Create optional lock file for use of the data-store by external process

[cblauvelt]

I would like the option to create a lock file when the data-store is being synchronized. I understand this can cause slow-down so it would be off by default.

[cblauvelt]

I am willing to provide a patch but wanted to know if you would be open to accepting it and if adding lockfile from https://github.com/npm/lockfile would be acceptable to implement.

[jonschlinkert]

You can use lockfiles in your own libraries to lock the version of data-store to whatever you want. However, for reasons that will take more time to explain than I have right now, we don't use lockfiles in our libraries. Lockfiles prevent semver from doing it's job, and our experience has been that - between semver and lockfiles - semver is the lesser of two evils.

[doowb]

@jonschlinkert I don't think @cblauvelt was talking about a package lock file, but a lockfile to only allow a single process to access the file at a time.

[cblauvelt]

@doowb I was a little confused bye the response and I was trying to figure out how semver would prevent another process from accessing the file while it was being written. @jonschlinkert I am trying to prevent an external process from reading the data-store while the file is being written and I am not trying to implement a package lock file such as that used by npm or yarn.

[jonschlinkert]

Oh like a mutex?

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On Sep 13, 2019, at 3:59 PM, Brian Woodward ***@***.***> wrote: @jonschlinkert I don't think @cblauvelt was talking about a package lock file, but a lockfile to only allow a single process to access the file at a time. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[jonschlinkert]

Got it. Yeah I think you’re looking for atomic writes. Or we can use a mutex, or a combination of those.

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Sent from my iPhone

On Sep 13, 2019, at 4:04 PM, cblauvelt ***@***.***> wrote: @doowb I was a little confused bye the response and I was trying to figure out how semver would prevent another process from accessing the file while it was being written. @jonschlinkert I am trying to prevent an external process from reading the data-store while the file is being written and I am not trying to implement a package lock file such as that used by npm or yarn. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.

[cblauvelt]

Exactly like a mutex.