{"id":5391,"date":"2017-09-19T19:46:46","date_gmt":"2017-09-19T19:46:46","guid":{"rendered":"http:\/\/putridparrot.com\/blog\/?p=5391"},"modified":"2017-09-19T19:46:46","modified_gmt":"2017-09-19T19:46:46","slug":"using-azure-blob-storage","status":"publish","type":"post","link":"https:\/\/putridparrot.com\/blog\/using-azure-blob-storage\/","title":{"rendered":"Using Azure Blob Storage"},"content":{"rendered":"

Blob storage has the concept of containers (which can be thought of as directories) and those containers can contain BLOB’s. Containers cannot<\/strong> contain containers and hence differ from a file system in structure. <\/p>\n

Containers can be private or allow anonymous read access to BLOBs only or allow anonymous read access for containers and BLOBs.<\/p>\n

In the Azure Portal, if you haven’t already got one set up, create a storage account then create a Blob service. Next create a container, mine’s named test<\/em>. Next, upload a file, I’ve uploaded Hello World.txt<\/em> which as you imagine simply has the line Hello World<\/em> within it.<\/p>\n

When you create a Blob service you’re assigned an endpoint name, along the lines of https:\/\/<storage account>.blob.core.winodws.net\/<\/p>\n

When we add containers, these get the URL https:\/\/<storage account>.blob.core.windows.net\/<container name><\/em> and files get the URL https:\/\/<storage account>.blob.core.windows.net\/<container name>\/<file name><\/em><\/p>\n

A comprehensive document on using .NET to interact with the Blob storage can be found at Get started with Azure Blob storage using .NET<\/a>. <\/p>\n

Reading a Blob<\/strong><\/p>\n

Here’s some code to read our uploaded Hello World.txt file<\/p>\n

Firstly we need to use NuGet to add package WindowsAzure.Storage and Microsoft.WindowsAzure.ConfigurationManager.<\/em><\/p>\n

\r\nusing Microsoft.Azure;\r\nusing Microsoft.WindowsAzure.Storage;\r\n\r\nprivate static void ReadBlob()\r\n{\r\n   var storageAccount = CloudStorageAccount.Parse(\r\n      CloudConfigurationManager.GetSetting(\r\n         "StorageConnectionString"));\r\n\r\n   var blobClient = storageAccount.CreateCloudBlobClient();\r\n   var container = blobClient.GetContainerReference("test");\r\n   var blob = container.GetBlockBlobReference("Hello World.txt");\r\n   var contents = blob.DownloadText();\r\n\r\n   Console.WriteLine(contents);\r\n}\r\n<\/pre>\n
In the example our file is a text file, but we can also access the blob as a stream using DownloadToStream (plus there’s a whole bunch of other methods for accessing the blobs).<\/p>\n
Writing a Blob<\/strong><\/p>\n
We can write blobs pretty easily also<\/p>\n
\r\npublic static void WriteBlob()\r\n{\r\n   var storageAccount = CloudStorageAccount.Parse(\r\n      CloudConfigurationManager.GetSetting(\r\n         "StorageConnectionString"));\r\n\r\n   var blobClient = storageAccount.CreateCloudBlobClient();\r\n\r\n   var container = blobClient.GetContainerReference("test");\r\n\r\n   var blob = container.GetBlockBlobReference("new.txt");\r\n   blob.UploadFromFile("new.txt");\r\n}\r\n<\/pre>\n
In this example, as you’ll see, we still do the standard, connect to cloud via the blob client, get a reference to the container we want to interact with, but next we get a blob to a file (in this case new.txt didn’t exist) and then upload or write from a stream to blob storage. If “new.txt” does exist in the blob storage it’ll simply be overwritten.<\/p>\n
Deleting a Blob<\/strong><\/p>\n
We’ve looked at Creation\/Update of blobs and Retrieval or them so let’s complete CRUD operations on blobs with delete<\/p>\n
\r\npublic static void DeleteBlob()\r\n{\r\n   var storageAccount = CloudStorageAccount.Parse(\r\n      CloudConfigurationManager.GetSetting(\r\n         "StorageConnectionString"));\r\n\r\n   var blobClient = storageAccount.CreateCloudBlobClient();\r\n\r\n   var container = blobClient.GetContainerReference("test");\r\n\r\n   var blob = container.GetBlockBlobReference("new.txt");\r\n   blob.DeleteIfExists();\r\n}\r\n<\/pre>\n
References<\/strong><\/p>\n
Along with the standard CRUD type operations we can carry out actions on containers, list blobs etc.<\/p>\n
See Get started with Azure Blob storage using .NET<\/a> for more information.<\/p>\n
The Blob Service REST API<\/a> lists the REST API’s if you’d prefer to bypass the Microsoft libraries for accessing the Blobs (or need to implement in a different language).<\/p>\n","protected":false},"excerpt":{"rendered":"
Blob storage has the concept of containers (which can be thought of as directories) and those containers can contain BLOB’s. Containers cannot contain containers and hence differ from a file system in structure. Containers can be private or allow anonymous read access to BLOBs only or allow anonymous read access for containers and BLOBs. In […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[96],"tags":[],"class_list":["post-5391","post","type-post","status-publish","format-standard","hentry","category-azure-2"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/posts\/5391","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/comments?post=5391"}],"version-history":[{"count":9,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/posts\/5391\/revisions"}],"predecessor-version":[{"id":5407,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/posts\/5391\/revisions\/5407"}],"wp:attachment":[{"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/media?parent=5391"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/categories?post=5391"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/putridparrot.com\/blog\/wp-json\/wp\/v2\/tags?post=5391"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}