forked from Archives/langchain
63aa28e2a6
### Summary
Allows users to pass in `**unstructured_kwargs` to Unstructured document
loaders. Implemented with the `strategy` kwargs in mind, but will pass
in other kwargs like `include_page_breaks` as well. The two currently
supported strategies are `"hi_res"`, which is more accurate but takes
longer, and `"fast"`, which processes faster but with lower accuracy.
The `"hi_res"` strategy is the default. For PDFs, if `detectron2` is not
available and the user selects `"hi_res"`, the loader will fallback to
using the `"fast"` strategy.
### Testing
#### Make sure the `strategy` kwarg works
Run the following in iPython to verify that the `"fast"` strategy is
indeed faster.
```python
from langchain.document_loaders import UnstructuredFileLoader
loader = UnstructuredFileLoader("layout-parser-paper-fast.pdf", strategy="fast", mode="elements")
%timeit loader.load()
loader = UnstructuredFileLoader("layout-parser-paper-fast.pdf", mode="elements")
%timeit loader.load()
```
On my system I get:
```python
In [3]: from langchain.document_loaders import UnstructuredFileLoader
In [4]: loader = UnstructuredFileLoader("layout-parser-paper-fast.pdf", strategy="fast", mode="elements")
In [5]: %timeit loader.load()
247 ms ± 369 µs per loop (mean ± std. dev. of 7 runs, 1 loop each)
In [6]: loader = UnstructuredFileLoader("layout-parser-paper-fast.pdf", mode="elements")
In [7]: %timeit loader.load()
2.45 s ± 31 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)
```
#### Make sure older versions of `unstructured` still work
Run `pip install unstructured==0.5.3` and then verify the following runs
without error:
```python
from langchain.document_loaders import UnstructuredFileLoader
loader = UnstructuredFileLoader("layout-parser-paper-fast.pdf", mode="elements")
loader.load()
```
45 lines
1.8 KiB
Markdown
45 lines
1.8 KiB
Markdown
# Unstructured
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This page covers how to use the [`unstructured`](https://github.com/Unstructured-IO/unstructured)
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ecosystem within LangChain. The `unstructured` package from
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[Unstructured.IO](https://www.unstructured.io/) extracts clean text from raw source documents like
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PDFs and Word documents.
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This page is broken into two parts: installation and setup, and then references to specific
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`unstructured` wrappers.
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## Installation and Setup
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- Install the Python SDK with `pip install "unstructured[local-inference]"`
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- Install the following system dependencies if they are not already available on your system.
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Depending on what document types you're parsing, you may not need all of these.
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- `libmagic-dev`
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- `poppler-utils`
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- `tesseract-ocr`
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- `libreoffice`
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- If you are parsing PDFs using the `"hi_res"` strategy, run the following to install the `detectron2` model, which
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`unstructured` uses for layout detection:
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- `pip install "detectron2@git+https://github.com/facebookresearch/detectron2.git@v0.6#egg=detectron2"`
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- If `detectron2` is not installed, `unstructured` will fallback to processing PDFs
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using the `"fast"` strategy, which uses `pdfminer` directly and doesn't require
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`detectron2`.
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## Wrappers
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### Data Loaders
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The primary `unstructured` wrappers within `langchain` are data loaders. The following
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shows how to use the most basic unstructured data loader. There are other file-specific
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data loaders available in the `langchain.document_loaders` module.
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```python
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from langchain.document_loaders import UnstructuredFileLoader
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loader = UnstructuredFileLoader("state_of_the_union.txt")
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loader.load()
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```
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If you instantiate the loader with `UnstructuredFileLoader(mode="elements")`, the loader
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will track additional metadata like the page number and text type (i.e. title, narrative text)
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when that information is available.
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