In an earlier post, I covered how to add and remove remote repositories. Now that we’ve told our local git repo where all these remotes are, now what?

Push

We want to share all the changes we’ve made on our project with our collaborators. Or we just want a backup incase our computer catches fire. The next step is to push the changes we’ve made to our remote repo. The push command is pretty safe and it is pretty hard to mess anything up by using it.

Here is the general outline of the command:

git push <alias>

Typically, we will just be pushing to origin, the default remote repository:

git push origin

Sometimes, when we have multiple branches, we might need to specify which branch we want to push to the remote:

git push origin master

And actually, this formula can be generalized as:

git push <alias> <branch name>

With this, we can push to any remote (that we are authorized to access) and specify any branch we like!

Fetch

Our collaborators have been hard at work! We want to update our local repo with the changes they’ve pushed to our shared remote. If we want to download all of the changes, but not merge them into your files just yet, we want to use the ‘fetch’ command. This is the ‘safer’ command, because we can check on the changes before merging them into our own files.

If we only have one remote:

git fetch

If we have more than one remote:

git fetch <alias>

If we want to download from all remotes:

git fetch --all

Now we have all of our changes from the remote on our local machine, but our local files haven’t been updated yet.

I like to take a look at what git thinks is happening.

git diff <branch-name> <remote-alias>/<branch-name>

This should show us the changes that will be made to our files. Assuming everything looks about right, it’s time to merge.

Check we are on the correct branch:

git branch

Then merge:

git merge <remote-alias>/<branch-name>

Pull

Sometimes referred to as a ‘fast forward’, the ‘pull’ command does a ‘fetch’ and a ‘merge’ all in one command. I think of this as THE DANGER ZONE. Sometimes, it is exactly what I want, like when I am the only one making commits to a branch or repo, or I know that I want to merge all the changes in the remote with my own local changes. If this is the case, the pull command makes getting updates from the remote really easy.

git pull <alias> <branch-name>

And we’re done!

Other Resources:

• I found this blog post on git fetch vs git pull to be very helpful. Spoiler: git fetch is the way to go!
• As always, obsessively reading the documentation on push, fetch, and pull was really helpful.
• And many thanks go Jeff Felchner for giving a talk at MakerSquare on using Git beyond the basics! Remember kids, NO FORCE PUSH!

Git and version control are some of the wierdest and funnest things I’ve been introduced to. I love the idea of taking continuous snapshots of the small steps of my work, and then being able to sift through them and pick the ones I want. I think I’m still at a fairly basic level, but within that context, I’ve learned so much!

Remote Repositories

Remote repositories are basically copies of your git repo that are not stored on your hard drive. This seems kind of obvious, but didn’t really click for me until I learned that you could have as many remote repositories (remotes, for short) as you want!

Step 1: Take a look at the remote repositories you already have.

git remote -v

You will see a list that looks something like this:

origin https://github.com/cglinka/urdb-1.git (fetch)
origin https://github.com/cglinka/urdb-1.git (push)

Or like this, if you have multiple remotes already set:

mks https://github.com/makersquare/urdb.git (fetch)
mks https://github.com/makersquare/urdb.git (push)
origin https://github.com/cglinka/urdb-1.git (fetch)
origin https://github.com/cglinka/urdb-1.git (push)

You can see the remote name (or ‘alias’, if you want to get technical about it) followed by the URL that actually describes the location of each remote repository.

All of my remotes are on GitHub, but you can have remotes on other servers, or so I’m told. I have not tried to set up my own git server yet. :D

NOTE: The repo you clone from and/or the first remote you add will by default be called your origin. So when you are reading tips and tricks about Git, origin is just your ‘default’ remote alias, which may or may not be true for your particular repo. This may or may not cause a lot of confusion and/or frustration, but checking your remote names/aliases will save you a lot of troubleshooting time.

Step 2: Add a new remote.

git remote add <ALIAS> <url>

Fill in ALIAS with the name you want to use to access that remote. You can’t use origin if you already have an origin assigned. I try and give them easy-to-remember names based on the GitHub username. For the last several weeks, we’ve been working on the same repos in class, with new branches every day for that day’s lesson. Instead of making a million folders with a million copies of the same repo, I added a second remote as ‘mks’ that pointed to the correct repo on the makersquare account so I could just update my local copy of the repo every day! I added a third remote that pointed to my partner’s repo of the same assignment.

Step 3: But I want to change the remote that origin points to!

It’s cool, you can do that! First, remove the current origin:

git remote rm origin

Then, check make sure you removed the origin:

git remote -v

Last, add the new origin;

git remote add origin <URL>

And just to be sure, check your remotes again:

git remote -v

Ta-dah! New origin added!

I think one of the first things you learn in git is the

git diff

command. This one is really important for me, because I forget exactly what I’ve changed since I last committed. But sometimes, I forget to run

git diff

before I add my files to the staging area. Whoops!

I feel like I should have figured this out sooner (that’s how learning works, right? obvious once you know it), but there is a very nice command that fixes this problem for me!

git diff --cached

show the git diff for files I’ve already staged! Huzzah! My commit messages will never be a series of “Ummmmm, I don’t remember what I just did.”