Patches not applied when using Heroku's Node buildpack

[Oliver Joseph Ash]

This isn't an issue with patch-package specifically, but I wanted to share it here nonetheless to help anyone else who might run into this.

When using Heroku's Node buildpack, by default the following will happen during the build and startup process:

1. install all dependencies (including devDependencies) with yarn --production="false"
2. run build step
3. prune dev dependencies with yarn --production="true"
4. run the app

However, at step 3 when the dev dependencies are pruned, the buildpack also specifies the --ignore-scripts flag when calling yarn (since v119). This means patch-package will not run, because the postinstall/prepare scripts will not be ran. In turn, this means when the app runs, Node modules will not be patched (!).

The only workaround I'm aware of at the moment is to disable pruning of dev dependencies with YARN_PRODUCTION=false.

I can semi-understand why the buildpack would want to avoid invoking scripts, since the scripts were already run after step 1. In any case I've raised an issue with the buildpack to investigate what changes we can make there: heroku/heroku-buildpack-nodejs#634

[Oliver Joseph Ash]

Immediately closing this as it's not a bug with patch-package, but hopefully this will be helpful to others. @ds300 If you have ideas for alternative workarounds or fixes, I'd love to hear them!

[Oliver Joseph Ash]

I just ran into this again when setting up patch-package on a fresh Heroku application. Perhaps we should add a note to the docs for Heroku users: #209

[Nate]

Looks like with the latest version of the Heroku nodejs build script, you can accomplish this by using the heroku-postbuild step. That allows patch-package to work without losing the dev dependency pruning 🎉 .

Here's what my package.json scripts look like now:

  "scripts": {
    "postinstall": "patch-package",
    "heroku-postbuild": "patch-package"
  }

[Neo Kim]

heroku-postbuild didn't work for me. Looks like during pruning dev dependencies which runs after heroku-postbuild, yarn restores the original version of packages. So I had to use heroku-cleanup instead which runs after pruning.

Actually, Heroku document says it runs after dependency caching, but it works for me anyway.

[Esteban]

@neokim suggestion to use heroku-cleanup instead of heroku-postbuild worked for us. 🤝

[Alexander]

I added "heroku-cleanup": "npx patch-package" to my package.json for Strapi app
and output shows

remote: -----> Cleanup
remote:        Running heroku-cleanup
remote:        
remote:        > my-project@0.1.0 heroku-cleanup
remote:        > npx patch-package
remote:        
remote:        patch-package 6.4.7
remote:        Applying patches...
remote:        @strapi/admin@4.1.12 ✔

But no changes applyed. What am I doing wrong?

[Previesam]

@AlexanderPershin It worked for me I am also using strapi.

So i added "postinstall": "npx patch-package", "heroku-postbuild": "npx patch-package", "heroku-cleanup": "npx patch-package" but looking at the logs only heroku cleanup should do the trick.

[ChrisChiasson]

Warning: If you add heroku-postbuild, your build script will NOT execute: https://devcenter.heroku.com/articles/nodejs-support#customizing-the-build-process

[Paul Bratslavsky]

Has anyone had this issue on digital ocean?

[Frikha Ahmad]

@Previesam @AlexanderPershin For strapi staging, I added:
"postinstall": "npx patch-package",
For prod, I also added:
"heroku-cleanup": "npx patch-package"

[Benjie]

The solution is to add the heroku-cleanup (different from heroku-postbuild) script to your "scripts" in package.json; the reason being that the Heroku cleanup clears out the devDependencies, which triggers another call to your package manager, ignoring scripts, and thus patch-package is not called again. This causes issues for yarn at least.

{
  // ...
  "scripts": {
    "heroku-cleanup": "npx patch-package",
    // ...

Thanks to @IceBreaker8 above for the solve.