infra: add documentation on how to use sentry

Author: pietroalbini

src/SUMMARY.md

@@ -61,6 +61,7 @@
         - [Monitoring](./infra/docs/monitoring.md)
         - [rust-bots server](./infra/docs/rust-bots.md)
         - [rust-lang/rust CI](./infra/docs/rustc-ci.md)
+        - [Sentry](./infra/docs/sentry.md)
 - [Language](./lang/README.md)
     - [RFC Merge Procedure](./lang/rfc-merge-procedure.md)
     - [Triage Meeting Procedure](./lang/triage-meeting-procedure.md)

src/infra/docs/sentry.md

@@ -0,0 +1,49 @@
+# Sentry
+
+The infrastructure team manages a [Sentry](https://sentry.io) organization on
+`sentry.io` for the Rust Team to use. The instance is generously sponsored by
+Sentry, and this document explains how to use it.
+
+## Log into the instance
+
+Every member of the `rust-lang` GitHub organization can authenticate in our
+Sentry instance, using their GitHub credentials. Visit [the authentication
+page][auth], click the "Single Sign-On" tab and enter the `rust-lang`
+Organization ID. You'll be then prompted to log with your GitHub Account!
+
+If this is the first time signing into our Sentry organization, you might have
+to [request access to the teams you're on][teams]. Once you request access, a
+member of the infrastructure team will approve it.
+
+## Request a new project
+
+If you're a member of a Rust Team and you want to use Sentry for a project your
+team manages, you need to follow these steps:
+
+1. If the project is public facing (i.e. people outside the team are supposed
+   to access it) you need to contact [Rust's legal counsel][legal] to amend the
+   privacy policy, adding a note that your service is using Sentry too similar
+   to the existing ones.
+
+2. Once the privacy policy is sorted out (whenever needed), you can contact the
+   infrastructure team to create a new project in the Sentry interface and
+   potentially a new Sentry team.
+
+3. Finally, you can integrate the Sentry SDK with your project.
+
+## Creating a new project
+
+This section documents how the infrastructure team can actually create new
+projects when requested. You need to either have a personal Sentry account with
+"Owner" permissions, or access to the Sensitive 1Password vault (where the
+admin credentials are stored).
+
+To create a project, authenticate in Sentry and visit the [create new project
+page][create]. Pick the technology stack the team is using, a relevant name and
+the team responsible for it (you can create new teams by clicking the "+"
+icon). Finally, if you created a new team, add the relevant people to it.
+
+[auth]: https://sentry.io/auth/login/
+[teams]: https://sentry.io/settings/rust-lang/teams/
+[legal]: /core/legal.md
+[create]: https://sentry.io/organizations/rust-lang/projects/new/