Develop Reference

Does UnityWebRequest.uploadProgress have side effects?

I have the following upload code using Unity's UnityWebRequest API (Unity 2019.2.13f1):
public IEnumerator UploadJobFile(string jobId, string path)
{
if (!File.Exists(path))
{
Debug.LogError("The given file to upload does not exist. Please re-create the recording and try again.");
yield break;
}
UnityWebRequest upload = new UnityWebRequest(hostURL + "/jobs/upload/" + jobId);
upload.uploadHandler = new UploadHandlerFile(path);
upload.downloadHandler = new DownloadHandlerBuffer();
upload.method = UnityWebRequest.kHttpVerbPOST;
upload.SetRequestHeader("filename", Path.GetFileName(path));
UnityWebRequestAsyncOperation op = upload.SendWebRequest();
while (!upload.isDone)
{
//Debug.Log("Uploading file...");
Debug.Log("Uploading file. Progress " + (int)(upload.uploadProgress * 100f) + "%"); // <-----------------
yield return null;
}
if (upload.isNetworkError || upload.isHttpError)
{
Debug.LogError("Upload error:\n" + upload.error);
}
else
{
Debug.Log("Upload success");
}
// this is needed to clear resources on the file
upload.Dispose();
}
string hostURL = "http://localhost:8080";
string jobId = "manualUploadTest";
string path = "E:/Videos/short.mp4";
void Update()
{
if (Input.GetKeyDown(KeyCode.O))
{
Debug.Log("O key was pressed.");
StartCoroutine(UploadAndTest(jobId, path));
}
}
And the files I receive on the server side arrive broken, especially if they are larger (30 MB or more). They are missing bytes in the end and sometimes have entire byte blocks duplicated in the middle.
This happens both when testing client and server on the same machine or when running on different machines.
The server does not complain - from its perspective, no transport errors happened.
I noticed that if I comment out the access to upload.uploadProgress (and e.g. instead use the commented-out debug line above it which just prints a string literal), the files stay intact. Ditching the wile loop altogether and replacing it with yield return op also works.
I tested this strange behavior repeatedly in an outer loop - usually after at most 8 repetitions with the "faulty" code, the file appears broken. If I use the "correct" variant, 100 uploads (update: 500) in a row were successful.
Has upload.uploadProgress side-effects? For what it's worth, the same happens if I print op.progress instead - the files are also broken.

This sounds like a real bug. uploadProgress obviously should not have side effects.

Task hang infinitely when calling .Wait() in kafka-net

I'm currently trying to post messages from a for-loop on a kafka server running on my local machine using the kafka-net library in c# (https://github.com/Jroland/kafka-net), following the example given on the linked repo, my code is the following.
string kafkaServer = "http://" + ip + ":" + port;
Uri uri = new Uri(kafkaServer);
var options = new KafkaOptions(uri);
var router = new BrokerRouter(options);
var client = new Producer(router);
...
foreach(string sumup in LS){
payloadJson["fullPathDataFolder"] = remoteFolder;
payloadJson["globalName"] = GloablName;
payloadJson["name"] = name;
payloadJson["text"] = sumUp + "\n";
payloadJson["type"] = type;
string payload = payloadJson.ToString();
KafkaNet.Protocol.Message msg = new KafkaNet.Protocol.Message(payload);
client.SendMessageAsync(topic, new List<KafkaNet.Protocol.Message> { msg }).Wait();
}
This code run through the first iteration and i'm able to retrieve the first string from a second machine linked to the same server with a consumer.
Then the code here above remain stuck at the intruction:
client.SendMessageAsync(topic, new List<KafkaNet.Protocol.Message> { msg }).Wait();
If now I remove the .Wait() this code run quite fast but it randomly ignore some of the string i send
What am I missing ?
P.S.
I'v tried also to use Confluent.kafka and i got similar problems
P.P.S.
It's important that this program run sequentially.

How to make geo location retrieval process faster in UWP?

