Add middleware for using system ctx in middlewares

Emyrk · Emyrk · commit bebe6384d7fc · 2023-02-10T11:28:18.000-06:00
diff --git a/coderd/coderd.go b/coderd/coderd.go
@@ -295,8 +295,11 @@ func New(options *Options) *API {
 				DisableSessionExpiryRefresh: options.DeploymentConfig.DisableSessionExpiryRefresh.Value,
 				Optional:                    true,
 			}),
-			httpmw.ExtractUserParam(api.Database, false),
-			httpmw.ExtractWorkspaceAndAgentParam(api.Database),
+			// TODO: We should remove this auth context after middleware.
+			httpmw.AsAuthzSystem(
+				httpmw.ExtractUserParam(api.Database, false),
+				httpmw.ExtractWorkspaceAndAgentParam(api.Database),
+			),
 		),
 		// Build-Version is helpful for debugging.
 		func(next http.Handler) http.Handler {
@@ -323,6 +326,8 @@ func New(options *Options) *API {
 				DisableSessionExpiryRefresh: options.DeploymentConfig.DisableSessionExpiryRefresh.Value,
 				Optional:                    true,
 			}),
+			// TODO: We should remove this auth context after middleware.
+			httpmw.SystemAuthCtx,
 			// Redirect to the login page if the user tries to open an app with
 			// "me" as the username and they are not logged in.
 			httpmw.ExtractUserParam(api.Database, true),
diff --git a/coderd/httpmw/authz.go b/coderd/httpmw/authz.go
@@ -0,0 +1,30 @@
+package httpmw
+
+import (
+	"net/http"
+
+	"github.com/coder/coder/coderd/database/dbauthz"
+
+	"github.com/go-chi/chi/v5"
+)
+
+// AsAuthzSystem is a bit of a kludge for now. Some middleware functions require
+// usage as a system user in some cases, but not all cases. To avoid large
+// refactors, we use this middleware to temporarily set the context to a system.
+//
+// TODO: Refact the middleware functions to not require this.
+func AsAuthzSystem(mws ...func(http.Handler) http.Handler) func(http.Handler) http.Handler {
+	chain := chi.Chain(mws...)
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+			ctx := r.Context()
+			before, _ := dbauthz.ActorFromContext(r.Context())
+
+			r = r.WithContext(dbauthz.AsSystem(ctx))
+			chain.Handler(http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+				r = r.WithContext(dbauthz.As(r.Context(), before))
+				next.ServeHTTP(rw, r)
+			})).ServeHTTP(rw, r)
+		})
+	}
+}
