Converting A Blob Into A Bytearray In Python Flask

Last Updated : 26 Mar, 2024

In web development, dealing with binary data, such as images or files, is a common requirement. Blobs (Binary Large Objects) are a representation of binary data, and at times, you may need to convert a blob into a more manageable data structure, like a Python bytearray. This article will guide you through the process of converting a blob into a bytearray in the context of a Python Flask application.

sample.xml

Screenshot-2024-03-15-124902

Converting Blob to Bytearray in Flask

Below are the step-by-step procedure to convert blob to bytearray in Python Flask:

Create a Virtual Environment

We will create the virtual environment and activate it by using the following commands:

python -m venv venv
venv\Scripts\activate

Now, We will install the following libraries before starting:

pip install flask

File Structure

Screenshot-2024-03-15-122257

Set Up a Flask Application

Create a file named app.py in the project directory and initialize a Flask application.

Python3

from flask import Flask, render_template, request
import io
import base64

app = Flask(__name__)


@app.route('/')
def index():
    return render_template('index.html')


@app.route('/upload', methods=['POST'])
def upload():
    blob_file = request.files['blob_file']
    if blob_file:
        blob_data = blob_file.read()
        byte_array = bytearray(blob_data)  # Convert Blob to Bytearray
        encoded_data = base64.b64encode(bytes(byte_array)).decode(
            'utf-8')  # Encode bytearray to base64
        return (encoded_data)
    return "No file uploaded."


if __name__ == '__main__':
    app.run(debug=True)

Create HTML Template

Inside the templates directory, create a file named index.html.

HTML

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Upload Blob</title>
</head>
<body>
    <form action="/upload" method="post" enctype="multipart/form-data">
        <input type="file" name="blob_file" accept=".txt,.pdf,.jpg,.png,.gif">
        <button type="submit">Upload</button>
    </form>
</body>
</html>

Output

Screenshot-2024-03-15-122542

Run the Program

Save all the changes and run the Flask application:

python app.py

Visit http://127.0.0.1:5000/ in your web browser. You should see a file upload form. Choose a file and click the “Upload” button. The application will convert the uploaded Blob into a Bytearray.

Output:

ezgifcom-resize-(2)

Conclusion

Converting a blob into a bytearray in a Python Flask application is a straightforward process. By fetching the blob data from your data source, converting it using Python’s bytearray constructor, and integrating it into your Flask application, you can effectively manage binary data within your web application. Adjust the provided code snippets based on your specific use case and database setup.

Suggest improvement

Convert a Bytes Array into Json Format in Python

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