I am using Geolocator class to find current position of the device in UWP app. The location retrieval process works very fast in my compute. But when I try to run the same app in real device, then device retrieval process takes around 30 seconds.
I'm using the following code snippet:
var accessStatus = await Geolocator.RequestAccessAsync();
if (accessStatus == GeolocationAccessStatus.Allowed)
{
Geolocator geolocator = new Geolocator
{
DesiredAccuracyInMeters = 500,
DesiredAccuracy = PositionAccuracy.High
};
Geoposition pos = await geolocator.GetGeopositionAsync()
}
How can I make this process faster in my devices?
Already tried by increasing the DesiredAccuracyInMeters value upto 2000 but couldn't find any improvement. Thanks in advance.

If you check the documentation, you can see that when you set both DesiredAccuracy and DesiredAccuracyInMeters, the one set last takes precedence:
When neither DesiredAccuracyInMeters nor DesiredAccuracy are set, your app will use an accuracy setting of 500 meters (which corresponds to the DesiredAccuracy setting of Default). Setting DesiredAccuracy to Default or High indirectly sets DesiredAccuracyInMeters to 500 or 10 meters, respectively. When your app sets both DesiredAccuracy and DesiredAccuracyInMeters, your app will use whichever accuracy value was set last.
So you because you are setting DesiredAccuracy to High, you are effectively overriding the meters setting. To make the search faster, do not set the High accuracy and only set the meters value.

I will add to Martin's question, you should use first the cached position and then use the GetPositionAsync, you should get a faster localization of the user in this way:
var locator = CrossGeolocator.Current;
locator.DesiredAccuracy = 500;
//Check if we have a cached position
var loc = await locator.GetLastKnownLocationAsync ();
if ( loc != null )
{
CurrentPosition = new Position (loc.Latitude, loc.Longitude);
}
if ( !locator.IsGeolocationAvailable || !locator.IsGeolocationEnabled )
{
return;
}
//and if not we get a new one
var def = await locator.GetPositionAsync (TimeSpan.FromSeconds (10), null, true);
CurrentPosition = new Position (def.Latitude, def.Longitude);

Is there a way to check if a printing process was successful?

I have an application where I need to print a ticket. Each ticket must be unique. The application is windows forms and written entirely in c#. For our application we're using Samsung ML- 2525 laser monochromatic printers.
The flow is basically the following, the operator picks a product/ticket (which is unique) and then it presses a button that does 2 things:
Connects to a database and updates the product as used
Prints the ticket (this is done using System.Drawing and GDI+)
For some reason, every once in a while, the image that needs to be printed is not sent to the printer. It's a rare case, but it happens.
I tried to connect to the printer using Win32_Printer ( http://msdn.microsoft.com/en-us/library/Aa394363 ) but I can't get to get the current printer's state (online, offline, low toner, paper jam, etc). I can only check if the printer exists and that the paper size is installed correctly. I tried code similar to the following but it didn't work
private string MonitorPrintJobWmi()
{
var jobMessage = String.Empty;
var scope = new ManagementScope(ManagementPath.DefaultPath);
scope.Connect();
var selectQuery = new SelectQuery { QueryString = #"select * from Win32_PrintJob" };
var objSearcher = new ManagementObjectSearcher(scope, selectQuery);
var objCollection = objSearcher.Get();
foreach (var job in objCollection)
{
if (job != null)
{
jobMessage += String.Format("{0} \r\n", job["Name"].ToString());
jobMessage += String.Format("{0} \r\n", job["JobId"].ToString());
_jobId = Convert.ToInt32(job["JobId"]);
jobMessage += String.Format("{0} \r\n", job["JobStatus"].ToString());
jobMessage += String.Format("{0} \r\n", job["Status"].ToString());
}
}
return jobMessage;
}
I tried to get an API for the printer but I couldn't get a hold of it. By the way, the printer's software do indicate different errors in the windows toolbar.
My question is if anyone can lead me in the right direction as to how to connect to a printer and check if printing was successful.
Also, it would be helpful if someone know of some other specific printer in which I may accomplish this ie, changing hardware.
Thanks,

