| # Licensed to the Apache Software Foundation (ASF) under one or more |
| # contributor license agreements. See the NOTICE file distributed with |
| # this work for additional information regarding copyright ownership. |
| # The ASF licenses this file to You under the Apache License, Version 2.0 |
| # (the "License"); you may not use this file except in compliance with |
| # the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| |
| class Loader(object): |
| """ |
| Base class for ARIA loaders. |
| |
| Loaders extract a document by consuming a document source. |
| |
| Though the extracted document is often textual (a string or string-like data), loaders may |
| provide any format. |
| |
| Loaders can also calculate the "canonical location" of what they are loading, which is a |
| globally unique reference that can be used as a cache key. Examples include absolute file paths |
| and de-relativized URIs. Note that calculating the canonical location can be very costly |
| (for example, hitting various URLs until finding an existing one), and thus it's a good idea |
| to cache the canonical location per loader context. |
| """ |
| |
| def open(self): |
| pass |
| |
| def close(self): |
| pass |
| |
| def load(self): |
| raise NotImplementedError |
| |
| def get_canonical_location(self): |
| raise NotImplementedError |