Fix issue with delete_order

src/valr_python/rest_base.py

@@ -1019,4 +1019,4 @@ def delete_order(self, currency_pair: Union[str, CurrencyPair], order_id: str =
             data["orderId"] = order_id
         else:
             data["customerOrderId"] = customer_order_id
-        return self._do('DELETE', '/v1/orders/order', data=data, is_authenticated=True, subaccount_id=subaccount_id)
+        return self._do_delete('DELETE', '/v1/orders/order', data=data, is_authenticated=True, subaccount_id=subaccount_id)

src/valr_python/rest_client.py

@@ -77,12 +77,15 @@ def _do(self, method: str, path: str, data: Optional[Dict] = None, params: Optio
 
         try:
             res.raise_for_status()
-            e = res.json()
-            self._raise_for_api_error(e)
-            # provide warning with bundled response dict for incomplete transactions
-            if res.status_code == 202:
-                warnings.warn(IncompleteOrderWarning(data=e, message="Order processing incomplete"))
-            return e
+            if res.text:
+                e = res.json()
+                self._raise_for_api_error(e)
+                # provide warning with bundled response dict for incomplete transactions
+                if res.status_code == 202:
+                    warnings.warn(IncompleteOrderWarning(data=e, message="Order processing incomplete"))
+                return e
+            else:
+                return res.raise_for_status()
         except HTTPError as he:
             print(he)
             if res.status_code == 429:
@@ -107,3 +110,26 @@ def _do(self, method: str, path: str, data: Optional[Dict] = None, params: Optio
         except JSONDecodeError as jde:
             raise RESTAPIException(res.status_code,
                                    f'valr-python: unknown API error. HTTP ({res.status_code}): {jde.msg}')
+
+
+    def _do_delete(self, method: str, path: str, data: Optional[Dict] = None, params: Optional[Dict] = None,
+            is_authenticated: bool = False, subaccount_id: str = '') -> Optional[Union[List, Dict]]:
+        """Executes API request and returns the response.
+
+        Includes HTTP 429 handling by honouring VALR's 429 Retry-After header cool-down.
+        """
+        headers = {}
+        if data:
+            data = json.dumps(data, cls=DecimalEncoder)  # serialize decimals as str
+            headers["Content-Type"] = "application/json"
+        params_str = parse.urlencode(params, safe=":") if params else None
+        if is_authenticated:
+            # todo - fix data processing in valr headers
+            headers.update(_get_valr_headers(api_key=self.api_key, api_secret=self.api_secret, method=method,
+                                             path=f'{path}?{params_str}' if params_str else path, data=data,
+                                             subaccount_id=subaccount_id))
+        url = self._base_url + '/' + path.lstrip('/')
+        args = dict(timeout=self._timeout, data=data, headers=headers)
+        if params_str:
+            args['params'] = params_str
+        return self._session.request(method, url, **args)