Install/Use rbenv (Ruby) on Windows 10 Linux WSL(2)

You can have a complete ruby virtual development environment under Windows 10 Linux Subsystem (WSL2). Here is in few steps how to do it

1. Add a user (eg hleclerc), your install will be only for this user not for system wide

# adduser hleclerc
# usermod -aG sudo hleclerc

2. Install mandatory packages

# sudo apt-get update
# sudo apt-get install -y \
build-essential \
git \
libreadline-dev \
libssl-dev \
zlib1g-dev

libreadline is important for rdoc your build will fail if not installed

3. su with this user

# su -l hleclerc

4. Get rbenv

# git clone https://github.com/rbenv/rbenv.git ~/.rbenv

5. Get rbenv plugins

# git clone https://github.com/rbenv/ruby-build.git ~/.rbenv/plugins/ruby-build
# git clone https://github.com/rkh/rbenv-whatis.git ~/.rbenv/plugins/rbenv-whatis
# git clone https://github.com/rkh/rbenv-use.git ~/.rbenv/plugins/rbenv-use

6. Compile rbenv utility

# cd ~/.rbenv && src/configure && make -C src

7. add rbenv to path

# echo 'export PATH=$HOME/.rbenv/bin:$PATH' >> ~/.bash_profile

8. set completion > edit ~/.bash_profile add at the end of file:

# eval "$(rbenv init -)"

9. exit from user and re-su to check all is ok

# exit
# su -l hleclerc

-l is important to simulate a login

10. check rbenv (list all available ruby versions)

# rbenv install -l

11. install a version of ruby

# rbenv install 2.7.6

It will make some times….
you can check the log in /tmp/ruby-build.xx.log xxx is a timestamp. Check for errors if it fails

12. Install shims after an installation of a version

# rbenv rehash

13. list installed version

# rbenv versions

14. set the local version of

# rbenv local 2.7.6

or
15. set global version of ruby

# rbenv global 2.7.6

16. Use a version of ruby (rbenv-use plugin)

rbenv use 2.7.6

17. Show the version of ruby

# ruby -v

18. Show the version of gem

# gem -v
# which gem

19. Write a simple web server in ruby

create a file myserver.rb with this code

require ‘socket’ # Provides TCPServer and TCPSocket classes
# Initialize a TCPServer object that will listen
# on localhost:2345 for incoming connections.
server = TCPServer.new(‘localhost’, 2345)
# loop infinitely, processing one incoming
# connection at a time.
loop do
# Wait until a client connects, then return a TCPSocket
 # that can be used in a similar fashion to other Ruby
 # I/O objects. (In fact, TCPSocket is a subclass of IO.)
 socket = server.accept
# Read the first line of the request (the Request-Line)
 request = socket.gets
# Log the request to the console for debugging
 STDERR.puts request
response = “Hello World!\n”
# We need to include the Content-Type and Content-Length headers
 # to let the client know the size and type of data
 # contained in the response. Note that HTTP is whitespace
 # sensitive, and expects each header line to end with CRLF (i.e. “\r\n”)
 socket.print “HTTP/1.1 200 OK\r\n” +
 “Content-Type: text/plain\r\n” +
 “Content-Length: #{response.bytesize}\r\n” +
 “Connection: close\r\n”
# Print a blank line to separate the header from the response body,
 # as required by the protocol.
 socket.print “\r\n”
# Print the actual response body, which is just “Hello World!\n”
 socket.print response
# Close the socket, terminating the connection
 socket.close
end

20. test your server

ruby myserver.rb

then try opening http://localhost:2345/bashonwindows in your browser

You should see GET /anything HTTP/1.1 in shell and Hello World in browser

Happy Ruby Coding