To get a list of print queues on the local machine, try PrintServer's GetPrintQueues method.
Once you have an instance of the PrintQueue object associated with the relevant printer, you can use it to access the printer's status (IsOffline, IsPaperOut, etc.). Also, you can use it to get a list of the jobs in the given queue (GetPrintJobInfoCollection) which then will allow you to get job-specific status information (IsInError, IsCompleted, IsBlocked, etc.).
Hope this helps!

After try to print your PrintDocument (System.Drawing.Printing), try to check status of printjobs.
First step: Initialize your printDocument.
Second step: Get your printer Name From System.Drawing.Printing.PrinterSettings.InstalledPrinters.Cast<string>();
And copy it into your printerDocument.PrinterSettings.PrinterName
Third step: Try to print and dispose.
printerDocument.Print();
printerDocument.Dispose();
Last step: Run the check in a Task (do NOT block UI thread).
Task.Run(()=>{
if (!IsPrinterOk(printerDocument.PrinterSettings.PrinterName,checkTimeInMillisec))
{
// failed printing, do something...
}
});
Here is the implementation:
private bool IsPrinterOk(string name,int checkTimeInMillisec)
{
System.Collections.IList value = null;
do
{
//checkTimeInMillisec should be between 2000 and 5000
System.Threading.Thread.Sleep(checkTimeInMillisec);
// or use Timer with Threading.Monitor instead of thread sleep
using (System.Management.ManagementObjectSearcher searcher = new System.Management.ManagementObjectSearcher("SELECT * FROM Win32_PrintJob WHERE Name like '%" + name + "%'"))
{
value = null;
if (searcher.Get().Count == 0) // Number of pending document.
return true; // return because we haven't got any pending document.
else
{
foreach (System.Management.ManagementObject printer in searcher.Get())
{
value = printer.Properties.Cast<System.Management.PropertyData>().Where(p => p.Name.Equals("Status")).Select(p => p.Value).ToList();
break;
}
}
}
}
while (value.Contains("Printing") || value.Contains("UNKNOWN") || value.Contains("OK"));
return value.Contains("Error") ? false : true;
}
Good luck.

Get closest Domain Controller in current AD site without hard coding information

For instances when Active Directory takes too long to replicate data between sites, I need to ensure that the local AD replica contains the most up to date information.
How can I get a list of DomainControllers for the current site?
I haven't found anything on Codeproject or on StackOverflow

Going to all this trouble is probably wasted effort. Unless you are experiencing issues with the built in logic for finding a domain controller you should just go with the built in method that returns one. According to Microsoft it automatically tries to find the closes one: http://technet.microsoft.com/en-us/library/cc978016.aspx.
Just use the static DomainController.FindOne method and pass in your directorycontext.
Update
Alright, try the code below, let me know how it works for you. It pings each, returns the roundtrip time, if -1 (no connection) it skips it. Flags PDC status if present. Orders by PDC status, followed by ping round trip.
static void Main(string[] args)
{
var dcsInOrder = (from DomainController c in Domain.GetCurrentDomain().DomainControllers
let responseTime = Pinger(c.Name)
where responseTime >=0
let pdcStatus = c.Roles.Contains(ActiveDirectoryRole.PdcRole)
orderby pdcStatus, responseTime
select new {DC = c, ResponseTime = responseTime}
).ToList();
foreach (var dc in dcsInOrder)
{
System.Console.WriteLine(dc.DC.Name + " - " + dc.ResponseTime);
}
System.Console.ReadLine();
}
private static int Pinger(string address)
{
Ping p = new Ping();
try
{
PingReply reply = p.Send(address, 3000);
if (reply.Status == IPStatus.Success) return (int)reply.RoundtripTime;
}
catch { }
return -1;
}

