mongorc.js

// generate a MONGO_PS1 DB_STATE#host[dbname]>
(function() {
  'use strict';
  var states = ['STARTUP', 'PRIMARY', 'SECONDARY', 'RECOVERING', 'FATAL', 'STARTUP2', 'UNKNOWN', 'ARBITER', 'DOWN', 'ROLLBACK'];
  var host = typeof db === 'undefined' ? '' : db.serverStatus().host;

  prompt = function() {
    if (typeof db === 'undefined') {
      return '> ';
    }

    var dbState;
    var status = '';
    var dbStatus = db.isMaster();

    if (dbStatus.setName) {
      if (dbStatus.ismaster) {
        dbState = 'PRIMARY';
      } else if (dbStatus.secondary) {
        dbState = 'SECONDARY';
      } else {
        dbState = states[rs.status().myState];
      }
      if (dbStatus.hidden) {
        dbState = dbState.toLowerCase();
      }
      status = dbState + ':[' + dbStatus.setName + ']#';
    }
    return status + host + ' [' + db + ']> ';
  };
})();

// always enable pretty print
DBQuery.prototype._prettyShell = true;