Possible regression in yarn, can't deploy

[groeneman]

Related to yarnpkg/yarn#1818

Looks like there's a regression in yarn 0.17.0 that is breaking Heroku deploys. From looking at

heroku-buildpack-nodejs/lib/binaries.sh

Line 14 in a40755c

local download_url="https://yarnpkg.com/latest.tar.gz"

it appears that the buildpack always installs the latest version of yarn. I'm not seeing a way to download a specific version of yarn from https://yarnpkg.com/, but seems like that's what we'd need to do until the regression is fixed.

remote: -----> Installing binaries
remote:        engines.node (package.json):  unspecified
remote:        engines.npm (package.json):   unspecified (use default)
remote:        
remote:        Resolving node version (latest stable) via semver.io...
remote:        Downloading and installing node 5.11.1...
remote:        Using default npm version: 3.8.6
remote:        Downloading and installing yarn...
remote: /tmp/build_b05305c5f30e428e6609342e840711f1/.heroku/yarn/bin/yarn.js:47
remote:       throw err;
remote:       ^
remote: 
remote: Error: ENOENT: no such file or directory, open '/app/.cache/yarn/.roadrunner.json'
remote:     at Error (native)
remote:     at Object.fs.openSync (fs.js:584:18)
remote:     at Object.fs.writeFileSync (fs.js:1224:33)
remote:     at /tmp/build_b05305c5f30e428e6609342e840711f1/.heroku/yarn/node_modules/roadrunner/index.js:25:6
remote:     at /tmp/build_b05305c5f30e428e6609342e840711f1/.heroku/yarn/node_modules/roadrunner/index.js:12:12
remote:     at emitOne (events.js:95:20)
remote:     at process.emit (events.js:182:7)
remote:     at processEmit [as emit] (/tmp/build_b05305c5f30e428e6609342e840711f1/.heroku/yarn/node_modules/signal-exit/index.js:140:35)
remote:     at process.exit (internal/process.js:79:15)
remote:     at Command.<anonymous> (/tmp/build_b05305c5f30e428e6609342e840711f1/.heroku/yarn/node_modules/commander/index.js:825:13)
remote:        Installed yarn 0.17.0

[dpatti]

Here's a forked buildpack that installs 0.16.1 if anyone needs a quick workaround:

https://github.com/Genius/heroku-buildpack-nodejs.git#yarn-0.16.1

And here's the commit if you'd rather do it yourself: Genius@37a4c33

[hunterloftis]

Thanks for the heads up, I'll implement yarn versioning this week. Thanks @dpatti for the workaround.

[Daniel15]

I'm not seeing a way to download a specific version of yarn from https://yarnpkg.com/

You can use https://yarnpkg.com/downloads/0.16.1/yarn-v0.16.1.tar.gz as the download URL if you'd like to lock it to a particular Yarn version

[kevinzwhuang]

@hunterloftis any update on yarn versioning with the buildpack?

[joshmanders]

Not to be annoying, but curious what's the status of this? Do you need assistance getting it shipped? RIght now I use yarn for everything everywhere, locally, in CI, and buildpacks are the only place it's missing.

[hunterloftis]

All set in master. You can:

1. Just check yarn.lock into git, to pull the latest version
2. Optionally set engines.yarn in package.json (to either a version or a semver range)