Fix test connection with codemirror and extra (#35122)

airflow/www/static/js/connection_form.js

@@ -29,6 +29,9 @@ const configTestConnection = getMetaValue("config_test_connection")
 const restApiEnabled = getMetaValue("rest_api_enabled") === "True";
 const connectionTestUrl = getMetaValue("test_url");
 
+// Define editor var which may get populated if extra field exists on the connection
+let editor;
+
 function decode(str) {
   return new DOMParser().parseFromString(str, "text/html").documentElement
     .textContent;
@@ -330,6 +333,11 @@ $(document).ready(() => {
   $("#test-connection").on("click", (e) => {
     e.preventDefault();
     hideAlert();
+    // save the contents of the CodeMirror editor to the textArea if it is populated
+    // (i.e., connection type has extra field)
+    if (Object.prototype.hasOwnProperty.call(editor, "save")) {
+      editor.save();
+    }
     $.ajax({
       url: connectionTestUrl,
       type: "post",
@@ -356,16 +364,18 @@ $(document).ready(() => {
 
   // Change conn.extra TextArea widget to CodeMirror
   const textArea = document.getElementById("extra");
-  const editor = CodeMirror.fromTextArea(textArea, {
+  editor = CodeMirror.fromTextArea(textArea, {
     mode: { name: "javascript", json: true },
     gutters: ["CodeMirror-lint-markers"],
     lineWrapping: true,
     lint: true,
   });
 
-  // beautify JSON
+  // beautify JSON but only if it is not equal to default value of empty string
   const jsonData = editor.getValue();
-  const data = JSON.parse(jsonData);
-  const formattedData = JSON.stringify(data, null, 2);
-  editor.setValue(formattedData);
+  if (jsonData !== "") {
+    const data = JSON.parse(jsonData);
+    const formattedData = JSON.stringify(data, null, 2);
+    editor.setValue(formattedData);
+  }
 });