Is Microsoft planning on to create a method in Azure BlobService that fetches data to the storage from a public URI? Quick google search shows it had something similar in the past, but API is outdated now.
Please have a try to use CloudBlockBlob.StartCopy or CloudBlockBlob.StartCopyAsync,it can work correctly. I write a demo for it.More info about the CloudBlockBlob.StartCopy please refer to the article.
CloudStorageAccount storageAccount = CloudStorageAccount.Parse("Storage connection string");
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
CloudBlobContainer container = blobClient.GetContainerReference("newcontainer"); //container name
var source = new Uri("public file url");
CloudBlockBlob target = container.GetBlockBlobReference("targe blob name");
target.StartCopy(source);
//or target.StartCopyAsync(source).Wait();
Update:
I did a test with copy blob api, detail info please refer to the screenshot.
Related
I have prepared some C# code to create a container in the Azure Storage and then I am uploading a file into that azure container. The code is below:
var connectionString = _settings.appConfig.StorageConnectionString;
BlobServiceClient blobServiceClient = new BlobServiceClient(connectionString);
BlobContainerClient blobContainer = blobServiceClient.GetBlobContainerClient("nasir-container");
await blobContainer.CreateIfNotExistsAsync(); // Create the container.
BlobClient blobClient = blobContainer.GetBlobClient(fileName); // Creating the blob
string fileName = "D:/Workspace/Adappt/MyWordFile.docx";
FileStream uploadFileStream = System.IO.File.OpenRead(fileName);
blobClient.Upload(uploadFileStream);
uploadFileStream.Close();
Now I have updated my MyWordFile.docx with more content. Now I would like to upload this updated file to the same blob storage. How can I do this? I also want to create versioning too so that I can get the file content based on the version.
Now I have updated my MyWordFile.docx with more content. Now I would
like to upload this updated file to the same blob storage. How can I
do this?
To update a blob, you simply upload the same file (basically use the same code you wrote to upload the file in the first place). Upload operation will overwrite an existing blob.
I also want to create versioning too so that I can get the file
content based on the version.
There are two ways you can implement versioning for blobs:
Automatic versioning: If you want Azure Blob Storage service to maintain versions of your blobs, all you need to do is enable versioning on the storage account. Once you enable that, anytime a blob is modified a new version of the blob will be created automatically for you by service. Please see this link to learn more about blob versioning: https://learn.microsoft.com/en-us/azure/storage/blobs/versioning-overview.
Manual versioning: While automatic versioning is great but there could be many reasons why you would want to opt for manual versioning (e.g. you only want to version a few blobs and not all blobs, you are not using V2 Storage account etc.). If that's the case, then you can create a version of the blob by taking a snapshot of the blob before you update the blob. Snapshot creates a read-only copy of the blob at the point of time snapshot was taken. Please see this link to learn more about blob snapshot: https://learn.microsoft.com/en-us/azure/storage/blobs/snapshots-overview.
First you need to enable versioning in the blob storage through the portal in the storage account.
Just click on Disable it will take you to a different page and select enable version and click save
Here after uploading the blob when you update the blob it will automatically trigger the creating of versions.
public static async Task UpdateVersionedBlobMetadata(BlobContainerClient blobContainerClient,
string blobName)
{
try
{
// Create the container.
await blobContainerClient.CreateIfNotExistsAsync();
// Upload a block blob.
BlockBlobClient blockBlobClient = blobContainerClient.GetBlockBlobClient(blobName);
string blobContents = string.Format("Block blob created at {0}.", DateTime.Now);
byte[] byteArray = Encoding.ASCII.GetBytes(blobContents);
string initalVersionId;
using (MemoryStream stream = new MemoryStream(byteArray))
{
Response<BlobContentInfo> uploadResponse =
await blockBlobClient.UploadAsync(stream, null, default);
// Get the version ID for the current version.
initalVersionId = uploadResponse.Value.VersionId;
}
// Update the blob's metadata to trigger the creation of a new version.
Dictionary<string, string> metadata = new Dictionary<string, string>
{
{ "key", "value" },
{ "key1", "value1" }
};
Response<BlobInfo> metadataResponse =
await blockBlobClient.SetMetadataAsync(metadata);
// Get the version ID for the new current version.
string newVersionId = metadataResponse.Value.VersionId;
// Request metadata on the previous version.
BlockBlobClient initalVersionBlob = blockBlobClient.WithVersion(initalVersionId);
Response<BlobProperties> propertiesResponse = await initalVersionBlob.GetPropertiesAsync();
PrintMetadata(propertiesResponse);
// Request metadata on the current version.
BlockBlobClient newVersionBlob = blockBlobClient.WithVersion(newVersionId);
Response<BlobProperties> newPropertiesResponse = await newVersionBlob.GetPropertiesAsync();
PrintMetadata(newPropertiesResponse);
}
catch (RequestFailedException e)
{
Console.WriteLine(e.Message);
Console.ReadLine();
throw;
}
}
static void PrintMetadata(Response<BlobProperties> propertiesResponse)
{
if (propertiesResponse.Value.Metadata.Count > 0)
{
Console.WriteLine("Metadata values for version {0}:", propertiesResponse.Value.VersionId);
foreach (var item in propertiesResponse.Value.Metadata)
{
Console.WriteLine("Key:{0} Value:{1}", item.Key, item.Value);
}
}
else
{
Console.WriteLine("Version {0} has no metadata.", propertiesResponse.Value.VersionId);
}
}
The above code is from the following documentation.
