My shell prompt is hideous and grotesque, with warts from compatibility hacks for ancient versions of zsh. Every time I think "I can drop that hack" I end up cloning my ~/.personal repo onto a box with an even more ancient version of zsh and crying a little inside, before restoring compatibility hacks.

Nonetheless, various friends and former co-workers have asked for my prompt setup. So I threw together this repo to hold a few zsh functions which are potentially useful to others.

With the above in mind, complaints about the grotesqueness of the code will be filed in the circular filing cabinet on the floor. Bug-fixes without snark gratefully received.

Note that zstyle is needed to turn some prompt features on or off, or invoking with options to toggle features.

Licensed per LICENSE.txt.
Note: the first copyright year is my best guess of when this version of the shell prompt started growing. It might be a year or two off. I don't want to have to resurrect svn or ask around for old CVS repos to be sure. If this is ever seriously an issue, I'll cry a little more.

In ~/.zshrc or equivalent:

# zstyle ':prompt:pdp*:*' use-cache on
autoload promptinit
promptinit
prompt pdp

setopt transient_rprompt

I actually have setup to maintain a per-host cache in an OS-specific cache location, so that ~/Library/Caches/zsh/osmium is correct for my current laptop; this then feeds into uncommenting the use-cache above.

My macOS laptop had:

zstyle ':prompt:pdp*:*' employer-domain pennock-tech.net
zstyle ':prompt:pdp*:*' employer-prompt $'@%{\e[38;2;0;180;222m%}PennockTech%{\e[0m%}'
zstyle ':prompt:pdp*:*' show-domain off
zstyle ':prompt:pdp*:*' auto-kerberos on
zstyle ':prompt:pdp*:*' show-awscreds on

My Linux laptop, unable to use the aws-vault info sub-command to get rotation times, skips show-awscreds but does have:

zstyle ':prompt:pdp*:*' show-awsprofile on
zstyle ':prompt:pdp*:*' show-pyenv on

Another box just has:

zstyle ':prompt:pdp*:*' show-sshkeys on
zstyle ':prompt:pdp*:*' show-gpgagent on

There is now support for displaying the current pyenv version-name in the right-hand-side prompt RPS1; it also supports being auto-enabled via setting an environment variable, to integrate with direnv(1). To use it, wherever you export PYENV_VERSION=... also export _prompt_pdp_pyenv='!' as a trigger. The prompt functions will spot that the internal variable is exported and unexport it, before turning on its own pyenv mode. This support doesn't handle arbitrary "something assigned to PYENV_VERSION, unfortunately. We'd need watches on variables for that.

I now display by default a rendering of $KUBE_CONTEXT and $KUBE_NAMESPACE in my RHS prompt, used by my wrappers around kubectl and helm so that I can change into a directory with a .envrc containing something like export KUBE_NAMESPACE=top-www and be automatically pointed to the right bit of a Kubernetes cluster for a given app.

When setting authentication credentials or the like into variables, it's handy to be able to tell apart the tabs and know which variables are available to me. Arbitrary content can be assigned to PDP_LABEL (non-exported) just to get a convenient red tag.

With this expansion in the use of $RPS1, setting the zsh transient_rprompt option makes it much easier to copy/paste commands without the RHS prompt getting in the way.

Set up autoload for these and most of them will help with tab-completion.

• _aws — wrapper around bash completion, this one actually works
• _aws_profiles — let AWS_PROFILE= tab-complete usefully
• _aws-vault — completion for aws-vault
• _docker_contexts — let DOCKER_CONTEXT= tab-complete usefully
• _pyenv_versions — let PYENV_VERSION= tab-complete usefully
• _ssh-kube-gcloud — completion for bin/ssh-kube-gcloud which is a wrapper around gcloud compute ssh; gcloud's tab-completion hits a remote end-point every time you press tab, so is hideously slow. This completion caches, making it occasionally slow but usually fast.
• _vagrant — decent fast tab-completion for Vagrant
• _kube_contexts & _kube_namespaces — completion for KUBE_CONTEXT= & KUBE_NAMESPACE=
• _nodenv_versions, _pyenv_versions, _rbenv_versions — completion for shell variables for controlling the respective interpreter dispatchers.
• prompt_pdp_setup — invoked by zsh's prompt framework when told to use the pdp prompt
• kerb_remaining_time — cached invocation of klist(1) to determine remaining kerberos ticket lifetime, for prompt display
• iterm_tabcolor_rgb — setting tab colors for iTerm without another fork/exec

I also use some items in zfuncs.zsh which are not auto-loaded but are directly in-line, typically to avoid defining them unless some command is installed.

I use https://github.com/nnao45/zsh-kubectl-completion for completing kubectl. This is compatible with compdef aliasing so that I can have k tab-complete too (either add k=kubectl to the #compdef line at the start of the file, or run compdef _kubectl k=kubectl after loading).