CAMEL-5960 Add routeId as function to simple language

camel-core/src/main/java/org/apache/camel/builder/ExpressionBuilder.java

@@ -1394,6 +1394,22 @@ public String toString() {
         };
     }
 
+    /**
+     * Returns an Expression for the route id
+     */
+    public static Expression routeIdExpression() {
+        return new ExpressionAdapter() {
+            public Object evaluate(Exchange exchange) {
+                return exchange.getFromRouteId();
+            }
+
+            @Override
+            public String toString() {
+                return "routeId";
+            }
+        };
+    }
+
     public static Expression dateExpression(final String command, final String pattern) {
         return new ExpressionAdapter() {
             public Object evaluate(Exchange exchange) {

camel-core/src/main/java/org/apache/camel/language/simple/ast/SimpleFunctionExpression.java

@@ -315,6 +315,8 @@ private Expression createSimpleExpressionDirectly(String expression) {
             return ExpressionBuilder.threadNameExpression();
         } else if (ObjectHelper.equal(expression, "camelId")) {
             return ExpressionBuilder.camelContextNameExpression();
+        } else if (ObjectHelper.equal(expression, "routeId")) {
+            return ExpressionBuilder.routeIdExpression();
         }
 
         return null;

camel-core/src/test/java/org/apache/camel/language/simple/SimpleTest.java

@@ -124,6 +124,9 @@ public void testSimpleExpressions() throws Exception {
         assertExpression("in.headers.foo", "abc");
         assertExpression("header.foo", "abc");
         assertExpression("headers.foo", "abc");
+        assertExpression("routeId", exchange.getFromRouteId());
+        exchange.setFromRouteId("myRouteId");
+        assertExpression("routeId", "myRouteId");
     }
 
     public void testTrimSimpleExpressions() throws Exception {