Uploading and Downloading files¶

The following guide will show you how you can start uploading or downloading files with the Storage Accounts exposed by Bane NOR

Information¶

The blob store (storage container) is accessible from API Management which is just a proxy in front of a Storage Account.
To be able to upload and download files, your service needs an Entra identity with correct access to the blob store. Check out our guide on how to receive this here: Skyporten
Since our API uses Microsofts own blob storage API, all methods from Azure Blob Storage client library will work.

Nuget¶

To be able to use the code example, the following Nuget packages are needed:

Global Nuget Packages:

Azure.Identity
Azure.Storage.Blobs

Easy ASP.NET program.cs¶

The example below showcases a C# program for uploading a file using the payload manager storage account API. More in-depth examples can be seen in Microsoft documentation linked to at the top of this article.

Upload with Skyporten¶

using Azure.Identity;  
using Azure.Storage.Blobs;  
  
// This method uses private/public key pair, can also be done with certificates
var maskinPortenOptions = new MaskinportenOptions()  
{  
    ClientId = "id-of-your-self-service-integration",   
    Audience = "https://test.sky.maskinporten.no", // Prod: "https://sky.maskinporten.no"  
    KeyId = "id-for-your-key",  
    Url = new Uri("https://test.sky.maskinporten.no/token"),  // Prod: "https://sky.maskinporten.no/token"   
};  
  
// Our implementation for fetching token from maskinporten
var httpClient = new HttpClient();  
var tokenGenerator = new TokenGenerator(maskinPortenOptions, httpClient);  
var header = await tokenGenerator.GetAuthenticationHeaderValueAsync();  

// ManagedIdentityClientId is provided by integration team
var AzureTenantId = "6ee535f2-3064-4ac9-81d8-4ceb2ff790c6";  
var ManagedIdentityClientId = "client-id";  
var tokenPath = "/tmp/maskinporten-token.txt";  
await File.WriteAllTextAsync(tokenPath, header.Parameter); //header.parameter = token received from maskinporten

// By setting these environment variables, DefaultAzureCredential uses them automatically
// for the workloadIdentityCredential flow which handles token exchange automatically.
Environment.SetEnvironmentVariable("AZURE_CLIENT_ID", clientId);
Environment.SetEnvironmentVariable("AZURE_TENANT_ID", tenantId);
Environment.SetEnvironmentVariable("AZURE_FEDERATED_TOKEN_FILE", tokenPath);

var defaultAzureCredential = new DefaultAzureCredential();

// Use correct storage account
var blobClientOptions = new BlobClientOptions()
{
    Audience = "https://bnplmextnwesttest.blob.core.windows.net"
};

// Use correct API environment
var blobServiceClient = new BlobServiceClient(  
    new Uri("https://test.api.apps.banenor.no/payload-manager/v1"), workLoadIdentity, blobClientOptions);  

string containerName = "container-name";  
  
var containerClient = blobServiceClient.GetBlobContainerClient(containerName);  
  
// Create a local file in the ./data/ directory for uploading and downloading  
string localPath = "data";  
Directory.CreateDirectory(localPath);  
string fileName = "quickstart" + Guid.NewGuid().ToString() + ".txt";  
string localFilePath = Path.Combine(localPath, fileName);  
await File.WriteAllTextAsync(localFilePath, "Hello, World!");  

// Microsoft SDK is not able to correctly add /path/to/folder/ so you must re-specify version and container-name
BlobClient blobClient = containerClient.GetBlobClient("v1/container-name/path/to/folder/" + fileName);

  
await blobClient.UploadAsync(localFilePath, false);