Figure out a solution to state management

[bruno-garcia]

Currently the SDK has a single Hub hanging off of an AsyncLocal static field.

This doesn't work in some cases, like through round trip through native code calling into C#.

Also, in Desktop and Mobile apps, it's more common to expect state to be shared across the app.
This is how our Android and Cocoa SDKs work.
Currenly the Hub will fork and data set on a copied AsyncLocal won't propagate to the root one. That works well for Server apps, but not for desktop/mobile.

See: #221, #448

Relates to #628 (or just a dupe)

[bruno-garcia]

Dupe of: #628

[bruno-garcia]

We solved "Global Mode" on version 3.8.1.

It makes it so that any call to SentrySdk.SetTag or AddBreadcrumb or anything else that you do through SentrySdk.ConfigureScope mutates a single, static Scope object that affects all threads of the app. This is useful for Desktop and Mobile apps when you have a single user session and you add context to Sentry anywhere in the app and want that to be included if it crashes in any other thread.

You can opt-in to this mode through:

options.IsGlobalModeEnabled = true

To clarify: This options doesn't make sense in any sort of web server where each individual request takes a separate scope (You want each SetTag("url", ...) to take a different request URL, headers etc). Nothing needs to be done for server apps, it continues to work as it did in the past.

We plan to ship Sentry.Wpf and Sentry.WinForms in the future that would already flip IsGlobalModeEnabled = true for you. Until then we'll add to the docs that you can do that if you prefer to have a single mutable state.