gulp-rev-suffix/index.js

Cache-busting plugin(new support for custom rev-type compared with gulp-rev-append) for gulp.

var fs = require('fs');
var path = require('path');
var crypto = require('crypto');
var Buffer = require('buffer').Buffer;
var gutil = require('gulp-util');
var PluginError = gutil.PluginError;
var map = require('event-stream').map;

var FILE_DECL = /(?:href=|src=|url\()['|"]([^\s>"']+?)\?rev=@@([^\s>"']+?)['|"]/gi;

//add custom rev-types
/*
var revType=[{
  type:'timestamp',  //custom type name and declared in html files defined using the following suffix 'rev=@@type-name'
  value:function () { //func to return the type value
    return Date.now();
  }
}];
*/
var revPlugin = function revPlugin(revTypes) {

  return map(function(file, cb) {

    var contents;
    var lines;
    var i, length;
    var line;
    var groups;
    var declarations;
    var dependencyPath;
    var data, hash;

    if(!file) {
      throw new PluginError('gulp-rev-suffix', 'Missing file option for gulp-rev-suffix.');
    }

    if(!file.contents) {
      throw new PluginError('gulp-rev-suffix', 'Missing file.contents required for modifying files using gulp-rev-suffix.');
    }

    contents = file.contents.toString();
    lines = contents.split('\n');
    length = lines.length;

    for(i = 0; i < length; i++) {
      line = lines[i];
      declarations = line.match(FILE_DECL);
      if (declarations && declarations.length > 0) {
        for(var j = 0; j < declarations.length; j++) {
          groups = FILE_DECL.exec(declarations[j]);
          if(groups && groups.length > 1) {
            // are we an "absoulte path"? (e.g. /js/app.js)
            var normPath = path.normalize(groups[1]);
            if (normPath.indexOf(path.sep) === 0) {
              dependencyPath = path.join(file.base, normPath);
            }
            else {
              dependencyPath = path.resolve(path.dirname(file.path), normPath);
            }
            try {
              var rev='';
              if(revTypes && revTypes.length>0){
                for(var revTypeIndex in revTypes){
                  var revType=revTypes[revTypeIndex];
                  if(revType.type===groups[2]){
                    if(typeof revType.value==='function') rev=revType.value();
                    break;
                  }
                }
              }
              if(!rev){
                data = fs.readFileSync(dependencyPath);
                hash = crypto.createHash('md5');
                hash.update(data.toString(), 'utf8');
                rev=hash.digest('hex');
              }
              line = line.replace('@@'+groups[2], rev);
            }
            catch(e) {
              // fail silently.
            }
          }
          FILE_DECL.lastIndex = 0;
        }
        lines[i] = line;
      }
    }

    file.contents = new Buffer(lines.join('\n'));
    cb(null, file);

  });

};

module.exports = revPlugin;