This is a middleware for Scrapy framework. It allows to set random User-Agent for each request.

Create a text file with one user agent per line.

This way you can grep user agents from Nginx logs:

egrep -h -o '"[^"]+" "[^"]+"$' * | cut -d '"' -f 2 | sort -u > user-agents.txt

Call this file user-agents.txt or use another name and write it's path in the USER_AGENTS_LIST_FILE setting.

Then add it into the middleware list, and remove default middleware:

DOWNLOADER_MIDDLEWARES = {
 # we'll turn off standart user agent middleware
 'scrapy.contrib.downloadermiddleware.useragent.UserAgentMiddleware': None,
 'scrapy_useragents.middleware.UserAgentsMiddleware': 400,
}

Author of this project is Alexander Artemenko. You are welcomed to send patches and pull requests to the GitHub.