chpg

Switch between installed Postgres.app versions.

$ chpg @11 && pg_dump --version
$ echo '11' > ./.chpg-version && chpg @ && pg_dump --version
$ chpg @latest && pg_dump --version
$ chpg help

Install

Open a terminal and run this command (view source):

(installs to $HOME/.local/bin; set PREFIX to override, e.g. PREFIX=/usr/local)

$ curl -L https://raw.githubusercontent.com/redding/chpg/main/install.sh | sh

Init

Add chpg init to your shell startup script. This installs tab completions and enables modifying the env vars.

eval "$(chpg init)"

Auto Mode

(optional) If you want automatic handling, add the --auto flag to the init. In addition to the normal init above, $PROMPT_COMMAND is updated to activate any new Postgres.app version as you change directories. Again, this is optional.

eval "$(chpg init --auto)"

Quiet Mode

By default, chpg outputs a warning saying which version/source it activates. If you want to silence these warnings, add the --quiet flag to the init.

eval "$(chpg init --quiet)"

Shims

chpg installs lightweight shims (in $HOME/.chpg/shims, added to your PATH by chpg init) for every executable across your installed Postgres.app versions. A shim resolves the correct version from the nearest .chpg-version at run time, so bare commands — psql, pg_dump, createdb, pg_config, … — use the right version in any shell, including non-interactive ones (scripts, cron, AI agents). No chpg @ prefix required.

Shims regenerate on install. Run chpg reshim after adding or removing a Postgres.app version. Use chpg which COMMAND to see the real path a command resolves to, and chpg resolve for the version that applies in the current directory.

Usage

$ chpg help

.chpg-version Files

If no explicit @ parameter is specified, chpg will look for the version in a file named .chpg-version in your current directory, its parent directories, or your home directory. The .chpg-version files are expected to contain nothing but the version requested.

$ echo "11" > $HOME/.chpg-version
$ cd $HOME && chpg @
$ pg_dump --version # will use /Applications/Postgres.app/Contents/Versions/11/bin/pg_dump

You can specify a specific version file using the -f option:

$ cd $HOME
$ echo "12" > /a/path/to/.chpg-version
$ chpg -f /a/path/to/.chpg-version
$ pg_dump --version # will use /Applications/Postgres.app/Contents/Versions/12/bin/pg_dump

Note: You can specify a "default" version file at $HOME/.chpg/.chpg-version. This version will be used when no other .chpg-version can be found and no command line version has been specified.

Note: If an @<version> parameter is given, it will always override any versions specified in any .chpg-version files.

Uninstall

Open a terminal and run this command (view source):

$ curl -L https://raw.githubusercontent.com/redding/chpg/main/uninstall.sh | sh

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Added some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create new Pull Request