fix: add_texts method of Weaviate vector store creats wrong embeddings (#4933)
# fix a bug in the add_texts method of Weaviate vector store that creats
wrong embeddings
The following is the original code in the `add_texts` method of the
Weaviate vector store, from line 131 to 153, which contains a bug. The
code here includes some extra explanations in the form of comments and
some omissions.
```python
for i, doc in enumerate(texts):
# some code omitted
if self._embedding is not None:
# variable texts is a list of string and doc here is just a string.
# list(doc) actually breaks up the string into characters.
# so, embeddings[0] is just the embedding of the first character
embeddings = self._embedding.embed_documents(list(doc))
batch.add_data_object(
data_object=data_properties,
class_name=self._index_name,
uuid=_id,
vector=embeddings[0],
)
```
To fix this bug, I pulled the embedding operation out of the for loop
and embed all texts at once.
Co-authored-by: Shawn91 <zyx199199@qq.com>
Co-authored-by: Dev 2049 <dev.dev2049@gmail.com>