postEntity method

Future<String?> postEntity(String entity, Map<String, dynamic> payload, { String? filterByField, String? filterValue, String? mainField, })

Sends a POST request to create a record in a Dynamics 365 entity.

Parameters:

• entity: the entity name (e.g., SalesOrderHeaders, SalesOrderLines)
• payload: a map of field names and values to create
• filterByField / filterValue: optional, not usually used with POST
• mainField: optional, the field to return from the response (like salesOrderId)

Returns:

• the value of mainField if provided and returned by D365
• null if failed or mainField not set

Implementation

Future<String?> postEntity(String entity,
    Map<String, dynamic> payload, {
      String? filterByField,
      String? filterValue,
      String? mainField,

      /// like salesOrderId
    }) async {
  final token = await getAccessToken();
  if (token == null) return null;

  final url = (filterByField != null &&
      filterByField.isNotEmpty &&
      filterValue != null &&
      filterValue.isNotEmpty)
      ? Uri.parse(
      "$resource/data/$entity?\$filter=$filterByField eq '$filterValue'")
      : Uri.parse("$resource/data/$entity");

  final response = await http.post(
    url,
    headers: {
      'Authorization': 'Bearer $token',
      'Content-Type': 'application/json',
      'Accept': 'application/json',
    },
    body: json.encode(payload),
  );

  if (response.statusCode == 201 || response.statusCode == 200) {
    if (mainField != null) {
      final data = jsonDecode(response.body);
      return data[mainField];
    }
    else {
      return null;
    }
  } else {
    print("❌ Failed to post $entity: ${response.statusCode} - ${response
        .body}");
    return null;
  }
}