urembed

Ur/Web module generator: embed custom file or JavaScript code into your Ur/Web application

Monthly Downloads: 6

Programming language: Haskell

License: BSD 3-clause "New" or "Revised" License

Tags: Development     Ur/Web    

README

UrEmbed

Embeds file(s) into the Ur/Web project by creating the module containing

datatype content = File_A | File_B ...
val binary : content -> transaction blob

Additionally, Urembed greatly simplifies writing of the JavaScript FFIs.

Installation

You will need Haskell platform and several additional packages. Also, POSIX environment is required (Cygwin should suffice under Windows)

$ git clone https://github.com/grwlf/urembed
$ cd urembed
$ cabal configure
$ cabal build
$ cabal install

Usage

$ urembed --help
UrEmebed is the Ur/Web module generator

Usage: urembed [-o|--output FILE.urp] [--version] [FILE]

  Converts a set of FILEs into the Ur/Web modules. Each Module will contain
  following functions:

    val binary : unit -> transaction blob
    val blobpage : unit -> transaction page
    val text : unit -> transaction string

    Additionally, FFI signatures will be provided for JavaScript files. In order
    to enable this, you have to name your JS functions using the name__type
    scheme. See README for details. Also, uru project uses this a lot.

    (NOTE: the interface is not stable. Pleas, fork the Urembed sources
    before using)

  The master project (specified with -o FILE.urp) will contain a dictionary
  version of those functions taking the datatype key as an argument, instead of
  unit. In order to actually compile the binaries, you have to call

    make -f FILE.mk CC=.. LD=.. UR_INCLUDE_DIR=.. urp

  Where FILE.mk is the Makefile, generated by urembed.

    Example: urembed -o static/Static.urp Style.css Script.js
             make -C static -f Static.mk CC=gcc LD=ld UR_INCLUDE_DIR=/usr/local/include/urweb urp

  Note: output directory should exist


Available options:
  -h,--help                Show this help text
  -o,--output FILE.urp     Name of the Ur/Web project being generated
  --version                Show version information
  FILE                     File to embed

Example

To embed Style.css into ypur Ur/Web project:

1. Run urembed

   $ urembed -o lib/autogen/Static.urp Style.css
   
   Static.urp.in will be generated as well as Static.mk describing the rules
   to build all the binaries
   

2. Run make to build Static.urp

   $ make -C lib/autogen -f Static.mk urp
   

3. Include Static.urp into your master .urp file.

   # App.urp
   ...
   library lib/autogen/Static
   ...
   

4. Use the functionality. In this case, lets ship Style.css to the user

   # App.ur
   (* Direct call *)
   fun serve_css {} =
     b <- Static.binary Static.Style_css;
     returnBlob b (blessMime "text/css")
   
   (* Serve using a blobpage. Uremebed calls blessMime inside *)
   fun style2 {} = Static.blobpage Static.Style_css
   
   (* Serve directly, not using a dictionary *)
   fun style3 {} = Style_css.blobpage {}
   

JavaScript FFI helper

Urembed is able to bind top-level JavaScript functions via JavaScript FFI. In order to do it, user has to make sure that FILE has .js extension and contains top-level functions named according to the 'name__type' format. For example:

• Simple function

   # FILE.js
   function init__unit(menustyle__css_class, text__string) {}
  

  will be translated into Ur/Web's function

   # FILE.urs
   val init : css_class -> string -> transaction unit
  

• Also, it is allowed to drop the name__ part for argument names, so this is also legal

   # FILE.js
   function init__unit(css_class, string) {}
  

  results in

   # FILE.urs
   val init : css_class -> string -> transaction unit
  

• Next, the pure_ prefix in type name will instruct urembed to declare pure function (without 'transaction' part)

   # FILE.js
   function init__pure_string(css_class, string) {}
  

  results in

   # FILE.urs
   val init : css_class -> string -> string
  

• Finally, sometimes users want to declare their own types. Here is how to do it with Urembed:

   # FILE.js
  
   // Dummy javascript variable, just to set type name
   var type__tmce_imglist;
  
   function imglist_new__tmce_imglist( unit ) {
     return [];
   }
  
   function imglist_insert__tmce_imglist(string, url, tmce_imglist) {
     return tmce_imglist.concat([{title:string, value:url}]);
   }
  
   # FILE.urs
   type tmce_imglist
   val imglist_new : unit -> transaction tmce_imglist
   val imglist_insert : string -> url -> tmce_imglist -> transaction tmce_imglist