http/get_multipart/python/server/README.md

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# HTTP GET Arrow Data in multipart/mixed: Python Server Example

This directory contains an example of a Python HTTP server that sends a
`multipart/mixed` response to clients. The server:
1. Creates a list of record batches and populates it with synthesized data.
2. Listens for HTTP GET requests from clients.
3. Upon receiving a request, builds and sends an HTTP 200 `multipart/mixed`
   response containing:
   - A JSON part with metadata about the Arrow stream.
   - An Arrow stream part with the Arrow IPC stream of record batches.
   - A plain text part with a message containing timing information. This part
     is optional (included if `?include_footnotes` is present in the URL).

To run this example:

```sh
pip install pyarrow
python server.py
```

> [!NOTE]  
> This example uses Python's built-in
> [`http.server`](https://docs.python.org/3/library/http.server.html) module.
> This allows us to implement [chunked transfer
> encoding](https://en.wikipedia.org/wiki/Chunked_transfer_encoding) manually.
> Other servers may implement chunked transfer encoding automatically at the
> cost of an undesirable new layer of buffering. Arrow IPC streams already offer
> a natural way of chunking large amounts of tabular data. It's not a general
> requirement, but in this example each chunk corresponds to one Arrow record
> batch.