mongo_map_reduce.js

// calculate n reports per week

m = function() {
    var getWeek = function(d) {
        dowOffset = typeof(dowOffset) == 'int' ? dowOffset : 1;
        var newYear = new Date(d.getFullYear(),0,1);
        var day = newYear.getDay() - dowOffset;
        day = (day >= 0 ? day : day + 7);
        var daynum = Math.floor((d.getTime() - newYear.getTime() - (d.getTimezoneOffset()-newYear.getTimezoneOffset())*60000)/86400000) + 1;
        var weeknum;
        if (day < 4) {
            weeknum = Math.floor((daynum+day-1)/7) + 1;
            if(weeknum > 52) {
                nYear = new Date(d.getFullYear() + 1,0,1);
                nday = nYear.getDay() - dowOffset;
                nday = nday >= 0 ? nday : nday + 7;
                weeknum = nday < 4 ? 1 : 53;
            }
        } else {
            weeknum = Math.floor((daynum+day-1)/7);
        }
        return weeknum;
    };
    var data = {serviceref: this.metadata.serviceref, count: 1};
    emit(getWeek(this.metadata.publishdate), 1);
};

r = function(previous, current){
    var sum = 0;
    for (index in current) {
        sum += current[index];
    }
    return sum;
};

use publications
res = db.reports.files.mapReduce(m, r, {query: {'metadata.publishdate': {$gte: new Date(2010, 00, 01), $lte:new Date(2010, 05, 01)}}})
db[res.result].find()