Posts Tagged ‘clojure’

Clojure-refactoring gets a little love, a new release and a new maintainer.

Monday, October 24th, 2011

clojure-refactoring, the Emacs/SLIME based toolkit for doing refactoring wasn’t getting enough love and attention, so I fixed a few things. Tom Crayford unfortunately doesn’t have the time to work on it any further so I’m taking over as the maintainer. Inspect the code at the new “official” repository.

For now, I’m focused on fixing parsing issues first, then installing ease (I’m thinking about packaging everything Emacs-related on marmalade but that depends on what’s the easiest way to get stuff integrated for the user on the Emacs and Clojure sides). I’ve already removed the dependencies on out-dated libraries. Basically, everything I need to make the current functionality reliable enough for production use. Next up is support for clojure 1.3, probably, if that needs any work (I’m running 1.2 in production everywhere for now).

For the further future, I’d like this code to be useful for other editors/APIs/tools, so the SLIME/swank/Emacs specific stuff probably has to be separated out at some point. Some more refactorings will also be useful.

For now, version 0.6.1 is on clojars. Get it while it’s hot.

Announcement: clj-authsub – AuthSub client in clojure

Saturday, October 8th, 2011

AuthSub is the authorization API Google uses for many of its products, meaning you can use it to ask a user to provide access to their private youtube listings, calendar entries etc without forcing them to hand over their password. The protocol is actually pretty simple and implementing it using clj-http was straight forward, except for one thing: clj-http always puts the connection port number in the Host header (which by the way is completely valid according to the HTTP/1.1 spec), but some google applications (notably, youtube) do not like that, giving a crypic HTTP status 401 “AuthSub token has the wrong scope” error. Figuring out the problem took a couple of hours given that that idiosyncrasy is not documented anywhere and I had to figure it out from some comments in the Python client for AuthSub.

With that issue out of the way, I’ve released clj-authsub version 0.1.0. It’s minimal and currently doesn’t support signed/secure tokens, but it works.

Announcement: pretzel – clojure predicate functions

Tuesday, April 5th, 2011

I’m working on pretzel right now. It’s a basic library that can be used to combine predicates and also holds a bunch of tests on string content.

Code and documentation is on github.

Announcement: flutter-decline-demo – validation and form generation on compojure

Saturday, April 2nd, 2011

Some people indicated they wanted some example code for my clj-decline
(validation) and flutter (form generation) libraries. So today I wrote
a simple demo application that uses both.

Get the code at github.

Announcement: flutter – clojure / hiccup form fields

Saturday, March 26th, 2011

I’ve been working on flutter, a library for saner form generation today. First (pretty basic) release was done on clojars. Still working on many details, including more-or-less full-coverage tests.

Get the code on github.

Also see the announcement on the clojure group.

Announcement: ring-persistent-cookies

Saturday, March 12th, 2011

Just released a minimal library to generate persistent cookies for ring.middleware.cookies.

It’s at github and clojars.org.

Announcement: clj-decline – validation sucks.

Saturday, March 12th, 2011

I pushed a new validation library for clojure to github yesterday. Check out clj-decline.

Why another validation library?

Well, why does validation suck so much?

Of course, dealing with user input is annoying anyway. But validation libraries always seem to want to do things in just the wrong way for the project you’re working on.

Let me count the ways:

  • They do too much. Session management? XSS detection? Javascript validation? Form definitions? Bollocks. It will never work with the code I’ve already got running in production and I’m not going to drag in all of it just to get the core validation functions, assuming I can even use them in my app.
  • Also, validation does not mean “force this input into another type”. That’s not validation. Stick it somewhere else.
  • They assume too much. If you can only validate a single value in a map, you’re useless. I need to check if a frobniz has either two wheebles or an odd number of crinks, and don’t try to stop me.
  • I might need to validate something that isn’t a map. Maybe I want to check two maps. Maybe I need to check a single string or a file upload.
  • They still assume too much. This may come as a shock, but not everyone speaks English on this planet. I have to support multiple languages in the same web app. Give me more options than pre-defined strings for errors, you lousy piece of American imperialist software! People of the earth, throw off your shackles and your “reality” TV shows!

    Ahem.

  • Macros, macros, macros all over the place. Yes, macros are cool, but no, I don’t want to stick every validation in a named var. If I wanted that, I could (def some-name (make-validation …)) so I don’t need your macro anyway. I want to use closures that validate for this specific user and now you’ve stopped me.
  • Don’t be passive agressive. Validation is a user-centric feature. If I wanted to tell the user only their first error, I’d use exceptions. Don’t force the user to submit their form twenty times until they’ve fixed all their mistakes. Give them as much information as possible so they know what’s going on.

    So, how does clj-decline fix all that?

    It doesn’t. It just stays away from most of the above. clj-decline is simple. It validates arguments and returns errors. Everything else is up to the user or some other library. It’s completely functional, has no macros, no built-in predicates, nothing binds it to a web framework or anything else, and errors / messages can be anything you like. The only decision I made is that errors are grouped by key (which can also be anything you like).

    Enjoy!

    Joost.

Talk @ amsterdam-clojurians, Wednesday March 9, 2011

Monday, March 7th, 2011

 ____________________ 
< Functional Clojure >
 -------------------- 
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

I’ll be doing a short presentation on the basic higher-order (sequence) functions in clojure.core at the Amsterdam Clojurians meeting next Wednesday. This talk should be understandable and useful for Clojure newbies. If you’re interested, just show up around 7.

Update: quite a few people showed up to the meeting. I’ve put the slides on github, and here is the elisp code I used to present the slides.

Announcement: ring-upload-progress

Saturday, September 18th, 2010

I’ve forked off ring.middleware.multipart-params into a new library called ring.middleware.upload-progress

It’s a bit rough-and-ready for now, and it uses the session to store the shared state about current uploads, which is probably not the best way to go about it – I’m thinking about introducing a new lower-level mechanism for low-memory shared state based on clojure’s STM tools, since this kind of thing is interesting for more than just uploads – but it does work as long as you’re not doing anything too fancy (if you’re worried, you can use a separate session store just for this info).

For the interested: the code is at github.

I’ve got some working “upload progress bar” javascript and routing code too, but it’s not in this project, so for now, you’ll have to roll your own.

I’ll get a clojars release done as soon as I’m satisfied this stuff is usable. Probably in the next few days.

Announcement: clj-sql and clj-imajine

Wednesday, September 15th, 2010

I just released a few bits of image code that might be useful to more people. clj-imajine can read, write and scale images. There’s also some minimal experimental pdf support. More features will be added when I need them or if someone else sends me a good pull request.

Source code is on github. Leiningen/maven jars are on clojars.

Also, Saul Hazledine got in touch with me to merge our changes of clojure.contrib.sql and make it an official project. It’s called clj-sql and differs from clojure.contrib.sql mostly in that it makes it possible to use :keywords-with-dashes as column names (for most operations, at least, so far) and that its support for auto-generated keys is much better, i.e. there is some!

Source code is on github. Leiningen/maven jars are on clojars.