there is a way by which we parse any time input given by user...
here i am taking the input of a connection string from a text file
i am supposed to assume that the user who keeps this string in the text file can be trusted.
but what if he makes a typo a mistake unknowingly, that will cause the coming code to cause exception,
i would like a way to check the string for the correct format, like parse it some way to see if it is the way an connection tring should be, and then possibly use that parsed result.
edit
as requested the sample code i using, and the connection the sqladaptor using
//Connect to a remote instance of SQL Server.
Server srv;
ServerConnection conContext = new ServerConnection();
conContext.ServerInstance = #"A-63A9D4D7E7934\SECOND";
conContext.LoginSecure = false;
conContext.Login = "sa";
conContext.Password = "two";
srv = new Server(conContext);
Response.Write(srv.Information.Version);
//Data Source=A-63A9D4D7E7834\SECOND;Initial Catalog=replicate;User ID=sa;Password=***********
A regular expresion can't validate an incorrect password, user name, or host name, so it is possible for your user to generate a valid string that will still cause an exception.
Also, you can't build a regex that will cover every possible combination of connection arguments.
The only robust solution, would be to wrap the connection code in a try/catch block and provide an appropriate error message.
Related
What is the recommended way to convert a raw String, with one FIX message, to one QuickFIX/J Message object of the appropriate type, like one quickfix.fix44.ExecutionReport object?
I only have to deal with the FIX 4.4 version.
I found two options at this thread on Quickfixj-users mailing list.
I adapted these options to my situation and I was able to convert the message successfully in two different ways.
Example of a FIX message:
8=FIX.4.49=11035=834=749=EXEC52=20211014-19:39:25.75856=BANZAI6=011=114=10017=137=139=154=155=IBM150=2151=40010=237
I'd like to know which of the options below is better or if both are wrong and there's a better way.
Thanks in advance.
1 Option
quickfix.Message rawMessage = new quickfix.Message(rawMessageString);
// Example of MsgType = 8
MsgType msgType = new MsgType();
rawMessage.getHeader().getField(msgType);
MessageFactory messageFactory = new DefaultMessageFactory(ApplVerID.FIX44);
quickfix.Message message = messageFactory.create("FIX.4.4", msgType.getValue());
message.fromString(messageString, null, false, true);
// message.getName() = quickfix.fix44.ExecutionReport
System.out.println(message.getName() = " + message.getClass().getName());
2 Option
MessageFactory messageFactory = new DefaultMessageFactory(ApplVerID.FIX44);
quickfix.Message messageFromMessageUtils = quickfix.MessageUtils.parse(messageFactory, null, rawMessageString);
// message.getName() = quickfix.fix44.ExecutionReport
System.out.println(message.getName() = " + message.getClass().getName());
Data Dictionary
In the above tests, I didn't use a Data Dictionary, but in my real application I'll use one.
What I especially dislike about option 1 is that you need to construct two messages. One for the extraction of the MsgType and afterwards the actual message. Seems unnecessary to me.
If you are only using FIX4.4 I would go for the second option because it does all the magic for you, i.e. extracts the needed things like BeginString and MsgType from the raw String.
Downside: it will only work up to and including FIX4.4 since MessageUtils.parse() does only consider the BeginString (not the ApplVerID).
However, this should be no problem for your use case.
P.S.: If you ever need to parse messages for FIX5.0 and upwards, use the following (which is basically option 1 but without constructing a message to get the MsgType):
String msgType = MessageUtils.getMessageType(rawMessageString);
MessageFactory messageFactory = new DefaultMessageFactory(ApplVerID.FIX50); // FIX5.0 for example
quickfix.Message message = messageFactory.create("FIXT.1.1", ApplVerID.FIX50, msgType);
message.fromString(rawMessageString, dd, false, true);
P.P.S.: Not of interest for your use case but for the sake of completeness: you could also use one of the quickfix.Message(String) constructors but that would not return you a message of the correct type. Just a general quickfix.Message.
I want to use the can_msgs/Frame.msg for decoding can messages using db.decode_message(Frame.id, Frame.data) but it is giving error
I want to try and write a new Frame.msg format but will it help?
def callback(Frame):
rospy.loginfo(rospy.get_caller_id() + "I heard %s", Frame.data)
Temp = db.decode_message(Frame.id, Frame.data)
temp.data = Temp
pub.publish(temp)
I want to print the message in the dbc format that the cantools package helps decoding.
