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Scan Uploaded File using Sophos Labs Intelix in c#

I am new to SophosLabs Intelix. I am trying to build a sample in my ASP .Net Application(webforms/MVC) in which I want to run an Antivirus Scan on the uploaded file by the User. If the Uploaded file is clean I want to upload it to the server else I want to cancel the operation. I want to specifically use SophosLabs Intelix for the functionality. It would be great if someone can guide me regarding this functionality. A code sample in C# would be appreciated a lot.
Thanks in advance for your help.
Sample:
if(file.HasFile)
{
//run an antivirus scan
//result
if(result == NoThreat){
//Uploaded Successfully
}
else{
//File contains a virus. Upload failed!
}
}
else{
//Please select a file to upload!
}

I suggest to start with the implementation of OAUTH 2 authentication request. You can find some ideas here: How do I get an OAuth 2.0 authentication token in C#
As soon as you have the access_token you can use if for /reports/?sha256=... query.
It may return the report immediately.
If it does not return any data (404) this request was free and you can POST the file to the root endpoint "/" for analysis.
It can take a few seconds/minutes, during that you should poll the report from /reports/{job_id} endpoint as long as you get it.
If you cannot wait minutes for decision data, you may use the File Hash Lookup API as well that returns immediately.
It may give a reputationScore between 30..69 so cannot decide how dangerous the file is, but in this case you can still perform a static or dynamic analysis on it.

How to upload to OneDrive using Microsoft Graph Api in c#

I have been trying to upload to a OneDrive account and I am hopelessly stuck not being able to upload neither less or greater than 4MB files. I have no issues accessing the drive at all, since I have working functions that create a folder, rename files/folders, and a delete files/folders.
https://learn.microsoft.com/en-us/graph/api/driveitem-put-content?view=graph-rest-1.0&tabs=csharp
This documentation on Microsoft Graph API is very friendly to HTTP code, and I believe I am able to fairly "translate" the documentation to C#, but still fail to grab a file and upload to OneDrive. Some places online seem to be using byte arrays? Which I am completely unfamiliar with since my primary language is C++ and we just use ifstream/ofstream. Anyways, here is the portion of code in specific (I hope this is enough):
var item = await _client.Users[userID].Drive.Items[FolderID]//"01YZM7SMVOQ7YVNBXPZFFKNQAU5OB3XA3K"].Content
.ItemWithPath("LessThan4MB.txt")//"D:\\LessThan4MB.txt")
.CreateUploadSession()
.Request()
.PostAsync();
Console.WriteLine("done printing");
As it stands, it uploads a temporary file that has a tilde "~" in the OneDrive (like as if I was only able to open but not import any data from the file onto it). If I swap the name of the file so it includes the file location it throws an error:
Message: Found a function 'microsoft.graph.createUploadSession' on an open property. Functions on open properties are not supported.

Try this approach with memory stream and PutAsync<DriveItem> request:
string path = "D:\\LessThan4MB.txt";
byte[] data = System.IO.File.ReadAllBytes(path);
using (Stream stream = new MemoryStream(data))
{
var item = await _client.Me.Drive.Items[FolderID]
.ItemWithPath("LessThan4MB.txt")
.Content
.Request()
.PutAsync<DriveItem>(stream);
}
I am assuming you have already granted Microsoft Graph Files.ReadWrite.All permission. Check your API permission. I tested this code snippet with pretty old Microsoft.Graph library version 1.21.0. Hopefully it will work for you too.

Azure Function fails to find file

I have an azure function that uses the Azure context. When I execute my function from visual studio 2019 on my machine, it executes correctly. However when I publish this to my Azure account, I get an error that the my.azureauth file cannot be found.
Could not find file 'D:\Program Files (x86)\SiteExtensions\Functions\2.0.12950\32bit\my.azureauth'
The code that is used:
var authFilePath = "my.azureauth";
Console.WriteLine($"Authenticating with Azure using credentials in file at {authFilePath}");
azure = Azure.Authenticate(authFilePath).WithDefaultSubscription();
sub = azure.GetCurrentSubscription();
Console.WriteLine($"Authenticated with subscription '{sub.DisplayName}' (ID: {sub.SubscriptionId})");
This is code that I found on one of the Microsoft tutorials. I have set my my.azureauth file to "Copy Always".
Could anyone point my in the right direction?

You are get this file path because the Directory.GetCurrentDirectory() would return D:\Program Files (x86)\SiteExtensions\Functions\2.0.12950\32bit instead of D:\home\site\wwwroot\ or D:\home\site\wwwroot\FunctionName.
And if you want to get the wwwroot folder or the function app directory you should use ExecutionContext. Further more information you could refer to this wiki doc.
So the right file path should be context.FunctionDirectory+"\my.azureauth" or context.FunctionAppDirectory+"\my.azureauth", which one to use depends on where your file is stored.

