Hello,
Interceptors are a new feature in FF, and there is almost no documentation available for them.
I successfully built this interceptor, which I use to remove an attribute from a JSON payload.
While the end result seems simple, it required many trials and errors to make it work effectively. I would say that the secret lies in properly configuring the newOptions object with the necessary attributes.
Below is the code I've used. I hope it will be helpful to others.
// Automatic FlutterFlow imports
import '/backend/schema/structs/index.dart';
import '/backend/schema/enums/enums.dart';
import '/backend/supabase/supabase.dart';
import '/flutter_flow/flutter_flow_theme.dart';
import '/flutter_flow/flutter_flow_util.dart';
import '/custom_code/actions/index.dart'; // Imports other custom actions
import '/flutter_flow/custom_functions.dart'; // Imports custom functions
import 'package:flutter/material.dart';
// Begin custom action code
// DO NOT REMOVE OR MODIFY THE CODE ABOVE!
import 'dart:convert';
import '/backend/api_requests/api_interceptor.dart';
class removeAttributeInterceptor extends FFApiInterceptor {
@override
Future<ApiCallOptions> onRequest({
required ApiCallOptions options,
}) async {
// Parse the body JSON string into a Dart map and remove 'NameOfAttributeToRemove'
Map<String, dynamic> bodyObject = jsonDecode(options.body ?? '');
bodyObject.removeWhere((key, value) => key == 'NameOfAttributeToRemove');
String bodyString = jsonEncode(bodyObject);
// useful for debuging
// print('options: ' + options.toString() );
// recreate the options object with the modified body
final ApiCallOptions newOptions = ApiCallOptions(
callName: options.callName, // likely optional at this point
callType: options.callType,
bodyType: options.bodyType, // important for JSON body
apiUrl: options.apiUrl,
params: options.params,
headers: options.headers,
returnBody: options.returnBody, // usually set to true
body: bodyString, // modified body
);
// Return the modified options
return newOptions;
}
@override
Future<ApiCallResponse> onResponse({
required ApiCallResponse response,
required Future<ApiCallResponse> Function() retryFn,
}) async {
// Perform any necessary calls or modifications to the [response] prior to returning it
// Return the original response
return response;
}
}