Enhance set_record function to check current value before updating and improve response messages for clarity

app.py

@@ -5,6 +5,7 @@ from flask_httpauth import HTTPBasicAuth
 from base64 import b64encode
 from requests import get, put, delete
 from os import getenv
+import jmespath
 
 # Define global variables for MIAB host and auth header, to be set during authentication
 MIAB_HOST = getenv('MIAB_HOST', 'localhost')
@@ -37,6 +38,16 @@ def set_record(qname, rtype, value = None):
         value = request.data.decode()
     
     url = f'https://{MIAB_HOST}/admin/dns/custom/{qname}/{rtype}'
+
+    # Check the currect value
+    resp = get(url, headers={'Authorization': MIAB_AUTH_HEADER})
+    
+    if resp.status_code == 200:
+        current_value = jmespath.compile('[0].value').search(resp.json())
+        if current_value == value:
+            return f'OK, no change'  # No change needed
+
+    # Values are different or record does not exist, proceed to set the new value
     resp = put(url, headers={'Authorization': MIAB_AUTH_HEADER, 'Content-Type': 'text/plain'}, data=value)
     
     # Propagate 400-499 as is, 500+ as 502
@@ -47,10 +58,10 @@ def set_record(qname, rtype, value = None):
             status = 502
         else:
             status = 500
-        return Response(f'ERROR\n', status=status)
+        return Response(f'ERROR: {resp.status_code}\n', status=status)
     
     # Success
-    return f'OK\n'
+    return f'OK, record set'
 
 @app.route('/api/deleterecord/<qname>/<rtype>', methods=['GET', 'DELETE'])
 @auth.login_required
@@ -70,7 +81,7 @@ def delete_record(qname, rtype):
         return Response(f'ERROR\n', status=status)
     
     # Success
-    return f'OK\n'
+    return f'OK, record deleted.\n'
 
 @app.route('/api/listrecords', methods=['GET'], defaults={'qname': None, 'rtype': None})
 @app.route('/api/listrecords/<qname>', methods=['GET'], defaults={'rtype': None})