GOOGLE_CHROME_SHIM now responds to --version and --product-version.

[kapoorlakshya]

This change adds out-of-the-box compatibility with the webdrivers gem, which apparently quite a few Heroku users are using. Currently, the users have to use a workaround in their project to get the Chrome version from $GOOGLE_CHROME_BIN, so that webdrivers can download the appropriate version of chromedriver, and then switch back to $GOOGLE_CHROME_SHIM to launch Chrome.

See titusfortner/webdrivers#40, titusfortner/webdrivers#72, and titusfortner/webdrivers#134.

This simple change will provide the convenience of not needing any hacks to make the two work :).

[twalpole]

@kapoorlakshya That's great - hopefully it's accepted -- I do wonder why chrome on linux has --product-version and --version while on MacOS there's only --version. Since on linux chrome does accept both --version and --product-version (one is just the number the other has extra text) It might be nice to have the shim do the right thing with either of them.

[kapoorlakshya]

It might be nice to have the shim do the right thing with either of them.

I agree. I'll go ahead and add another condition to have it respond to --version as well.

[kapoorlakshya]

$ google-chrome-stable --version
Google Chrome 74.0.3729.108

$ google-chrome-stable --product-version
74.0.3729.108

[kapoorlakshya]

Hi @joshwlewis and @jabrown85, is there any chance of this getting reviewed/merged?

[richardvenneman]

Can confirm this fix works great in production, thanks 🙏

[jabrown85]

I deployed this to the buildpack registry and it's in master for those not using the shorthand buildpack name heroku/google-chrome. Thanks for the contribution!

[kapoorlakshya]

@jabrown85 Thank you very much!

[isc]

Shouldn't the $ in $1 be escaped ?
When using the heroku/google-chrome buildpack and running heroku ci:debug, I get

~ $ cat $GOOGLE_CHROME_SHIM   
#!/usr/bin/env bash
if [ /app = "--version" ]; then
  exec $HOME/.apt/opt/google/chrome/chrome --version
elif [ /app = "--product-version" ]; then
  exec $HOME/.apt/opt/google/chrome/chrome --product-version
else
  exec $HOME/.apt/opt/google/chrome/chrome --headless --no-sandbox --disable-gpu --remote-debugging-port=9222 $@
fi
~ $ 

[kwlockwo]

Yes this is correct, I'm seeing this:

if [ /tmp/build_9b8b699572a1f61d9096ed0e275f2c41 = "--version" ]; then

because the $1 isn't escaped.

[kwlockwo]

Fixed in #74

[kapoorlakshya]

Thanks for fixing it, but just curious why you would call cat on the shim. I thought the shim was solely used to launch Chrome with the extra args, like headless.

Sorry, not a Heroku user.

[isc]

@kapoorlakshya I called cat on the shim while debugging to confirm that I still needed the workaround despite what this PR said.

[kapoorlakshya]

@isc Can you please share what's not working? I would appreciate a bug report on the webdrivers repo when you have a chance.

[kwlockwo]

@kapoorlakshya it is fixed in #74

@isc was just doing the cat to illustrate the problem. Which was that $1 was being substituted during the build which from memory is the root directory where your app is built (often set as ${BUILD_DIR} in buildpacks).

This has been merged to master and pushed to our buildpack registry.

[kapoorlakshya]

@kwlockwo Right. I was addressing his comment which sounded like the workaround for webdrivers is still required, but perhaps I misunderstood.

Anyway, thanks again for #74.