From 2458e6c3d82eb1c3ad64132f4941293b6c690790 Mon Sep 17 00:00:00 2001
From: Maurus Decimus <11444311+mdecimus@users.noreply.github.com>
Date: Fri, 24 Apr 2026 14:32:52 +0200
Subject: [PATCH] Add `system(node_hostname)` and `system(node_role)`
 expression variables

---
 CHANGELOG.md                                 |  1 +
 crates/common/src/expr/eval.rs               | 10 ++++++++++
 crates/common/src/expr/functions/array.rs    |  4 ++--
 crates/common/src/expr/mod.rs                |  2 ++
 crates/common/src/expr/tokenizer.rs          |  2 ++
 crates/common/src/scripts/functions/array.rs |  4 ++--
 6 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0583e2ff..ca5353a1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ All notable changes to this project will be documented in this file. This projec
 This version includes **multiple breaking changes**. If you are upgrading from v0.15.x and below, please read the [upgrading documentation](https://github.com/stalwartlabs/stalwart/blob/main/UPGRADING/v0_16.md) for more information on how to upgrade from previous versions.
 
 ## Added
+- `system('node_hostname')` and `system('node_role')` expression variables to retrieve the local node hostname and cluster role respectively.
 
 ## Changed
 
diff --git a/crates/common/src/expr/eval.rs b/crates/common/src/expr/eval.rs
index 3d2b41d9..3fc27a8f 100644
--- a/crates/common/src/expr/eval.rs
+++ b/crates/common/src/expr/eval.rs
@@ -227,6 +227,16 @@ impl<'x, V: ResolveVariable> EvalContext<'x, V, Expression, &mut Vec<CompactStri
                         stack.push(self.core.core.email.default_domain_name.as_str().into())
                     }
                     SystemVariable::NodeId => stack.push(self.core.core.network.node_id.into()),
+                    SystemVariable::NodeHostname => {
+                        stack.push(self.core.registry().local_hostname().into())
+                    }
+                    SystemVariable::NodeRole => stack.push(
+                        self.core
+                            .registry()
+                            .cluster_role()
+                            .unwrap_or_default()
+                            .into(),
+                    ),
                     SystemVariable::Metric(variable) => {
                         stack.push(Variable::Float(Collector::read_metric(*variable)));
                     }
diff --git a/crates/common/src/expr/functions/array.rs b/crates/common/src/expr/functions/array.rs
index 31b08a14..69f10e28 100644
--- a/crates/common/src/expr/functions/array.rs
+++ b/crates/common/src/expr/functions/array.rs
@@ -24,9 +24,9 @@ pub(crate) fn fn_sort(mut v: Vec<Variable>) -> Variable {
     let is_asc = v[1].to_bool();
     let mut arr = v.remove(0).into_array();
     if is_asc {
-        arr.sort_unstable_by(|a, b| b.cmp(a));
-    } else {
         arr.sort_unstable();
+    } else {
+        arr.sort_unstable_by(|a, b| b.cmp(a));
     }
     arr.into()
 }
diff --git a/crates/common/src/expr/mod.rs b/crates/common/src/expr/mod.rs
index aa6b2a04..d07c1490 100644
--- a/crates/common/src/expr/mod.rs
+++ b/crates/common/src/expr/mod.rs
@@ -175,6 +175,8 @@ pub enum SystemVariable {
     Hostname,
     Domain,
     NodeId,
+    NodeHostname,
+    NodeRole,
     Metric(MetricType),
 }
 
diff --git a/crates/common/src/expr/tokenizer.rs b/crates/common/src/expr/tokenizer.rs
index 125cb807..01a8c863 100644
--- a/crates/common/src/expr/tokenizer.rs
+++ b/crates/common/src/expr/tokenizer.rs
@@ -119,6 +119,8 @@ impl<'x> Tokenizer<'x> {
                                     "domain" => SystemVariable::Domain,
                                     "hostname" => SystemVariable::Hostname,
                                     "node_id" => SystemVariable::NodeId,
+                                    "node_hostname" => SystemVariable::NodeHostname,
+                                    "node_role" => SystemVariable::NodeRole,
                                     other => {
                                         return Err(format!(
                                             "Invalid system variable name {:?}",
diff --git a/crates/common/src/scripts/functions/array.rs b/crates/common/src/scripts/functions/array.rs
index 9d6be10c..6d537e49 100644
--- a/crates/common/src/scripts/functions/array.rs
+++ b/crates/common/src/scripts/functions/array.rs
@@ -26,9 +26,9 @@ pub fn fn_sort<'x>(_: &'x Context<'x>, v: Vec<Variable>) -> Variable {
     let is_asc = v[1].to_bool();
     let mut arr = (*v[0].to_array()).clone();
     if is_asc {
-        arr.sort_unstable_by(|a, b| b.cmp(a));
-    } else {
         arr.sort_unstable();
+    } else {
+        arr.sort_unstable_by(|a, b| b.cmp(a));
     }
     arr.into()
 }