Create select_named_headers_from_sourceMap.js

select_named_headers_from_sourceMap.js

@@ -0,0 +1,41 @@
+/**
+ * Creates a LinkedHashMap from provided headers and header keys.
+ * This function is based on original work by Tony Germano (@agermano) from Mirth Slack.
+ *
+ * @param {Object} headers - The headers object containing header lists.
+ * @param {Array} headerKeys - An array of header keys to be included in the map.
+ * @param {boolean} excludeNullValues - Flag to determine whether to exclude null values.
+ * @returns {java.util.LinkedHashMap} - A LinkedHashMap with header keys and their corresponding last values.
+ */
+function createHeaderMap(headers, headerKeys, excludeNullValues) {
+    // Initialize a new LinkedHashMap
+    const headerMap = new java.util.LinkedHashMap();
+
+    // Function to get the last value of a header key
+    const keyToEntryWithLastValue = key => {
+        const headerList = headers.getHeaderList(key);
+        const value = headerList && headerList.get(headerList.size() - 1);
+        return [key, value];
+    }
+
+    // Populate the headerMap based on the excludeNullValues flag
+    if (excludeNullValues == true) {
+        headerKeys.map(keyToEntryWithLastValue)
+            .filter(entry => entry[1] != null)
+            .forEach(entry => headerMap.put.apply(headerMap, entry));  
+    } else {
+        headerKeys.map(keyToEntryWithLastValue)
+            .forEach(entry => headerMap.put.apply(headerMap, entry));  
+    }
+
+    // Return the populated LinkedHashMap
+    return headerMap;
+}
+
+// Example usage:
+const headers = $s('headers');
+const headerKeys = ["host", "content-type", "date", "Authorization", "content-md5", "Accept"];
+const headerMap = createHeaderMap(headers, headerKeys, false);
+$co('headerMap',headerMap)
+// In your sender, selct "Use Map" and type in "headerMap" (no double quotes, just the word)
+