You're right, it's racy. I'll update the sample.
file.DefaultBucketName will indeed return the same result every time (unless the default bucket is updated in the App Engine admin console). On Tue, Nov 8, 2016 at 12:40 PM, Greg Jones <greg.jo...@gmail.com> wrote: > You're not wrong, that code isn't a safe use of a package-level variable. > > On Tuesday, 8 November 2016 20:16:28 UTC, krolaw wrote: >> >> Hopefully someone can explain where my understanding of dataraces is >> wrong. >> >> As an example, I'd like to use the appengine cloudstorage example: >> https://cloud.google.com/appengine/docs/go/googlecloudstorag >> eclient/app-engine-cloud-storage-sample#specifying_the_cloud >> _storage_bucket >> >> When a web request comes in, it checks if the bucketname is empty. If it >> is, it sets the bucketname using the result from >> file.DefaultBucketName(ctx). It all seems like a good idea, but I'm >> confused because the bucket name variable is accessed by multiple >> goroutines. What if on startup, two requests come in at roughly the same >> time? Would we possibly have two goroutines reading and writing to the >> same variable? Does the appengine guarantee that the first request >> finishes before any other starts? Or is this somehow a minor unimportant >> datarace, as it is unlikely to occur and even if it does, >> file.DefaultBucketName returns the same value... so it doesn't matter that >> it gets called twice and sets the bucket name twice? >> >> Thanks and apologies for my confusion. >> >> -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
