feat: Add support for update checks and notifications (#4810)

Co-authored-by: Kira Pilot <kira@coder.com>

cli/deployment/config.go

@@ -14,6 +14,7 @@ import (
 	"github.com/spf13/viper"
 	"golang.org/x/xerrors"
 
+	"github.com/coder/coder/buildinfo"
 	"github.com/coder/coder/cli/cliui"
 	"github.com/coder/coder/cli/config"
 	"github.com/coder/coder/codersdk"
@@ -405,6 +406,12 @@ func newConfig() *codersdk.DeploymentConfig {
 			Usage: "Enable experimental features. Experimental features are not ready for production.",
 			Flag:  "experimental",
 		},
+		UpdateCheck: &codersdk.DeploymentConfigField[bool]{
+			Name:    "Update Check",
+			Usage:   "Periodically check for new releases of Coder and inform the owner. The check is performed once per day.",
+			Flag:    "update-check",
+			Default: flag.Lookup("test.v") == nil && !buildinfo.IsDev(),
+		},
 	}
 }
 

cli/deployment/config_test.go

@@ -38,6 +38,7 @@ func TestConfig(t *testing.T) {
 			"CODER_TELEMETRY":            "false",
 			"CODER_TELEMETRY_TRACE":      "false",
 			"CODER_WILDCARD_ACCESS_URL":  "something-wildcard.com",
+			"CODER_UPDATE_CHECK":         "false",
 		},
 		Valid: func(config *codersdk.DeploymentConfig) {
 			require.Equal(t, config.Address.Value, "0.0.0.0:8443")
@@ -53,6 +54,7 @@ func TestConfig(t *testing.T) {
 			require.Equal(t, config.Telemetry.Enable.Value, false)
 			require.Equal(t, config.Telemetry.Trace.Value, false)
 			require.Equal(t, config.WildcardAccessURL.Value, "something-wildcard.com")
+			require.Equal(t, config.UpdateCheck.Value, false)
 		},
 	}, {
 		Name: "DERP",

cli/server.go

@@ -63,6 +63,7 @@ import (
 	"github.com/coder/coder/coderd/prometheusmetrics"
 	"github.com/coder/coder/coderd/telemetry"
 	"github.com/coder/coder/coderd/tracing"
+	"github.com/coder/coder/coderd/updatecheck"
 	"github.com/coder/coder/codersdk"
 	"github.com/coder/coder/cryptorand"
 	"github.com/coder/coder/provisioner/echo"
@@ -373,6 +374,25 @@ func Server(vip *viper.Viper, newAPI func(context.Context, *coderd.Options) (*co
 				options.TLSCertificates = tlsConfig.Certificates
 			}
 
+			if cfg.UpdateCheck.Value {
+				options.UpdateCheckOptions = &updatecheck.Options{
+					// Avoid spamming GitHub API checking for updates.
+					Interval: 24 * time.Hour,
+					// Inform server admins of new versions.
+					Notify: func(r updatecheck.Result) {
+						if semver.Compare(r.Version, buildinfo.Version()) > 0 {
+							options.Logger.Info(
+								context.Background(),
+								"new version of coder available",
+								slog.F("new_version", r.Version),
+								slog.F("url", r.URL),
+								slog.F("upgrade_instructions", "https://coder.com/docs/coder-oss/latest/admin/upgrade"),
+							)
+						}
+					},
+				}
+			}
+
 			if cfg.OAuth2.Github.ClientSecret.Value != "" {
 				options.GithubOAuth2Config, err = configureGithubOAuth2(accessURLParsed,
 					cfg.OAuth2.Github.ClientID.Value,

cli/testdata/coder_server_--help.golden

@@ -219,6 +219,10 @@ Flags:
                                                      verbose flag was supplied, debug-level
                                                      logs will be included.
                                                      Consumes $CODER_TRACE_CAPTURE_LOGS
+      --update-check                                 Periodically check for new releases of
+                                                     Coder and inform the owner. The check is
+                                                     performed once per day.
+                                                     Consumes $CODER_UPDATE_CHECK
       --wildcard-access-url string                   Specifies the wildcard hostname to use
                                                      for workspace applications in the form
                                                      "*.example.com".