Python httpx.stream_bytes() Guide: Stream Bytes

Python's httpx library is a powerful tool for making HTTP requests. One of its standout features is the ability to stream data. This guide focuses on httpx.stream_bytes(), a method for streaming byte data from HTTP responses.

What is httpx.stream_bytes()?

The httpx.stream_bytes() method allows you to stream byte data from an HTTP response. This is particularly useful when dealing with large files or data streams that you don't want to load entirely into memory.

Why Use httpx.stream_bytes()?

Streaming byte data is essential for handling large files or continuous data streams. It helps in managing memory efficiently and ensures that your application remains responsive.

How to Use httpx.stream_bytes()

To use httpx.stream_bytes(), you first need to make an HTTP request using the httpx library. Then, you can stream the byte data from the response.

import httpx

# Make an HTTP GET request
with httpx.stream("GET", "https://example.com/large-file") as response:
    # Stream the byte data
    for chunk in response.stream_bytes():
        print(chunk)
    

In this example, the stream_bytes() method is used to stream byte data from the response. Each chunk of data is printed as it is received.

Example Code and Output

Let's look at a complete example that demonstrates how to use httpx.stream_bytes() to download a large file.

import httpx

# URL of the large file
url = "https://example.com/large-file"

# Make an HTTP GET request and stream the byte data
with httpx.stream("GET", url) as response:
    with open("large-file.bin", "wb") as file:
        for chunk in response.stream_bytes():
            file.write(chunk)
    

This code downloads a large file from the specified URL and writes it to a local file named large-file.bin. The file is written in chunks as the data is streamed.

Handling Errors and Timeouts

When streaming data, it's important to handle errors and timeouts properly. The httpx library provides mechanisms for setting timeouts and handling exceptions.

import httpx

try:
    with httpx.stream("GET", "https://example.com/large-file", timeout=10.0) as response:
        for chunk in response.stream_bytes():
            print(chunk)
except httpx.TimeoutException:
    print("Request timed out")
except httpx.RequestError as e:
    print(f"An error occurred: {e}")
    

In this example, a timeout of 10 seconds is set for the request. If the request takes longer than 10 seconds, a TimeoutException is raised. Other request errors are caught and handled as well.

Conclusion

The httpx.stream_bytes() method is a powerful tool for streaming byte data from HTTP responses. It is particularly useful for handling large files or continuous data streams. By using this method, you can manage memory efficiently and ensure that your application remains responsive.

For more information on related topics, check out our guides on Python httpx.stream_json(), Python httpx.stream_text(), and Python httpx.Request().