riakselect.js

/*
  Uses http://jsonselect.org/ to select fields from a riak object
 */
function map_jsonselect(values, keydata, arg) {
  var data = Riak.mapValuesJson(values)[0];

  if(typeof arg == "string") {
    return JSONSelect.match(arg, data);
  } else if(typeof arg == "object") {
    var accum = {}
    for(key in arg) {
      var result = JSONSelect.match(arg[key], data);
      if(result.length == 1) {
        accum[key] = result[0];
      } else {
        accum[key] = result;
      }
    }
    return [accum];
  }
}

test.json

{"inputs": [ ["goog", "2005-05-04"], ["goog", "2005-05-05"]],
 "query": [
   {"map": {"language": "javascript", "name": "map_jsonselect", "arg": {"high": ".High", "low": ".Low"}}},
   {"reduce": {"language": "javascript", "source": "function(v) { return v; }"}}
 ]}