Add support of subflow env var

packages/node_modules/@node-red/util/lib/util.js

@@ -413,6 +413,20 @@ function setObjectProperty(msg,prop,value,createMissing) {
     }
 }
 
+/**
+ * Get value of environment variable.
+ * @param {Node} node - accessing node
+ * @param {String} name - name of variable
+ * @return {String} value of env var
+ */
+function getenv(node, name) {
+    if (node && node.getenv) {
+        return node.getenv(name);
+    }
+    return process.env[name];
+}
+
+
 /**
  * Checks if a String contains any Environment Variable specifiers and returns
  * it with their values substituted in place.
@@ -420,24 +434,27 @@ function setObjectProperty(msg,prop,value,createMissing) {
  * For example, if the env var `WHO` is set to `Joe`, the string `Hello ${WHO}!`
  * will return `Hello Joe!`.
  * @param  {String} value - the string to parse
+ * @param  {Node} node - the node evaluating the property
  * @return {String} The parsed string
 * @memberof @node-red/util_util
  */
-function evaluateEnvProperty(value) {
+function evaluateEnvProperty(value, node) {
     if (/^\${[^}]+}$/.test(value)) {
         // ${ENV_VAR}
-        value = value.substring(2,value.length-1);
-        value = process.env.hasOwnProperty(value)?process.env[value]:""
+        var name = value.substring(2,value.length-1);
+        var val = getenv(node, name);
+        return val ? val : "";
     } else if (!/\${\S+}/.test(value)) {
         // ENV_VAR
-        value = process.env.hasOwnProperty(value)?process.env[value]:""
+        var val = getenv(node, value);
+        return val ? val : "";
     } else {
         // FOO${ENV_VAR}BAR
-        value = value.replace(/\${([^}]+)}/g, function(match, v) {
-            return process.env.hasOwnProperty(v)?process.env[v]:""
+        return value.replace(/\${([^}]+)}/g, function(match, name) {
+            var val = getenv(node, name);
+            return (val ? val : "");
         });
     }
-    return value;
 }
 
 
@@ -513,7 +530,7 @@ function evaluateNodeProperty(value, type, node, msg, callback) {
         var expr = prepareJSONataExpression(value,node);
         result = evaluateJSONataExpression(expr,msg);
     } else if (type === 'env') {
-        result = evaluateEnvProperty(value);
+        result = evaluateEnvProperty(value, node);
     }
     if (callback) {
         callback(null,result);
@@ -540,8 +557,9 @@ function prepareJSONataExpression(value,node) {
     expr.assign('globalContext',function(val) {
         return node.context().global.get(val);
     });
-    expr.assign('env', function(val) {
-        return process.env[val];
+    expr.assign('env', function(name) {
+        var val = getenv(node, name);
+        return (val ? val : "");
     })
     expr.registerFunction('clone', cloneMessage, '<(oa)-:o>');
     expr._legacyMode = /(^|[^a-zA-Z0-9_'"])msg([^a-zA-Z0-9_'"]|$)/.test(value);