create func

src/server/models/user.js

@@ -285,12 +285,10 @@ module.exports = function(crowi) {
     });
   };
 
-  userSchema.methods.removeFromAdmin = function(callback) {
+  userSchema.methods.removeFromAdmin = async function() {
     debug('Remove from admin', this);
     this.admin = 0;
-    this.save((err, userData) => {
-      return callback(err, userData);
-    });
+    return this.save();
   };
 
   userSchema.methods.makeAdmin = async function() {

src/server/routes/admin.js

@@ -459,6 +459,7 @@ module.exports = function(crowi, app) {
     });
   };
 
+  // TODO delete
   actions.user.removeFromAdmin = function(req, res) {
     const id = req.params.id;
     User.findById(id, (err, userData) => {

src/server/routes/apiv3/users.js

@@ -164,7 +164,7 @@ module.exports = (crowi) => {
 
     try {
       const userData = await User.findById(id);
-      // await userData.makeAdmin();
+      await userData.removeFromAdmin();
       return res.apiv3({ userData });
     }
     catch (err) {