added operation type header_value

Author: headri

converter_app/converters.py

@@ -297,11 +297,25 @@ def _run_operation(self, rows, operation):
                 str_value = operation.get('value')
             elif operation.get('type') == 'metadata_value':
                 str_value = self.input_tables[int(operation.get('table'))]['metadata'].get(operation.get('value'))
+            elif operation.get('type') == 'header_value':
+                table = 0
+                if operation.get('table') is not None:
+                    table = int(operation.get('table'))
+                line = operation.get('line')
+                pattern = operation.get('regex')
+                if line is not None and pattern is not None:
+                    str_value = self.input_tables[table]['header'][int(operation.get('line'))-1]
+                    match = re.search(pattern, str_value)
+                    if match is not None:
+                        if len(match.regs) > 1:
+                            str_value = match[1]
+                        else:
+                            str_value = match[0]
             else:
                 raise ValueError(f"Unknown operation type: {operation.get('type')}")
             try:
                 op_value = float(str_value)
-            except TypeError:
+            except (TypeError, ValueError):
                 if operation.get('operator') in ('+', '-'):
                     op_value = 0
                 else: