Vesper - HTTP Framework for Bash Shell

vesper is a collection of shell functions to make it super easy to generate valid http responses. Vesper is not a web server itself, its just the framework to parse http requests and generate valid responses.

This is crazy, who needs a http framework for unix shell?

That is a very good question! If you would have asked me that question a year ago, I would have argued: nobody. Now, I am not sure anymore. How will sh/bash scripts work in the future of cloud and serverless? Consider reading my blog Introducing Vesper - HTTP Framework for Unix Shell.

Get Started

Hello World

source "vesper.sh"

# parses the http request
http_request

# generate the response
http_response StatusOK "text/plain"
echo 'Hello World'
echo $HTTP_REQUEST_URI

Generate an Image

source "vesper.sh"

http_response StatusOK "image/jpeg"
echo "James Bond" | convert -font Arial -pointsize 72 -fill white -background black text:- -trim png:- >&1

Seeing is believing

# hello world example
ncat -lk -p 8081 --sh-exec examples/helloworld.sh

# json example
ncat -lk -p 8081 --sh-exec examples/json.sh

# image example
ncat -lk -p 8081 --sh-exec examples/image.sh

# pdf example
ncat -lk -p 8081 --sh-exec examples/pdf.sh

# file streaming example
ncat -lk -p 8081 --sh-exec examples/file_stream.sh

# router example
ncat -lk -p 8081 --sh-exec examples/router.sh

Examples

• Text
• JSON
• Image
• PDF
• File Stream
• Router

To see all the examples in place justs run:

Start the server

# download the test pdf
wget http://tiswww.case.edu/php/chet/bash/rose94.pdf

# start the server
ncat -lk -p 8081 --sh-exec ./examples/router.sh

Visit the url localhost:8081

Dependencies

• ncat - used to execute the bash scripts on incoming requests
• cat - used to pipe file content
• file - used to determine the mime type
• stat - used to determine the file size

Debian

apt-get install ncat
apt-get install file

Centos

yum install nmap
yum install file

Mac

brew install nmap

FAQ

Why is the project named vesper?

Popular web frameworks like martini and gin are named after cocktails and one of James Bond's famous cocktails is called vesper.

Is vesper production ready?

Its build on tooling that is around for decades. The foundation is battle-tested. While this is the case, its not designed for web-scale workloads.

Should I switch from my popular http framework X to vesper?

Most likely not

Are there limitations

At this point, its only tested with http GET methods

Open questions

• What is the best way to handle execution errors?
• What is the stable way to verify http query params?

Authors

• Christoph Hartmann - Research & Prototype - chris-rock

See also the list of contributors who participated in this project.

Sponsors

The research and the development was sponsored by mondoo

License

This project is licensed under the Apache 2 License - see the LICENSE.md file for details

Acknowledgments

shinatra and bashttpd also prototyped around http in bash.