First, I'll answer the question that you actually asked:
System.DirectoryServices.ActiveDirectory.ActiveDirectorySite.GetComputerSite().Servers
But it seems like you're asking how to make sure that you're talking to the closest domain controller possible. Windows doesn't exactly provide this functionality, the best it will do is give you a domain controller in the same site that the code is running from.
I think the first thing to check is that you have your sites and subnets configured correctly. Run Active Directory Sites and Services, and make sure that subnets and domain controllers are assigned to the correct sites.
This MSDN page (and the Technet article in Peter's answer) says that you must be searching by the DNS name for the DC Locator to attempt to find a DC in the current site. I don't know if the Name property of the Domain class is the DNS domain name.
I have to assume that DomainController.FindOne is a wrapper for DsGetDcName. At that link, you can find how to turn on tracing for that function. You can use this if you still have problems, or maybe you should just PInvoke this function.

Here is a code sample that has no hard coding of DCs. Comments and criticism are welcome.
/// <summary>
/// For best results ensure all hosts are pingable, and turned on.
/// </summary>
/// <returns>An ordered list of DCs with the PDCE first</returns>
static LinkedList<DomainController> GetNearbyDCs()
{
LinkedList<DomainController> preferredDCs = new LinkedList<DomainController>();
List<string> TestedDCs = new List<string>();
using (var mysite = ActiveDirectorySite.GetComputerSite())
{
using (var currentDomain = Domain.GetCurrentDomain())
{
DirectoryContext dctx = new DirectoryContext(DirectoryContextType.Domain, currentDomain.Name);
var listOfDCs = DomainController.FindAll(dctx, mysite.Name);
foreach (DomainController item in listOfDCs)
{
Console.WriteLine(item.Name );
if (IsConnected(item.IPAddress))
{
// Enumerating "Roles" will cause the object to bind to the server
ActiveDirectoryRoleCollection rollColl = item.Roles;
if (rollColl.Count > 0)
{
foreach (ActiveDirectoryRole roleItem in rollColl)
{
if (!TestedDCs.Contains(item.Name))
{
TestedDCs.Add(item.Name);
if (roleItem == ActiveDirectoryRole.PdcRole)
{
preferredDCs.AddFirst(item);
break;
}
else
{
if (preferredDCs.Count > 0)
{
var tmp = preferredDCs.First;
preferredDCs.AddBefore(tmp, item);
}
else
{
preferredDCs.AddFirst(item);
}
break;
}
}
}
}
else
{
// The DC exists but has no roles
TestedDCs.Add(item.Name);
if (preferredDCs.Count > 0)
{
var tmp = preferredDCs.First;
preferredDCs.AddBefore(tmp, item);
}
else
{
preferredDCs.AddFirst(item);
}
}
}
else
{
preferredDCs.AddLast(item);
}
}
}
}
return preferredDCs;
}
static bool IsConnected(string hostToPing)
{
string pingurl = string.Format("{0}", hostToPing);
string host = pingurl;
bool result = false;
Ping p = new Ping();
try
{
PingReply reply = p.Send(host, 3000);
if (reply.Status == IPStatus.Success)
return true;
}
catch { }
return result;
}

Here's my approach using powershell but I'm sure it's a simple implementation in c#, etc. If DHCP is setup correctly, the Primary DNS server in your subnet should be the closest Domain Controller. So the following code should grab the first DNS IP and resolve it to the hostname of the closest DC. This doesn't require RSAT or credentials and contains no specific properties of the current domain.
$NetItems = #(Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "IPEnabled = 'True'" -ComputerName $env:COMPUTERNAME)
foreach ($objItem in $NetItems)
{
if ($objItem.{DNSServerSearchOrder}.Count -ge 1)
{
$PrimaryDNS = $objItem.DNSServerSearchOrder[0]
$domain = $objItem.DNSDomain
break
}
}
[System.Net.Dns]::GetHostbyAddress($PrimaryDNS).hostname -replace ".$($domain)",""