Error:
File "safa.py", line 42, in callback
temp = db.decode_message(Frame.id, Frame.data)
File "build/bdist.linux-x86_64/egg/cantools/database/can/database.py", line 379, in decode_message
message = self._name_to_message[frame_id_or_name]
KeyError: 10
Looking at the cantools documentation for db.decode_message, the KeyError is a bad description/error msg for the following.
db is a database (class cantools.database.can.Database), which stores all the weird encodings we may choose to use with cantools. To decode a message, it must already have an encoding stored within it, using one of the db.add_* methods with the class.
Edit:
The definition of the can_msgs/Frame is
std_msgs/Header header
uint32 id
bool is_rtr
bool is_extended
bool is_error
uint8 dlc
uint8[8] data
The data term requires an array/list of 8 uint8 values, not a string. Any CANbus data encoding must finish in this form.
Additionally, ROS provides an interface to the CANbus already: socketcan_bridge can be called in a launch file with your node at the same time.
Before you can decode messages you should setup the database e.g by loading a dbc file:
try:
dbc_file_object = open(dbc_file, 'r')
except IOError as e:
rospy.loginfo('Unable to open file {}'.format(e))
sys.exit(-1)
self.db = cantools.db.load(dbc_file_object)
CONCLUSION:
For some reason the flow wouldn't let me convert the incoming message to a BLOB by changing the Message Domain property of the Input Node so I added a Reset Content Descriptor node before the Compute Node with the code from the accepted answer. On the line that parses the XML and creates the XMLNSC Child for the message I was getting a 'CHARACTER:Invalid wire format received' error so I took that line out and added another Reset Content Descriptor node after the Compute Node instead. Now it parses and replaces the Unicode characters with spaces. So now it doesn't crash.
Here is the code for the added Compute Node:
CREATE FUNCTION Main() RETURNS BOOLEAN
BEGIN
DECLARE NonPrintable BLOB X'0001020304050607080B0C0E0F101112131415161718191A1B1C1D1E1F7F808182838485868788898A8B8C8D8E8F909192939495969798999A9B9C9D9E9FA0A1A2A3A4A5A6A7A8A9AAABACADAEAFB0B1B2B3B4B5B6B7B8B9BABBBCBDBEBFC0C1C2C3C4C5C6C7C8C9CACBCCCDCECFD0D1D2D3D4D5D6D7D8D9DADBDCDDDEDFE0E1E2E3E4E5E6E7E8E9EAEBECEDEEEFF1F2F3F4F5F6F7F8F9FAFBFCFDFEFF';
DECLARE Printable BLOB X'20202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020202020';
DECLARE Fixed BLOB TRANSLATE(InputRoot.BLOB.BLOB, NonPrintable, Printable);
SET OutputRoot = InputRoot;
SET OutputRoot.BLOB.BLOB = Fixed;
RETURN TRUE;
END;
UPDATE:
The message is being parsed as XML using XMLNSC. Thought that would cause a problem, but it does not appear to be.
Now I'm using PHP. I've created a node to plug into the legacy flow. Here's the relevant code:
class fixIncompetence {
function evaluate ($output_assembly,$input_assembly) {
$output_assembly->MRM = $input_assembly->MRM;
$output_assembly->MQMD = $input_assembly->MQMD;
$tmp = htmlentities($input_assembly->MRM->VALUE_TO_FIX, ENT_HTML5|ENT_SUBSTITUTE,'UTF-8');
if (!empty($tmp)) {
$output_assembly->MRM->VALUE_TO_FIX = $tmp;
}
// Ensure there are no null MRM fields. MessageBroker is strict.
foreach ($output_assembly->MRM as $key => $val) {
if (empty($val)) {
$output_assembly->MRM->$key = '';
}
}
}
}
Right now I'm getting a vague error about read only messages, but before that it wasn't working either.
Original Question:
For some reason I am unable to impress upon the senders of our MQ
messages that smart quotes, endashes, emdashes, and such crash our XML
parser.
