streaming functional transformer for couchdb using node

couch-transform.js

var request = require('request').defaults({json: true}),
  transfuse = require('transfuse'),
  JSONStream = require('JSONStream');

function transform(couchdb, funcString, headers) {
  var down = request({url: couchdb + '/_all_docs?include_docs=true'}),
    up = request({url: couchdb + '/_bulk_docs', method: "POST", headers: headers}),
    tr = transfuse(['rows', /./, 'doc'], funcString, JSONStream.stringify("{\"docs\":[\n", "\n,\n", "\n]}\n"));
  down.pipe(tr)
  tr.pipe(up)
}

// transform('http://localhost:5984/cats', 'function(doc, map) { doc.type = "cat"; map(doc) }')