Alex Klein | 2b23672 | 2019-06-19 15:44:26 -0600 | [diff] [blame^] | 1 | # -*- coding: utf-8 -*- |
| 2 | # Copyright 2019 The Chromium OS Authors. All rights reserved. |
| 3 | # Use of this source code is governed by a BSD-style license that can be |
| 4 | # found in the LICENSE file. |
| 5 | |
| 6 | """Validation helpers for simple input validation in the API.""" |
| 7 | |
| 8 | from __future__ import print_function |
| 9 | |
| 10 | import os |
| 11 | |
| 12 | from chromite.lib import cros_build_lib |
| 13 | from chromite.lib import cros_logging as logging |
| 14 | |
| 15 | from google.protobuf import message as protobuf_message |
| 16 | |
| 17 | |
| 18 | def _value(field, message): |
| 19 | """Helper function to fetch the value of the field. |
| 20 | |
| 21 | Args: |
| 22 | field (str): The field name. Can be nested via . separation. |
| 23 | message (Message): The protobuf message it is being fetched from. |
| 24 | |
| 25 | Returns: |
| 26 | str|None|int|list|Message|bool - The value of the field. |
| 27 | """ |
| 28 | value = message |
| 29 | for part in field.split('.'): |
| 30 | if not isinstance(value, protobuf_message.Message): |
| 31 | value = None |
| 32 | break |
| 33 | |
| 34 | try: |
| 35 | value = getattr(value, part) |
| 36 | except AttributeError as e: |
| 37 | cros_build_lib.Die('Invalid field: %s', e.message) |
| 38 | |
| 39 | return value |
| 40 | |
| 41 | #pylint: disable=docstring-misnamed-args |
| 42 | def exists(*fields): |
| 43 | """Validate that the paths in |fields| exist. |
| 44 | |
| 45 | Args: |
| 46 | fields (str): The fields being checked. Can be . separated nested |
| 47 | fields. |
| 48 | """ |
| 49 | assert fields |
| 50 | |
| 51 | def decorator(func): |
| 52 | def _exists(input_proto, *args, **kwargs): |
| 53 | for field in fields: |
| 54 | logging.debug('Validating %s exists.', field) |
| 55 | |
| 56 | value = _value(field, input_proto) |
| 57 | if not value or not os.path.exists(value): |
| 58 | cros_build_lib.Die('%s path does not exist: %s' % (field, value)) |
| 59 | |
| 60 | return func(input_proto, *args, **kwargs) |
| 61 | |
| 62 | return _exists |
| 63 | |
| 64 | return decorator |
| 65 | |
| 66 | |
| 67 | #pylint: disable=docstring-misnamed-args |
| 68 | def require(*fields): |
| 69 | """Verify |fields| have all been set. |
| 70 | |
| 71 | Args: |
| 72 | fields (str): The fields being checked. May be . separated nested |
| 73 | fields. |
| 74 | """ |
| 75 | assert fields |
| 76 | |
| 77 | def decorator(func): |
| 78 | def _require(input_proto, *args, **kwargs): |
| 79 | for field in fields: |
| 80 | logging.debug('Validating %s is set.', field) |
| 81 | |
| 82 | value = _value(field, input_proto) |
| 83 | if not value: |
| 84 | cros_build_lib.Die('%s is required.', field) |
| 85 | |
| 86 | return func(input_proto, *args, **kwargs) |
| 87 | |
| 88 | return _require |
| 89 | |
| 90 | return decorator |