download_retry.py

A simple Python command-line tool to repeatedly attempt downloading a binary file from a URL until successful or until a timeout is reached.

Features

• Downloads binary data from a given URL
• Skips SSL certificate validation by default (--insecure true)
• Retries every delta_t seconds until max_t seconds have elapsed
• Saves the result to a specified output file
• Returns exit code 0 on success, 1 on failure

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Requirements

• Python 3.6+
• requests package

Install dependencies using:

pip install -r requirements.txt

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Installation

Clone the repository.

git clone git@github.com:gilweis/download_retry.git
cd download_retry

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Usage

python -m download_retry --url --delta_t --max_t --out <output_filename> [--insecure true|false]

Arguments

Argument	Description	Example
--url	The URL to download from	https://example.com/file.bin
--delta_t	Time between retries in seconds	5
--max_t	Maximum total wait time in seconds	60
--out	Output filename	file.bin
--insecure	Skip SSL verification (true by default)	true or false

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Examples

Default (insecure=True):

Skips SSL certificate verification:

python -m download_retry
--url "https://my.server.local/firmware.bin"
--delta_t 3
--max_t 60
--out firmware.bin

Enforce SSL certificate verification (insecure=False):

python -m download_retry
--url "https://secure.example.com/file.bin"
--delta_t 3
--max_t 60
--out secure.bin
--insecure false

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Exit Codes

• 0: File downloaded successfully
• 1: Failed to download within time limit

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Testing

To run tests:

1. Install test requirements:

pip install pytest

2. Run tests:

pytest tests/

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Build and Install

To build source and wheel distributions:

python -m build

If you don't have the build tool installed:

pip install build

To install the package locally:

pip install .

To upload to PyPI (optional):

pip install twine twine upload dist/*

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Warning

By default, SSL certificate validation is disabled using --insecure true. This may expose you to man-in-the-middle attacks. Use --insecure false to enforce SSL verification when downloading from public or sensitive endpoints.

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License

MIT License

Version

0.1.2