I am trying to get a file from Azure container. I need to read its content.
The file has been uploaded to umbraco media, media are stored in our Azure container.
Its normal (umbraco) url would be like:
~/media/10890/filename.xls
I am trying to retrieve it like this:
var storageAccount = CloudStorageAccount.Parse(ConfigurationManager.AppSettings["strorageconnstring"]);
var blobClient = storageAccount.CreateCloudBlobClient();
var container = blobClient.GetContainerReference("storagemedia");
The thing is - I am not sure how I am supposed to retrieve a particular file? I tried:
1.
CloudBlobDirectory dira = container.GetDirectoryReference("10890"); // file folder within media
var list = dira2.ListBlobs(useFlatBlobListing: true).ToList(); // Returns error saying "The requested URI does not represent any resource on the server."
However the 10890 folder within media storage exists and I can browse it with storage browser.
2.
CloudBlockBlob blobFile = container.GetBlockBlobReference("10890/filename.xls");
string text;
using (var memoryStream = new MemoryStream())
{
blobFile.DownloadToStream(memoryStream); // Throws "The specifed resource name contains invalid characters." error
var length = memoryStream.Length;
text = System.Text.Encoding.UTF8.GetString(memoryStream.ToArray());
}
Any idea how to read the file? And what am I doing wrong?
Thank You Gaurav for providing your suggestion in comment section.
Thank You nicornotto for confirming that your issue got resolved by changing the container name reference in the below statement.
var container = blobClient.GetContainerReference("storagemedia");
I want to create a Azure SDK BlobClient knowing the blob Uri. I can do it like that :
StorageSharedKeyCredential storageCredential = new StorageSharedKeyCredential("devstoreaccount1", "account key");
BlobClient bl = new BlobClient(new Uri(blobUri), storageCredential);
But I do not want to use the StorageSharedKey in this case. I want to use the connection string.
However the constructor taking a connection string as first parameter looks like this :
Is there another way to initialize the BlobClient with Blob Uri + connection string ? If not, since all I have as input is the Blob Url, is there a way to parse the Url in order to isolate the container name and the blob name ? I don't see how to identify them.
Kind of hacky solution but you can try something like this:
BlobClient blobClient = new BlobClient(new Uri("blob-uri"));
var containerName = blobClient.BlobContainerName;
var blobName = blobClient.Name;
blobClient = new BlobClient(connectionString, containerName, blobName);
I'm trying to use nuget Microsoft.Azure.CognitiveServices.Knowledge.QnAMaker to use QnAMakerClient and Knowledgebase.DownloadWithHttpMessagesAsync, but when I try to instantiate Microsoft.Azure.CognitiveServices.Knowledge.QnAMaker() the parameters are the abstract classes, so I don't know how I can use QnAMakerClient to download the contents of Body.QnaDocuments.
Microsoft.Azure.CognitiveServices.Knowledge.QnAMaker.QnAMakerClient z = new Microsoft.Azure.CognitiveServices.Knowledge.QnAMaker.QnAMakerClient(new ServiceClientCredentials(),HttpClient httpClient, bool disposeHttpClient);
var kb = z.Knowledgebase.DownloadWithHttpMessagesAsync("key", "test").Result;
Thanks for your help.
#elise You can find one example on how to download the knowledgebase here.
Essentially:
var client = new QnAMakerClient(new ApiKeyServiceClientCredentials(key)) { Endpoint = endpoint };
// Download the KB
Console.Write("Downloading KB...");
var kbData = await client.Knowledgebase.DownloadAsync(kbId, EnvironmentType.Prod);
Console.WriteLine("KB Downloaded. It has {0} QnAs.", kbData.QnaDocuments.Count);
Is it possible to download a specific block from an Azure Block Blob if you know the Block Id?
Yes, you absolutely can, here's an example of how to download the first block:
var storageAccount = CloudStorageAccount.Parse("DefaultEndpointsProtocol=https;AccountName=...;AccountKey=...;EndpointSuffix=core.windows.net");
CloudBlobClient serviceClient = storageAccount.CreateCloudBlobClient();
var container = serviceClient.GetContainerReference("containerName");
var blockBlob = container.GetBlockBlobReference("blobName");
var blocklist = await blockBlob.DownloadBlockListAsync();
var firstBlock = blocklist.First();
var memStream = new MemoryStream();
await blockBlob.DownloadRangeToStreamAsync(memStream, 0, firstBlock.Length);
string contents;
using (var streamReader = new StreamReader(memStream))
{
contents = await streamReader.ReadToEndAsync();
}
You will need a couple of packages from nuget:
Microsoft.WindowsAzure.Storage
Microsoft.WindowsAzure.Storage.Blob
You could leverage Microsoft Azure Storage SDK for getting started with Azure Blob Storage quickly. And the Azure Storage SDK is a wrapper of Blob Service REST API. From the official tutorial about Blob Service REST API, we couldn't find anything about downloading the specific block via the Block Id. In addition, you could use Get Blob to download the bytes of your blob in the specified range by specifying the offset and the length of data to download from your blob.