oauth - Delphi TOAuth1Authenticator how to set the Realm

Question

Trying to use/call a NetSuite Restlet with token based authentication using the Delphi RESTClient. I have a working Postman request that verifies all the authorization parameters required. The one parameter missing - realm - when added in code does change the error message returned from the NetSuite side but still doesn't result in a successful call.

procedure TForm1.OAuth1Authenticator1Authenticate(ARequest: TCustomRESTRequest;
    var ADone: Boolean);
begin
  // XXXXXXX_RP is a NetSuite account number and environment 
  ARequest.AddAuthParameter('realm','XXXXXX_RP',pkQUERY);  
end;

If realm is not added (the above code is commented out) the returned rest content is:

error code: USER_ERROR
error message: header is not NLAuth scheme [ OAuth oauth_consumer_key="fe8da7b31dccbd47e90e5dd5e641fe7b0cbff032a951b4058618c207caf569f8", oauth_nonce="c98fa9de2c601f45bdc8d5c640f1b3cf", oauth_signature_method="HMAC-SHA1", oauth_signature="PfCQE3A4DicTtCfpBEPmbSOmqNg%3D", oauth_timestamp="1568639138", oauth_token="a8190ba34e223f25b32cdb4837d9e1973b8fd6208804e93306f4618ccdb6d648", oauth_version="1.0" ]

With realm added I still get:

error code: INVALID_LOGIN_ATTEMPT
error message: Invalid login attempt.

Anybody successfully make calls to NetSuite restlets using the Delphi RESTClient?

Update: Looks like it does not support using the optional realm parameter. Adding it manually gets it added to the normalized parameter list for signing when it shouldn't be. I have modified TOAuth1SignatureMethod_HMAC_SHA1.BuildSignature in REST.Authenticator.OAuth to skip this parameter (just added a if Lparam.Name <> 'realm' then begin .. end; block around some code) but still no luck successfully making a request to NetSuite. Did this after reading https://oauth.net/core/1.0/ section 9.1.1. Normalize Request Parameters:

The request parameters are collected, sorted and concatenated into a normalized string:

• Parameters in the OAuth HTTP Authorization header excluding the realm parameter.
• Parameters in the HTTP POST request body (with a content-type of application/x-www-form-urlencoded).
• HTTP GET parameters added to the URLs in the query part (as defined by [RFC3986] section 3).

Answer 1

Ended up manually assembling the request with Indy. A copy of the part that assembles the AUTH header is below along with code that does a test request using Indy's IdHTTP. Note: the Netsuite account number and IDs/Secrets are just for show.

procedure TForm1.Button1Click(Sender: TObject);
Const
  NETSUITE_ACCOUNT_ID = '4000000_RP';
  BASE_URL = 'https://4000000-rp.restlets.api.netsuite.com/app/site/hosting/restlet.nl';
  HTTP_METHOD = 'POST';
  SCRIPT_ID = '331';
  SCRIPT_DEPLOYMENT_ID = 'customdeploy_salesorderimport';
  OAUTH_VERSION = '1.0';
  TOKEN_ID = 'a8190ba34e223f25b3267843437d9e1973b8fd6208804e93306f4618ccdb6d648';
  TOKEN_SECRET = 'ecb5321eaf832714828ede7f920320b942ad6b2d4221da3b12496f389d68e1c4';
  CONSUMER_KEY = 'fe8da7c2cbd47e90e5dd5e6415fe7b0cbff2032a5951b4058618c07c7af569f8';
  CONSUMER_SECRET = '848cae6150a651ecbc6975656f4b92ca08d7c27c829185cf98e7a0a30c24dbc2';
Var
  OAUTH_NONCE,TIME_STAMP,STRING2SIGN : string;
  oauth_signature, oauth, BaseURL : string;
  JSONValue : TJsonValue;
begin
  OAUTH_NONCE :=  THashMD5.GetHashString(IntToStr(DateTimeToUnix(TTimeZone.Local.ToUniversalTime(Now))) + IntToStr(Random(MAXINT)));
  TIME_STAMP := IntToStr(DateTimeToUnix(TTimeZone.Local.ToUniversalTime(Now)));

  // These are in alphabetical order - required by signing
  STRING2SIGN := '';
  STRING2SIGN := STRING2SIGN + 'deploy=' + SCRIPT_DEPLOYMENT_ID + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_consumer_key=' + CONSUMER_KEY + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_nonce=' + OAUTH_NONCE + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_signature_method=' + 'HMAC-SHA256' + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_timestamp=' + TIME_STAMP + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_token=' + TOKEN_ID + '&';
  STRING2SIGN := STRING2SIGN + 'oauth_version=' + OAUTH_VERSION + '&';
  STRING2SIGN := STRING2SIGN + 'script=' + SCRIPT_ID;
  STRING2SIGN := URIEncode(STRING2SIGN);
  STRING2SIGN := HTTP_METHOD + '&' + URIEncode(BASE_URL) + '&' + STRING2SIGN;
  oauth_signature := URIEncode(TNetEncoding.Base64.EncodeBytesToString(THashSHA2.GetHMACAsBytes(STRING2SIGN, CONSUMER_SECRET + '&' + TOKEN_SECRET)));

  oauth :='OAuth oauth_signature="' + oauth_signature + '",';
  oauth := oauth + 'oauth_version="' + OAUTH_VERSION + '",';
  oauth := oauth + 'oauth_nonce="' + OAUTH_NONCE + '",';
  oauth := oauth + 'oauth_signature_method="HMAC-SHA256",';
  oauth := oauth + 'oauth_consumer_key="' + CONSUMER_KEY + '",';
  oauth := oauth + 'oauth_token="' + TOKEN_ID + '",';
  oauth := oauth + 'oauth_timestamp="' + TIME_STAMP + '",';
  oauth := oauth + 'realm="' + NETSUITE_ACCOUNT_ID + '"';

  BaseURL := BASE_URL + '?script=' + SCRIPT_ID + '&deploy=' + SCRIPT_DEPLOYMENT_ID;

  IdHTTP1.Request.CustomHeaders.FoldLines := false;
  IdHTTP1.Request.Accept := 'application/json, text/javascript, */*; q=0.01';
  IdHTTP1.Request.ContentType := 'application/json';
  IdHTTP1.Request.CustomHeaders.Values['Authorization'] := oauth;
try
  memo1.Text := idhttp1.Post(BaseURL,'C:UsersevansDocumentsJson.txt');
  JSONValue :=  TJSonObject.ParseJSONValue(memo1.Text);
  SynEdit1.Text := JSonValue.Format;
finally
  JSonValue.Free;
end;

Note: code updated to use SHA256 instead of SHA1 for OAUTH signing. NetSuite has sent out notice they will be requiring this with NetSuite Release 2021.2.