I have found that Kudu is extremely useful in seeing what has been deployed to Azure.
Navigate to your function in the Azure portal.
The instructions here will help get to the kudu console.
https://www.gslab.com/blogs/kudu-azure-web-app
From there you can browse the files which have been deployed into your function's file system.
If you add " , ExecutionContext context)" at the end of the function's run entry point, you can then get the folder which your function is running from with "var path = context.FunctionAppDirectory;
PS apologies for any formatting I am editing this on my phone.

Welcome to Stackoverflow.
Firstly, I'd recommend strongly against using file-based authentication as shown in your question.
From notes:
Note, file-based authentication is an experimental feature that may or may not be available in later releases. The file format it relies on is subject to change as well.
Instead, I would personally store the connection string details (AzureCredentials) in the config file (Web/SiteSettings) and use the provided constructor...
Again, the below are taken from the documentation notes:
Similarly to the file-based approach, this method requires a service principal registration, but instead of storing the credentials in a local file, the required inputs can be supplied directly via an instance of the AzureCredentials class:
var creds = new AzureCredentialsFactory().FromServicePrincipal(client, key, tenant, AzureEnvironment.AzureGlobalCloud);
var azure = Azure.Authenticate(creds).WithSubscription(subscriptionId);
or
var creds = new AzureCredentialsFactory().FromServicePrincipal(client, pfxCertificatePath, password, tenant, AzureEnvironment.AzureGlobalCloud);
var azure = Azure.Authenticate(creds).WithSubscription(subscriptionId);
where client, tenant, subscriptionId, and key or pfxCertificatePath and password are strings with the required pieces of information about your service principal and subscription. The last parameter, AzureEnvironment.AzureGlobalCloud represents the Azure worldwide public cloud. You can use a different value out of the currently supported alternatives in the AzureEnvironment enum.
The first example is most likely the one you should be looking at.
The notes I got this information from can be accessed here.

If you have some problems with AAD, these screenshots may help you.
Client ID:
Key:
Please note that the Key value can only be copied when it is created, after which it will be hidden.
Hope this helps you get started with AAD quickly.

c# file upload to AWS

Hello and apologies in advance for the noob question. I'm also relatively new to c#. In ASP.NET core, I can save files via the file upload control to AWS S3. However, this relies on me saving the files first to a location on my hard drive and then I can send in the path for the AWS code to pick it up from there. I'm sure it will be a simple answer but I can't find this after a few days' searching. As anyone who uses my site can upload (and later download) pdfs and jpegs, how do I either (1) save the file to a temporary location on their machine or phone, or, preferably, (2) 'somehow' send in the path so the AWS code can pick it up? There are many posts stating how you can't get at the path for security reasons but as far as I can tell, the AWS code relies on it.
Here's the AWS code I'm using (from their documentation). It works for me (overwrites the last file and there's no error handling yet, but one thing at once for me). The bucketName and keyName are set up elsewhere.
It's how to send in the filePath without saving it anywhere that I can't get to work. The error just says that it can't find the file, understandably.
public void FileProcess(string filePath)
{
client = new AmazonS3Client(Amazon.RegionEndpoint.EUWest2);
Amazon.S3.Model.PutObjectRequest request = new Amazon.S3.Model.PutObjectRequest()
{
BucketName = bucketName,
Key = keyName,
FilePath = filePath
};
PutObjectResponse response2 = client.PutObject(request);
}

Get last modified date of a remote file

I have an app with which at startup it downloads a file from a remote location (through the net) and parses it's contents.
I am trying to speed up the process of startup as the bigger the file gets the slower the app starts.
As a way to speed up the process I thought of getting the last modified date of the file and if it is newer from the file on the user's pc then and only then download it.
I have found many ways to do it online but none of them are in C# (for windows store apps). Does anybody here know of a way of doing this without the need to download the file? If I am to download the file then the process is sped up at all.
My C# code for downloading the file currently is this
const string fileLocation = "link to dropbox";
var uri = new Uri(fileLocation);
var downloader = new BackgroundDownloader();
StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync("feedlist.txt",CreationCollisionOption.ReplaceExisting);
DownloadOperation download = downloader.CreateDownload(uri, file);
await download.StartAsync();
If it helps the file is stored in dropbox but if any of you guys have a suggestion for another free file hosting service I am open to suggestions

Generally, you can check the file time by sending HEAD request and parsing/looking HTTP header response for a Last-Modified filed. The remote server should support it and DropBox does not support this feature for direct links (only via API). But DropBox have another feature, the headers have the etag field. You should store it and check in the next request. If it changed - the file has been changed too. You can use this tool to check the remote file headers.