fix: add backwards compatibility to ElementMetadata (#1526)
Fixes https://github.com/Unstructured-IO/unstructured-api/issues/237
The problem:
The `ElementMetadata` class was not able to ignore fields that it didn't
know about. This surfaced in `partition_via_api`, when the hosted api
schema is newer than the local `unstructured` version. In
`ElementMetadata.from_json()` we get errors such as `TypeError:
__init__() got an unexpected keyword argument 'parent_id'`.
The fix:
The `from_json` methods for these dataclasses should drop any unexpected
fields before calling `__init__`.
To verify:
This shouldn't throw an error
```
from unstructured.staging.base import elements_from_json
import json
test_api_result = json.dumps([
{
"type": "Title",
"element_id": "2f7cc75f6467bba468022c4c2875335e",
"metadata": {
"filename": "layout-parser-paper.pdf",
"filetype": "application/pdf",
"page_number": 1,
"new_field": "foo",
},
"text": "LayoutParser: A Uniļ¬ed Toolkit for Deep Learning Based Document Image Analysis"
}
])
elements = elements_from_json(text=test_api_result)
print(elements)
```
unstructured
f34c277b - fix: add backwards compatibility to ElementMetadata (#1526)