I managed to make a working solution with SQL queries, but it wasted
too many resources. Here's the last thing I tried, but it didn't work
either:
CREATE FUNCTION CLEAN(IN STR CHAR) RETURNS CHAR BEGIN
SET STR = REPLACE('–',STR,'–');
SET STR = REPLACE('—',STR,'—');
SET STR = REPLACE('·',STR,'·');
SET STR = REPLACE('“',STR,'“');
SET STR = REPLACE('”',STR,'”');
SET STR = REPLACE('‘',STR,'&lsqo;');
SET STR = REPLACE('’',STR,'’');
SET STR = REPLACE('•',STR,'•');
SET STR = REPLACE('°',STR,'°');
RETURN STR;
END;
As you can see I'm not very good at this. I have tried reading about
various ESQL string functions without much success.
So in ESQL you can use the TRANSLATE function.
The following is a snippet I use to clean up a BLOB containing non-ASCII low hex values so that it then be cast into a usable character string.
You should be able to modify it to change your undesired characters into something more benign. Basically each hex value in NonPrintable gets translated into its positional equivalent in Printable, in this case always a full-stop i.e. x'2E' in ASCII. You'll need to make your BLOB's long enough to cover the desired range of hex values.
DECLARE NonPrintable BLOB X'000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F202122232425262728292A2B2C2D2E2F303132333435363738393A3B3C3D3E3F';
DECLARE Printable BLOB X'2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E2E';
SET WorkBlob = TRANSLATE(WorkBlob, NonPrintable, Printable);
BTW if messages with invalid characters only come in every now and then I'd probably specify BLOB on the input node and then use something similar to the following to invoke the XMLNSC parser.
CREATE LASTCHILD OF OutputRoot DOMAIN 'XMLNSC'
PARSE(InputRoot.BLOB.BLOB CCSID InputRoot.Properties.CodedCharSetId ENCODING InputRoot.Properties.Encoding);
With the exception terminal wired up you can then correct the BLOB's of any messages containing parser breaking invalid characters before attempting to reparse.
Finally my best wishes as I've had a number of battles over the years with being forced to correct invalid message content in the "Integration Layer" after all that's what it's meant to do.
I am new to C# and QBFC13 code and I'm trying to add a bill from code I found on the intuit developer site under the BillAdd section.
The BillAddRq.ExternalGUID.SetValue(Guid.NewGuid().ToString()); is throwing a error:
Invalid GUID format. Must use zero for Custom Fields, or a GUID generated with GuidGen.exe for private data extensions.
I’ve tried:
String guid = System.Guid.NewGuid().ToString("B");
// MessageBox to see that it creates the number
MessageBox.Show("guid", guid);
BillAddRq.ExternalGUID.SetValue(guid);
BillAddRq.ExternalGUID.SetValue(Guid.NewGuid().ToString("B"));
And
String guid = System.Guid.NewGuid().ToString("0");
And those throw:
QB Test 8-14-2014.vshost.exe - No Disk "There is no disk in the drive. Please insert a disk into drive F."
How can I resolve these errors?
Using your first string attempt is the correct format for the GUID. I tested using GUID.NewGuid().ToString("B") and was able to get a GUID that works when adding a bill.
Because you're getting an error about there being no disk in the drive, it sounds like something else is causing the error. I would step through the code and find the exact place that causes the error as it probably has nothing to do with the GUID.
Here's a simple example that I did using a sample file in QuickBooks:
QBSessionManager SessionManager = new QBSessionManager();
SessionManager.OpenConnection2("GUIDTest","GUIDTest", ENConnectionType.ctLocalQBD);
SessionManager.BeginSession("", ENOpenMode.omDontCare);
IMsgSetRequest MsgRequest = sessionManager.CreateMsgSetRequest("US", 13, 0);
MsgRequest.Attributes.OnError = ENRqOnError.roeContinue;
IBillAdd add = MsgRequest.AppendBillAddRq();
add.ExternalGUID.SetValue(System.Guid.NewGuid().ToString("B"));
add.VendorRef.FullName.SetValue("A Cheung Limited");
add.TxnDate.SetValue(DateTime.Today);
IExpenseLineAdd line = add.ExpenseLineAddList.Append();
line.AccountRef.FullName.SetValue("Travel & Lodging");
line.Amount.SetValue(100.00);
IResponse response = sessionManager.DoRequests(MsgRequest).ResponseList.GetAt(0);
MessageBox.Show(response.StatusMessage);
I have an application that builds an HTML email. Included in the content is an encoded URL parameter that might, for example, contain a promotional code or product reference. The email is generated by a Windows service (essentially a console application) and the link, when clicked is handled by an MVC web site. Here is the code for creating the email link:
string CreateLink(string domain, string code) {
// code == "xyz123"
string encrypted = DES3Crypto.Encrypt(code); // H3uKbdyzrUo=
string urlParam = encrypted.EncodeBase64(); // SDN1S2JkeXpyVW890
return domain + "/" + urlParam;
}
The action method on the MVC controller is constructed as follows:
public ActionResult Index(string id) {
string decoded = id.DecodeBase64();
string decrypted = DES3Crypto.Decrypt(decoded);
...
