Add JSON string directly to Azure Blob Storage Container using C#

Question

I am trying to load a JSON string (serialized with Newtonsoft.Json) without creating a temporary file.

I am serializing object in runtime using JsonConvert.SerializeObject(obj,settings) which returns a string.

Following Microsoft documentation I could do as it's illustrated below:

// Create a local file in the ./data/ directory for uploading and downloading
string localPath = "./data/";
string fileName = "quickstart" + Guid.NewGuid().ToString() + ".txt";
string localFilePath = Path.Combine(localPath, fileName);

// Write text to the file
await File.WriteAllTextAsync(localFilePath, "Hello, World!");

// Get a reference to a blob
BlobClient blobClient = containerClient.GetBlobClient(fileName);

Console.WriteLine("Uploading to Blob storage as blob:\n\t {0}\n", blobClient.Uri);

// Open the file and upload its data
using FileStream uploadFileStream = File.OpenRead(localFilePath);
await blobClient.UploadAsync(uploadFileStream, true);
uploadFileStream.Close();

Although it works, I would have to create temporary file for each uploaded JSON file.

I tried this:

BlobServiceClient blobServiceClient = new BlobServiceClient("SECRET");

BlobContainerClient container = BlobServiceClient.GetBlobContainerClient("CONTAINER_NAME");

container.CreateIfNotExistsAsync().Wait();

container.SetAccessPolicy(Azure.Storage.Blobs.Models.PublicAccessType.Blob);

CloudBlockBlob cloudBlockBlob = new CloudBlockBlob(container.Uri);

var jsonToUplaod = JsonConvert.SerializeObject(persons, settings);

cloudBlockBlob.UploadTextAsync(jsonToUpload).Wait();

But, well...it doesn't have right to work as I am not specifing any actual file in the given container (I don't know where to do it).

Is there any way to upload a blob directly to a given container?

Thank You in advance.

Answer 1

The BlobClient class wants a Stream, so you can create a MemoryStream from your JSON string.
Try something like this:

BlobClient blob = container.GetBlobClient("YourBlobName");

using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonToUpload)))
{
    await blob.UploadAsync(ms);
}