Any easy way to install an older envoy version on macOS?

[Ofer Inbar]

"brew install envoy" only gives me the latest version. If I try any
@version it gives an error like "No formulae or casks found for en...@1.29.7"
And https://github.com/envoyproxy/envoy/releases doesn't have mac builds.

Is there any simple straightforward way to install an older version of
my choice, so that I can occasionally change to a different version
when I need to locally test configs using the same version that's in
use on the systems I'm testing for?
-- Cos

[Ofer Inbar]

Since I sent this yesterday, I ended up running docker containers with
local mount, like this:
docker run -it --rm --name envoy-validate -v .:/mnt envoy-local:1.29.7 --mode validate -c /mnt/envoy.yaml

I can start with a Dockerfile that just has "FROM envoyproxy/envoy:v1.29.7"
for whatever version I want, and don't have to rebuild the docker
image for each new config file edit, so that's good enough for now.

However, I'm still interested to know if I could easily install an
older version locally on my mac, and change versions occasionally,
without having to build each one from source or some other heavy
weight procedure.
-- Cos

[Jordi Miralles Comins]

Hello Ofer,

This is what I do for installing older versions:

- Version 1.27 (1.27.2)

curl https://raw.githubusercontent.com/Homebrew/homebrew-core/05994e9e8b043d8c8ff4e6d112f13bd1d213c449/Formula/e/envoy.rb -o envoy.rb
brew install envoy.rb

- Version 1.29 (1.29.3)

curl https://raw.githubusercontent.com/Homebrew/homebrew-core/a10bb0651833e92982e42ec036b7236f92963020/Formula/e/envoy.rb -o envoy.rb
brew install envoy.rb

- Version 1.30 (1.30.1)

curl https://raw.githubusercontent.com/Homebrew/homebrew-core/059e83331d75773467e79e6410d784576f5dfe72/Formula/e/envoy.rb -o envoy.rb
brew install envoy.rb

You hay to download the specific version from Homebrew formula repository for each version, using the commit hash. You can search versions here:
https://github.com/Homebrew/homebrew-core/commits/master/Formula/e/envoy.rb

You have to use the commit hash for the commits with name "envoy: update X.Y.Z bottle."

I hope this can help you,

Regards