enhance boolean handling to support null values across data connectors

Author: SerVitasik

adminforth/dataConnectors/clickhouse.ts

@@ -107,7 +107,7 @@ class ClickhouseConnector extends AdminForthBaseConnector implements IAdminForth
         }
         return dayjs(value).toISOString().split('T')[0];
       } else if (field.type == AdminForthDataTypes.BOOLEAN) {
-        return !!value;
+        return value === null ? null : !!value;
       } else if (field.type == AdminForthDataTypes.JSON) {
         if (field._underlineType.startsWith('String') || field._underlineType.startsWith('FixedString')) {
           try {
@@ -138,7 +138,7 @@ class ClickhouseConnector extends AdminForthBaseConnector implements IAdminForth
           return iso;
         }
       } else if (field.type == AdminForthDataTypes.BOOLEAN) {
-        return value ? 1 : 0;
+        return  value === null ? null : (value ? 1 : 0);
       } else if (field.type == AdminForthDataTypes.JSON) {
         // check underline type is text or string
         if (field._underlineType.startsWith('String') || field._underlineType.startsWith('FixedString')) {

adminforth/dataConnectors/mysql.ts

@@ -130,7 +130,7 @@ class MysqlConnector extends AdminForthBaseConnector implements IAdminForthDataS
     } else if (field.type == AdminForthDataTypes.TIME) {
       return value || null;
     } else if (field.type == AdminForthDataTypes.BOOLEAN) {
-      return !!value;
+      return value === null ? null : !!value;
     } else if (field.type == AdminForthDataTypes.JSON) {
       if (typeof value === 'string') {
         try {
@@ -158,7 +158,7 @@ class MysqlConnector extends AdminForthBaseConnector implements IAdminForthDataS
       }
       return dayjs(value).format('YYYY-MM-DD HH:mm:ss');
     } else if (field.type == AdminForthDataTypes.BOOLEAN) {
-      return value ? 1 : 0;
+      return value === null ? null : (value ? 1 : 0);
     } else if (field.type == AdminForthDataTypes.JSON) {
       if (field._underlineType === 'json') {
         return value;

adminforth/dataConnectors/postgres.ts

@@ -157,6 +157,10 @@ class PostgresConnector extends AdminForthBaseConnector implements IAdminForthDa
             return dayjs(value).toISOString().split('T')[0];
         }
 
+        if (field.type == AdminForthDataTypes.BOOLEAN) {
+            return value === null ? null : !!value;
+        } 
+
         if (field.type == AdminForthDataTypes.JSON) {
             if (typeof value == 'string') {
                 try {
@@ -188,7 +192,7 @@ class PostgresConnector extends AdminForthBaseConnector implements IAdminForthDa
                 return dayjs(value).toISOString();
             }
         } else if (field.type == AdminForthDataTypes.BOOLEAN) {
-            return value ? 1 : 0;
+            return value === null ? null : (value ? 1 : 0);
         } else if (field.type == AdminForthDataTypes.JSON) {
             if (field._underlineType == 'json') {
                 return value;