Azure vs GCP part 5: Storage (Azure)

Any application needs some place to store data, such as SQL, NoSQL, Storage etc. In this article, I look into Azure Storage service, and I write separate article for GCP Storage.

Azure Storage

Azure Storage is linked under Azure Storage Account. So I need to create account first, but I need to understanding what options are available.

Azure Storage Types

Azure offers several types of storage and services.

• Blob: Store files such as image, documents, or VHD for VM. It provides REST endpoint and SDKs for many langauges.
• Files: Highly available network share which you can access via SMB. It also provides REST endpoint.
• Disk: Works as native file system for VM.
• Tables: Tabular data storage.
• Queue: Queue objects.

Oh first three sounds similar? Yes it does. So there is good matrix to understand the differences.

Comparison: Files and Blobs
Comparison: Files and Disks

In this article, as I need storage from Web Application point of view, I use blob storage.

Account Options

In addition to Storage Options, I need to select account option.

• General purpose V2 (GPV2)
• General purpose V1 (GPV1)
• Blob storage

You can read the detail here but simply put, GPV2 = GPV1 + Blob storage. Checkout Recommendation section for more detail which account you want to use.

Performance

Azure Storage offers two storage types.

• Premium: SSD base. Good for VMs.
• Standard: Normal HDD base.

It also offer two access tiers.

• Hot: Good for frequently accessed storage. Lower access cost.
• Cold: Good for fewer accessed storage. Lower storage cost.

Other things

There are many more things you should know about the service, such as security, redundancy, access methods. You can find those information at Planning for an Azure Files deployment

It also provides Azure platform level features same as other services, such as:

• ACL
• Firewall
• Custom DNS
• Monitoring
• CDN
• Reporting
• Integrate with other services, etc.

Integration is interesting topic as it works with Azure Search, Event Grid, etc. I keep this for the future topic.

Azure Blob Storage

See here for detail. I just share structure concept here.

Blob service has following structure.

• Account: Storage Account which explained above.
• Container: Works as grouping or like folder.
• Blob: Actual content.

Let's code!!

Okay, enough talk!! Let's write code as that's what I am interested in.

1. First of all, I create storage account. There are several ways to create it, but I use CLI in portal. Go to Azure Portal and select "Cloud Shell".

2. Run the code to create account. I provision my account in East US, with Geo-redundant, with normal storage as Hot tier and https access only. Second command displays connection string which I use in the application.

az storage account create -n cloudcomparestorage -g CloudCompareRG --kind storageV2 --sku Standard_GRS --access-tier Hot --location eastus --https-only
az storage account show-connection-string -n cloudcomparestorage -g cloudcomparerg

3. Create a images container for blob. I set it public accessible.

az storage container create --name images --public-access blob --account-name cloudcomparestorage

4. As blob storage is ready, open Visual Studio and create new project. Select "ASP.NET Core Web Application" and create it.

5. Select "Web API" and click OK.

6. Add "WindowsAzure.Storage" NuGet package.

7. Rename existing "ValueController.cs" to "StorageController.cs", then paste the code. Replace the storage key at line 20.

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Blob;
using System;
using System.Threading.Tasks;

namespace Storage.Controllers
{
    [Route("api/[controller]")]
    public class StorageController : Controller
    {
        static CloudBlobClient blobClient;
        const string blobContainerName = "images";
        static CloudBlobContainer blobContainer;

        public StorageController()
        {
            CloudStorageAccount storageAccount = 
                CloudStorageAccount.Parse("<Your connection string>");

            // Create a blob client for interacting with the blob service.
            blobClient = storageAccount.CreateCloudBlobClient();
            blobContainer = blobClient.GetContainerReference(blobContainerName);
        }

        // GET api/storage/filename
        [HttpGet("{filename}")]
        public async Task<IActionResult> Get(string filename)
        {
            try
            {
                CloudBlockBlob blob = blobContainer.GetBlockBlobReference(filename);
                var image = await blob.OpenReadAsync();
                return new ObjectResult(image);
            }
            catch (Exception ex)
            {
                return NotFound();
            }
        }

        // POST api/storage
        [HttpPost]
        public async Task Post(IFormFile file)
        {
            try
            {
                CloudBlockBlob blob = blobContainer.GetBlockBlobReference(file.FileName);
                await blob.UploadFromStreamAsync(file.OpenReadStream());
            }
            catch (Exception ex)
            {               
            }
        }

        // DELETE api/storage/filename
        [HttpDelete("{filename}")]
        public async Task<IActionResult> Delete(string filename)
        {
            try
            {
                CloudBlockBlob blob = blobContainer.GetBlockBlobReference(filename);
                await blob.DeleteAsync();
                return Ok();
            }
            catch (Exception ex)
            {
                return NotFound();
            }
        }
    }
}

Test it

1. Hit F5 to debug the applicaiton. Check the address and port.

2. Open Postman and select "POST" as verb, enter the endpoint address, then click "Body".

3. Select "File" from key dropdown.

4. Enter "file" to key and choose any image file from your local PC and hit "Send". I selected "apple-touch-icon.png".

5. Switch verb from "POST" to "GET", then add "/ to the address.

6. Go to Azure Portal Cloud shell and run the command to confirm that there is a blob file.

az storage blob list --account-name cloudcomparestorage -c images --query '[].{name:name}'

7. As I set the blob public access, you can also access to the image via browser from anywhere.

https://.blob.core.windows.net//

8. In Postman, change verb to "DELETE" and hit send.

Deploy to each platform

Now the code works. Let's deploy to Azure Web Apps and GCP App Engine. See part 1 for how to detail.

Azure Web Apps

Yes it works as expected. Nothing to write here. But I used Windows version.

GCP App Engine

This also works as expected. Though storage still sits on Azure, web api lives in GCP :)

Summary

When I develop a Web API, it's easy enough with SDK, and I don't have to care where the storage is, and how they are backup, scale, or secured. But when I think about service plans and options, there are so many thing to consider. However, with several clicks, I can tweak performance, resiliency, security, and so on :)

I bet GCP should have similar capability but let's see it in the next article.

Ken