old_contents: var jws = require('jws');
  
  module.exports.decode = function (jwt) {
    var decoded = jws.decode(jwt, {json: true});
    return decoded && decoded.payload;
  };
  
  module.exports.sign = function(payload, secretOrPrivateKey, options) {
    options = options || {};
  
    var header = {typ: 'JWT', alg: options.algorithm || 'HS256'};
  
    payload.iat = Math.floor(Date.now() / 1000);
  
    if (options.expiresInMinutes) {
      var ms = options.expiresInMinutes * 60;
      payload.exp = payload.iat + ms;
    }
  
    if (options.audience)
      payload.aud = options.audience;
  
    if (options.issuer)
      payload.iss = options.issuer;
  
    if (options.subject)
      payload.sub = options.subject;
  
    var signed = jws.sign({header: header, payload: payload, secret: secretOrPrivateKey});
  
    return signed;
  };
  
  module.exports.verify = function(jwtString, secretOrPublicKey, options, callback) {
    if ((typeof options === 'function') && !callback) callback = options;
    if (!options) options = {};
  
    if (!jwtString)
      return callback(new JsonWebTokenError('jwt must be provided'));
  
    var parts = jwtString.split('.');
    if (parts.length !== 3)
      return callback(new JsonWebTokenError('jwt malformed'));
  
    if (parts[2].trim() === '' && secretOrPublicKey)
      return callback(new JsonWebTokenError('jwt signature is required'));
  
    var valid;
    try {
      valid = jws.verify(jwtString, secretOrPublicKey);
    }
    catch (e) {
      return callback(e);
    }
  
    if (!valid)
      return callback(new JsonWebTokenError('invalid signature'));
  
    var payload;
  
    try {
     payload = this.decode(jwtString);
    } catch(err) {
      return callback(err);
    }
  
    if (payload.exp) {
      if (Math.floor(Date.now() / 1000) >= payload.exp)
        return callback(new TokenExpiredError('jwt expired', new Date(payload.exp * 1000)));
    }
  
    if (options.audience) {
      var audiences = Array.isArray(options.audience)? options.audience : [options.audience];
      if (audiences.indexOf(payload.aud) < 0)
        return callback(new JsonWebTokenError('jwt audience invalid. expected: ' + payload.aud));
    }
  
    if (options.issuer) {
      if (payload.iss !== options.issuer)
        return callback(new JsonWebTokenError('jwt issuer invalid. expected: ' + payload.iss));
    }
  
    callback(null, payload);
  };
  
  var JsonWebTokenError = module.exports.JsonWebTokenError = function (message, error) {
    Error.call(this, message);
    this.name = 'JsonWebTokenError';
    this.message = message;
    if (error) this.inner = error;
  };
  
  JsonWebTokenError.prototype = Object.create(Error.prototype);
  JsonWebTokenError.prototype.constructor = JsonWebTokenError;
  
  var TokenExpiredError = module.exports.TokenExpiredError = function (message, expiredAt) {
    JsonWebTokenError.call(this, message);
    this.name = 'TokenExpiredError';
    this.expiredAt = expiredAt;
  };
  TokenExpiredError.prototype = Object.create(JsonWebTokenError.prototype);
  TokenExpiredError.prototype.constructor = TokenExpiredError;
  
new_contents: var jws = require('jws');
  
  module.exports.decode = function (jwt) {
    var decoded = jws.decode(jwt, {json: true});
    return decoded && decoded.payload;
  };
  
  module.exports.sign = function(payload, secretOrPrivateKey, options) {
    options = options || {};
  
    var header = {typ: 'JWT', alg: options.algorithm || 'HS256'};
  
    if (!options.noTimestamp) {
      payload.iat = Math.floor(Date.now() / 1000);
    }
  
    if (options.expiresInMinutes) {
      var ms = options.expiresInMinutes * 60;
      payload.exp = payload.iat + ms;
    }
  
    if (options.audience)
      payload.aud = options.audience;
  
    if (options.issuer)
      payload.iss = options.issuer;
  
    if (options.subject)
      payload.sub = options.subject;
  
    var signed = jws.sign({header: header, payload: payload, secret: secretOrPrivateKey});
  
    return signed;
  };
  
  module.exports.verify = function(jwtString, secretOrPublicKey, options, callback) {
    if ((typeof options === 'function') && !callback) callback = options;
    if (!options) options = {};
  
    if (!jwtString)
      return callback(new JsonWebTokenError('jwt must be provided'));
  
    var parts = jwtString.split('.');
    if (parts.length !== 3)
      return callback(new JsonWebTokenError('jwt malformed'));
  
    if (parts[2].trim() === '' && secretOrPublicKey)
      return callback(new JsonWebTokenError('jwt signature is required'));
  
    var valid;
    try {
      valid = jws.verify(jwtString, secretOrPublicKey);
    }
    catch (e) {
      return callback(e);
    }
  
    if (!valid)
      return callback(new JsonWebTokenError('invalid signature'));
  
    var payload;
  
    try {
     payload = this.decode(jwtString);
    } catch(err) {
      return callback(err);
    }
  
    if (payload.exp) {
      if (Math.floor(Date.now() / 1000) >= payload.exp)
        return callback(new TokenExpiredError('jwt expired', new Date(payload.exp * 1000)));
    }
  
    if (options.audience) {
      var audiences = Array.isArray(options.audience)? options.audience : [options.audience];
      if (audiences.indexOf(payload.aud) < 0)
        return callback(new JsonWebTokenError('jwt audience invalid. expected: ' + payload.aud));
    }
  
    if (options.issuer) {
      if (payload.iss !== options.issuer)
        return callback(new JsonWebTokenError('jwt issuer invalid. expected: ' + payload.iss));
    }
  
    callback(null, payload);
  };
  
  var JsonWebTokenError = module.exports.JsonWebTokenError = function (message, error) {
    Error.call(this, message);
    this.name = 'JsonWebTokenError';
    this.message = message;
    if (error) this.inner = error;
  };
  
  JsonWebTokenError.prototype = Object.create(Error.prototype);
  JsonWebTokenError.prototype.constructor = JsonWebTokenError;
  
  var TokenExpiredError = module.exports.TokenExpiredError = function (message, expiredAt) {
    JsonWebTokenError.call(this, message);
    this.name = 'TokenExpiredError';
    this.expiredAt = expiredAt;
  };
  TokenExpiredError.prototype = Object.create(JsonWebTokenError.prototype);
  TokenExpiredError.prototype.constructor = TokenExpiredError;
  
subject: Allow noTimestamp option