}
In all our testing, this mechanism has worked as expected, however, now we have gone live we are seeing around a 4% error rate where the conversion from base-64 fails with the following exception:
The input is not a valid Base-64 string as it contains a non-base 64 character, more than two padding characters, or a non-white space character among the padding characters.
The id parameter from the url 'looks' OK. The problem appears to be with the EncodeBase64/DecodeBase64 methods that are failing as DecodeBase64 method returns a 'garbled' string such as "�nl����□��7y�b�8�sJ���=" on the failed links.
Furthermore, most of the errors are from IE6 user agents leading me to think this is a character encoding problem but I don't see why.
For reference, here is the code for my base-64 URL encoding:
public static string EncodeBase64(this string source)
{
byte[] bytes = Encoding.UTF8.GetBytes(source);
string encodedString = HttpServerUtility.UrlTokenEncode(bytes);
return encodedString;
}
public static string DecodeBase64(this string encodedString)
{
byte[] bytes = HttpServerUtility.UrlTokenDecode(encodedString);
string decodedString = Encoding.UTF8.GetString(bytes);
return decodedString;
}
Any advice would be much appreciated.
To recap, I was creating a URL that used a base-64 encoded parameter which was itself a Triple DES encrypted string. So the URL looked like http://[Domain_Name]/SDN1S2JkeXpyVW890 The link referenced a controller action on an MVC web site.
The URL was then inserted into an HTML formatted email. Looking at the error log, we saw that around 5% of the public users that responded to the link were throwing an "invalid base-64 string error". Most, but not all, of these errors were related to the IE6 user agent.
After trying many possible solutions based around character and URL encoding, it was discovered that somewhere in the client's process the url was being converted to lower-case - this, of course, broke the base-64 encoding (as it is uses both upper and lower case encoding characters).
Whether the case corruption was caused by the client's browser, email client or perhaps local anti-virus software, I have not been able to determine.
The Solution
Do not use any of the standard base-64 encoding methods, instead use a base-32 or zBase-32 encoding instead - both of which are case-insensitive.
See the following links for more details
Base-32 - Wikipedia
MyTenPennies Base-32 .NET Implementation
The moral of the story is, Base-64 URL encoding can be unreliable in some public environments. Base-32, whilst slightly more verbose, is a better choice.
Hope this helps.
It looks like you were really close. You had an extra zero coming back from your encyrpted.EncodeBase64() function.
Try this:
string data = "H3uKbdyzrUo=";
string b64str = Convert.ToBase64String(UTF8Encoding.UTF8.GetBytes(data));
string clearText = UTF8Encoding.UTF8.GetString(Convert.FromBase64String(b64str));
This is an interesting issue. My guess is that IE 6 is eating some of the characters.
For example, the length of the string that you included "ywhar0xznxpjdnfnddc0yxzbk2jnqt090" is not a multiple of four (which is a requirement for FromBase64 to work http://msdn.microsoft.com/en-us/library/system.convert.frombase64string.aspx)
But if you were to pad that string until it's length is a multiple of four ("ywhar0xznxpjdnfnddc0yxzbk2jnqt090" + "a12") then that works.
The MSDN documentation says that one ("=") or two ("==") equal characters are used for padding to/fromBase64 methods and I suspect IE 6 is truncating that from the string that you send.
This is total speculation but I hope it helps.