SE-0378: Swift Package Registry Authentication

The review of SE-0378: Swift Package Registry Authentication, begins now and runs through Dec 2nd, 2022.

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To avoid accidental removal of sensitive data, .netrc file needs to be updated manually by the user.

Will there be a prompt at logout time to remind the user of this fact?

Yes, it will output something like this:

netrc file not updated. Please remove credentials from the file manually.
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  1. SwiftPM will perform lookups in one credential store only. For macOS, it will be Keychain. For all other platforms, it will be the user-level .netrc file.

Would it be possible to retain support for netrc file as a credential source on all platforms? For automation environment (CI etc), it is much easier to manage, and it is used by several other tools (curl including).

Example from another tool is NuGet - it uses secure store to encrypt passwords on Windows, but it supports clear text passwords on all platforms as well.

Yes, given there's no official workflow from Apple for deploying keychains as part of a build system, how exactly does Apple expect this to work? Even when we make them manually work through the security command or Fastlane wrapper, they're very fragile and hard to debug, making them a rather poor solution even at the best of times. There needs to be a pragmatic approach here.


Could you please elaborate on how the security command is fragile?

Perhaps it's not the command itself but the results of it interacting with a keychain that are fragile. Most notably, in environments that aren't entirely blown away, like dedicated builders, there seems to be some sort of keychain caching. Updated keychain files with the same file name aren't actually opened in a way that makes their updated contents properly available. I've had to make various hacks where the keychain is copied to a file with a random name and then opened for the updated items to be properly visible.

There are also other keychain issues with the security command, like no proper separation between add / delete and lock / unlock, as well as issues around the interaction with Keychain Access where keychains which have be installed and then deleted are still visible in the UI.

A third issue is that some CI systems, like GitHub Actions, don't support proper secure file injection. Instead, the keychain is base64 encoded as a secret string and then decoded to disk and opened in the builder. Being able to provide environment values directly would be much nicer.


True, being able to use environment variables seems like a good compromise to me.

Env vars are good, but how it would be implemented in this case (per server basis)?

Time is running out, are there any ideas how to deal with this? Thanks

Would it be possible to retain support for netrc file as a credential source on all platforms?

@mdvorak This is what you are asking for primarily, correct?

@yim_lee To be precise, problematic is SwiftPM will perform lookups in one credential store only, but yeah, thats about it.
If I remember that correctly, desired behavior (with fallback) is a current implementation, and this change removes it.

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@mdvorak Got it. We will likely have some way for users to override the default so they can use netrc if they choose.

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SE-0378 has been accepted with modification. If you'd like to continue discussing this, please do so in that thread.