Automate asciinema screencasts

[hexagonrecursion]

Fix #2909

Manually generating asciinema screencasts is:

1. Tedious
2. Time consuming
3. Inconsistent
4. Error prone
5. Has to be done from scratch every time you want to change something

This is my attempt to automate the process

TODO:

• automate the advanced usage screencast
• automate the installation screencast
• dynamically echo the current borg version
• add color (if you want it)
• add a more convincing emulation of data-to-backup
• fake a remote system via /etc/hosts
• figure out how to fake a remote system. I think docker-compose might help me here
  This is needed to run the following command from the basic usage example:

  borg init --encryption=repokey borgdemo@remoteserver.example:./demo
  

  I have figured it out: map remoteserver.example to localhost in /etc/hosts

[hexagonrecursion]

I have found a good way to implement this - isolate the example form the host by using a docker container. This way I get a disposable system I can freely butcher modify as needed to make the examples work.

[ThomasWaldmann]

Hmm, I usually don't use docker. Just ssh to localhost to simulate a "remote" repo?

[hexagonrecursion]

It's not just the remote example. I need some safe place to make a mess without messing up the machine of the developer doing the recording:

1. The installation example needs to actually install borg somewhere
2. A faithful recreation of the basic usage example depends on /media/backup/borgdemo existing
3. The remote example needs to ssh somewhere. In general I can't count on ssh being installed or configured a certain way on the developer machine. Requiring the developer to configure it manually defeats much of the benefit of automation. Automatically installing packages and changing configuration is likely to lead to all sorts of trouble unless it is done in some kind of disposable sandbox.
4. The installation example needs wget, gpg and sudo. The basic example requires diff. What if diff, wget, gpg or sudo are missing?
5. The installation example sudo w/o a password. Even if sudo is installed and the current user can use it, there is a manual step of pre-entering the password before starting the recording

Using docker seemed like a neat way to make a mess and clean it up.

I usually don't use docker

What do you use instead?

[hexagonrecursion]

I usually don't use docker

I have been in this boat too, but now I am quite comfortable with it and the power is worth the learning curve.

[ThomasWaldmann]

I use VMs and vagrant (for borg mainly for automated platform testing).

[hexagonrecursion]

I guess I'll have to learn vagrant then.

[hexagonrecursion]

@ThomasWaldmann I have found some time to work on this. Reimplemented installation and basic usage via Vagrant. Take a look.

[ThomasWaldmann]

Thanks! Will do, but likely after 1.2.0 release.

[hexagonrecursion]

This should be ready now.

[ThomasWaldmann]

Found / fixed some typos (squashed the fixes into the changeset where they were introduced).

[ThomasWaldmann]

Next thing I will try is to adapt this for borg2 (we definitely need new screencasts there as a lot of stuff changed).

If I succeed, shall I just push the stuff to your branch? Guess you'ld need to open a new PR then against the borg2 branch.

Update: hmm, no, I'll just update it to borg 1.2.1 and merge it into master. borg2 update can be done later.

[ThomasWaldmann]

Thanks @hexagonrecursion!

[rugk]

Great thing and great idea to automate that! BTW, are the (new) screencasts already live? As https://www.borgbackup.org/demo.html still shows the old ones…

[ThomasWaldmann]

@rugk https://github.com/borgbackup/borgbackup.github.io/tree/source/_assets there is the old stuff still.

guess one could have a look first at old vs. new and then, if all is ok, update the files there. PRs welcome.