How can I start a socket REPL in Clojure 1.8 from leiningen or boot?

Question

In the following link http://clojure.org/reference/repl_and_main#_launching_a_socket_server

it has detailed info about how to start socket REPL form java, but since I am using lein, so how to start from lein. If start from boot is good to run, I could also try to use boot.

Answer 1

To start a socket repl, you need to pass this option to the JVM

-Dclojure.server.repl="{:port 5555 :accept clojure.core.server/repl}"

In Leiningen, add this to your project.clj.

:jvm-opts ["-Dclojure.server.repl={:port 5555 :accept clojure.core.server/repl}"] ; notice that the map is not quoted.

and in Boot, export the environment variable BOOT_JVM_OPTIONS

export BOOT_JVM_OPTIONS='-Dclojure.server.repl="{:port 5555 :accept clojure.core.server/repl}"'

Once your REPL is running, you can run telnet from a different terminal to connect to the socket REPL. REPLception!

$ telnet 127.0.0.1 5555
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
user=> (+ 1 1)
2
user=>