Mix fails to clone from GitHub over HTTPS via 'mix deps.get'

Aha! I recently enabled two-factor authentication, which might be why this is happening:

If you have enabled two-factor authentication, or if you are accessing an organization that uses SAML single sign-on, you must provide a personal access token instead of entering your password for HTTPS Git. (Source)

You can create a personal access token and use it in place of a password when performing Git operations over HTTPS with Git on the command line or the API. (Source)

I wasn’t aware of that until now.

Since GitHub recommends HTTPS over SSH, I’ll get that working instead.

Edit:

So, I fixed two-factor authentication, and the problem still persisted. After much head-scratching, I decided to try in Apple’s “Terminal” app, instead of iTerm.

Lo and behold; cloning over HTTPS worked like a dream.

After some more digging, I found the culprit: The app “Little Snitch” (network filter) was blocking iTerm. Adding an exception to the network filter was all I needed to do

I know it’s been years but I’m going to chime in here as well just in case anyone runs into the specific issue I was having…

Any git SSH commands started prompting me for my key’s password every time despite having already added my key to an agent via ssh-add.

Then I remembered that earlier today I was setting up the 1Password CLI and configuring it for SSH. Part of the instructions say to add something like:

Host *
  IdentityAgent "~/Library/Group Containers/12345ABCDEF.com.1password/t/agent.sock"

To your SSH config file: ~/.ssh/config

The rest of my SSH config looked like this:

Host *.github.com
  AddKeysToAgent yes
  UseKeychain yes
  IdentityFile ~/.ssh/id_ed25519

Host *.gitlab.com
  AddKeysToAgent yes
  UseKeychain yes
  IdentityFile ~/.ssh/id_ed25519

So my silly self had inadvertently told SSH to always go through the 1Password socket for every host… I commented that out and now I’m good to go…