How can I do web programming with Lisp or Scheme?

Question

I usually write web apps in PHP, Ruby or Perl. I am starting the study of Scheme and I want to try some web project with this language. But I can't find what is the best environment for this.

I am looking for the following features:

• A simple way of get the request parameters (something like: get-get #key, get-post #key, get-cookie #key).
• Mysql access.
• HTML Form generators, processing, validators, etc.
• Helpers for filter user input data (something like htmlentities, escape variables for put in queries, etc).
• FLOSS.
• And GNU/Linux friendly.

So, thanks in advance to all replies.

Answer 1

Racket has everything that you need. See the Racket web server tutorial and then the documentation. The web server has been around for a while, and it has a lot of features. Probably the only thing that is not included is a mysql interface, but that exists as a package on PLaneT (Racket package distribution tool).

UPDATE: Racket now comes with DB support, works with several DBs including mysql.

Answer 2

I use my own, customized version of Scheme, derived from MzScheme. It has a new, simple web-application framework, a built-in web-server (not the one that comes with MzScheme) and ODBC libraries. (http://spark-scheme.wikispot.org/Web_applications). The documentation may not be exhaustive, as this is more of a personal tool. But there are lots of sample code in the code repository.

Answer 3

Let's see what can be done with Common Lisp.

The state of the Common Lisp ecosystem (2015) and the Awesome Common Lisp list show us a couple of modern frameworks (Caveman, Lucerne, all built on the new Clack web application server, an interface for Hunchentoot and other servers). Let's discuss with our own findings.

update: a bit later, I found out Snooze, by the creator of Sly or Emacs' Yasnippet, and had a much better impression than say Caveman. Declaring endpoints is just like declaring functions, so some things that were tedious in Caveman are obvious in Snooze, like accessing the url parameters. I don't have much experience with it but I recommend checking it out.

update june 2018: also don't miss the ongoing rewrite of Weblocks, it's going to be huge ! :D http://40ants.com/weblocks/quickstart.html Weblocks allows to build dynamic webapps, without a line of Javascript, without separating the back and front. It is components-based, like React but server-side. It's very alpha as of writing (june 2018), but in progress, and it's working, I have a couple simple web apps working.

A simple way of get the request parameters (something like: get-get #key, get-post #key, get-cookie #key).

I found easier the Lucerne way, it iss as simple as a with-params macro (real world example):

@route app (:post "/tweet")
(defview tweet ()
  (if (lucerne-auth:logged-in-p)
      (let ((user (current-user)))
        (with-params (tweet)
          (utweet.models:tweet user tweet))
        (redirect "/"))
      (render-template (+index+)
                       :error "You are not logged in.")))

Caveman's way has been less clear to me.

Mysql access

Caveman advertises database integration (with Fukamachi's Datafly and sxql).

You can just use clsql or the Mito ORM: https://lispcookbook.github.io/cl-cookbook/databases.html

HTML Form generators, processing, validators, etc.

I don't know if there are form generators out there. edit: there are: cl-forms and formlets, or again 1forms, working with Caveman2.

Caveman does not have one (issue raised in 2011).

Helpers for filter user input data (something like htmlentities, escape variables for put in queries, etc).

Ratify is an input validation library, not integrated into a framework though.

FLOSS and GNU/Linux friendly ✓

Other web stuff

Speaking about web, there are other nice libraries in CL land:

• web servers: Woo is a fast HTTP server, faster than Nodejs (beware of charts…), wookie is an async http server,
• Dexador is an HTTP client
• Plump, lquery and CLSS make it easy to parse html and query the DOM.
• cl-bootstrap offers twitter-bootstrap shortcuts for the cl-who templating engine (which kind of replaces Jade/Pug, even though we have usual templates too).

Ajax in Lisp

(remember, with Weblocks, see above, we might not need those)

• Wuwei is an interesting experiment that enables to write Ajax views in Common Lisp. The website has nice real-world demos. It can include other Javascript libraries.
• also SmackJack, explained in this recent blog post (2017).

Answer 4

You can do web development with guile scheme. Its standard library includes the (sxml simple) module that is very useful for html generation, manipulation, and parsing. The guile-www library adds support for http, cgi, etc. The guile-dbi library provides access to MySQL and other databases. With these building blocks, you can implement everything from simple cgi scripts to web applications with their own HTTP server.

Answer 5

I've written a pretty extensive tutorial/ebook on the topic: http://lispwebtales.ppenev.com/

Quick summary:

• It uses Common Lisp
• It uses the Restas framework
• It has examples for pretty much most of basic web development, including DB access, authentication, HTML generation and templating.
• Since the Restas documentation is pretty much out of date, my tutorial is the closest thing to up to date docs.
• Shows a few of the more advanced features, like policies, which allow you to write pluggable interfaces, for instance you can write a data store layer, and write back-ends for different storage mechanisms with relative ease, the module system which allows you to write reusable components, like auth frameworks and things like that.
• It covers things like installing lisp, setting up the ASDF build system and the quicklisp package manager etc.
• It's free online, and as soon as I finish it it will be free on leanpub as well. The source is on https://github.com/pvlpenev/lispwebtales under a CC license, the source code is MIT. Not all of it is published yet, and I'm in the process of revising.

Answer 6

Paul Graham (and friends) made a lisp dialect specifically for writing basic web applications. It's called Arc, and you can get it at arclanguage.org.

It's probably not suited for really big complex websites and I'm not sure what state it's database support is at but Paul Graham knows how to write web applications in lisp, so Arc will make the HTTP/HTML part easy for you while you spend most of your brain cycles learning the lisp way.