lib/api.js
function(identifier, revisionIdentifier, target, cb) {
    logger.info('get revision: ' + identifier + ', ' + revisionIdentifier);
    var systemId = _sr.findSystem(identifier);
    if (!systemId) { logger.error(ERR_NOSYSID); return cb(new Error(ERR_NOSYSID)); }
    fetchTarget(systemId, target, revisionIdentifier, function(err, target) {
      if (err) { return cb(err); }
      _sr.findRevision(systemId, revisionIdentifier, function(err, revisionId) {
        if (err) { return cb(err); }
        _sr.getRevision(systemId, revisionId, target, cb);
      });
    });
  }
function(identifier, revisionIdentifier, target, cb) {
    logger.info('get revision: ' + identifier + ', ' + revisionIdentifier);
    var systemId = _sr.findSystem(identifier);
    if (!systemId) { logger.error(ERR_NOSYSID); return cb(new Error(ERR_NOSYSID)); }
    fetchTarget(systemId, target, revisionIdentifier, function(err, target) {
      if (err) { return cb(err); }
      _sr.findRevision(systemId, revisionIdentifier, function(err, revisionId) {
        if (err) { return cb(err); }
        _sr.getRevision(systemId, revisionId, target, cb);
      });
    });
  }
get a specific revision