Short solution needed: "How to log request body with Lua" (nginx-lua)

[nonunicorn]

Please help us write most modern and shortest code solution for this issue: How to log request body with Lua (technology: nginx-lua)

Fast way

Just write the code solution in the comments.

Prefered way

1. Create pull request with a new code file inside inbox folder.
2. Don't forget to use comments to make solution explained.
3. Link to this issue in comments of pull request.