1 files changed, 50 insertions, 0 deletions
diff --git a/version/updates/updates.go b/version/updates/updates.go
new file mode 100644
index 000000000..df39e6bd9
--- /dev/null
+++ b/version/updates/updates.go
@@ -0,0 +1,50 @@
+// Copyright (c) 2021 Tailscale Inc & AUTHORS All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Packate updates is an evalator for a update policy file that controls
+// when users get update available notifications (and which types).
+//
+// It's used and hot reloaded by several servers. It permits us to
+// centralize and test the update policy.
+package updates
+
+type Policy struct {
+	Tests []*Test
+	Rules []*Rule
+}
+
+type Test struct {
+	OS     string
+	Distro string // "synology" on Linux
+	Ver    string // "1.2.3-tXXXX-gXXX"
+	Want   string // "", "update", "update/security"
+}
+
+type Rule struct {
+	// Ver, if non-empty, matches the version number.
+	// If it begins with an operator ("<", "<=", then the comparison
+	// is done semantically based on semver, not lexically.
+	Ver string
+
+	// OS, if non-empty, matches the node operating system.
+	// Possible values: "linux", "windows", "macOS", "iOS", or
+	// else a runtime.GOOS value (except not "darwin" or "ios").
+	OS string
+
+	// Package, if non-empty, matches the packaging variant.
+	// Possible values: "choco", "appstore", "macsys", "tailscaled".
+	Package string
+
+	// Distro, if non-empty, matches the node's distro.
+	// Possible values: "synology".
+	Distro string
+
+	// Now, if non-empty, matches based on the current date in UTC.
+	// e.g. ">=2021-10-07".
+	Now string
+
+	Then      string // "stop", "update", "update/security", "update: note"
+	ThenRules []*Rule
+	ElseRules []*Rule
+}