't.
git push will push your whole history onto the server, and now you'll be able to see it on the internet! Refresh your web browser where the instructions were, and you'll see your repository!
Let's add these commands to our diagram:
message=""" Working Directory -> Staging Area : git add Staging Area -> Local Repository : git commit Working Directory -> Local Repository : git commit -a Staging Area -> Working Directory : git checkout Local Repository -> Staging Area : git reset Local Repository -> Working Directory: git reset --hard Local Repository -> Remote Repository : git push """ from wsd import wsd %matplotlib inline wsd(message)
Playing with GitHub¶
Take a few moments to click around and work your way through the GitHub interface. Try clicking on 'index.md' to see the content of the file: notice how the markdown renders prettily.
Click on "commits" near the top of the screen, to see all the changes you've made. Click on the commit number next to the right of a change, to see what changes it includes: removals are shown in red, and additions in green.
%%writefile lakeland.md Lakeland ======== Cumbria has some pretty hills, and lakes too.
Lakeland ======== Cumbria has some pretty hills, and lakes too.
%%bash --no-raise-error git commit -am "Try to add Lakeland"
On branch main Your branch is up to date with 'origin/main'. Untracked files: (use "git add <file>..." to include in what will be committed) __pycache__/ lakeland.md wsd.py nothing added to commit but untracked files present (use "git add" to track)
This didn't do anything, because we've not told git to track the new file yet.
%%bash git add lakeland.md git commit -am "Add lakeland"
[main 8343def] Add lakeland 1 file changed, 4 insertions(+) create mode 100644 lakeland.md
Ok, now we have added the change about Cumbria to the file. Let's publish it to the origin repository.
%%bash git push
To github.com:UCL/github-example.git 831706e..8343def main -> main
Visit GitHub, and notice this change is on your repository on the server. We could have said
git push origin to specify the remote to use, but origin is the default.
What if we change both files?
%%writefile lakeland.md Lakeland ======== Cumbria has some pretty hills, and lakes too Mountains: * Helvellyn
%%writefile index.md Mountains and Lakes in the UK =================== Engerland is not very mountainous. But has some tall hills, and maybe a mountain or two depending on your definition.
%%bash git status
On branch main Your branch is up to date with 'origin/main'. Changes not staged for commit: (use "git add <file>..." to update what will be committed) (use "git restore <file>..." to discard changes in working directory) modified: index.md modified: lakeland.md Untracked files: (use "git add <file>..." to include in what will be committed) __pycache__/ wsd.py no changes added to commit (use "git add" and/or "git commit -a")
These changes should really be separate commits. We can do this with careful use of git add, to stage first one commit, then the other.
%%bash git add index.md git commit -m "Include lakes in the scope"
[main e600228] Include lakes in the scope 1 file changed, 4 insertions(+), 3 deletions(-)
Because we "staged" only index.md, the changes to lakeland.md were not included in that commit.
%%bash git commit -am "Add Helvellyn"
[main cea1ebf] Add Helvellyn 1 file changed, 4 insertions(+), 1 deletion(-)
%%bash git log --oneline
cea1ebf Add Helvellyn e600228 Include lakes in the scope 8343def Add lakeland 831706e Revert "Add a lie about a mountain" 2a2f993 Change title 87abe73 Add a lie about a mountain 55d7862 First commit of discourse on UK topography
%%bash git push
To github.com:UCL/github-example.git 8343def..cea1ebf main -> main
message=""" participant "Cleese's remote" as M participant "Cleese's repo" as R participant "Cleese's index" as I participant Cleese as C note right of C: vim index.md note right of C: vim lakeland.md note right of C: git add index.md C->I: Add *only* the changes to index.md to the staging area note right of C: git commit -m "Include lakes" I->R: Make a commit from currently staged changes: index.md only note right of C: git commit -am "Add Helvellyn" C->I: Stage *all remaining* changes, (lakeland.md) I->R: Make a commit from currently staged changes note right of C: git push R->M: Transfer commits to Github """ wsd(message)