Core.Blueprint.DAL/Core.Blueprint.DAL.Infrastrcture/Proxies/ProxyBlobStorage.cs

using Azure.Storage.Blobs;
using Azure.Storage.Blobs.Models;
using Azure.Storage.Sas;
using Core.Blueprint.DAL.Infrastructure.Contracts;
using Core.Blueprint.Domain.Dtos;
using Microsoft.Extensions.Azure;
using System.Reflection.Metadata;

namespace Core.Blueprint.DAL.Infrastructure.Proxies;

public class ProxyBlobStorage : IProxyBlobStorage
{

    private readonly BlobServiceClient _blobServiceClient;
    private readonly BlobContainerClient _blobContainerClient;
    private const string TIMESTAMP_TAG_NAME = "Timestamp";
    private UserDelegationKey _blobDelegationKey;

    public ProxyBlobStorage(BlobServiceClient blobServiceClient)
    {
        _blobServiceClient = blobServiceClient;
        _blobContainerClient = blobServiceClient.GetBlobContainerClient("blueprint");
        _blobDelegationKey = _blobServiceClient.GetUserDelegationKey(DateTimeOffset.UtcNow,
                                                                    DateTimeOffset.UtcNow.AddHours(2));
    }

    public async IAsyncEnumerable<ImageUrlDto> ListAllItemsAsync()
    {
        await using (var blobs = _blobContainerClient.GetBlobsAsync().GetAsyncEnumerator())
        {
            while (await blobs.MoveNextAsync())
            {
                yield return new ImageUrlDto
                {
                    Url = _blobContainerClient.GenerateSasUri(BlobContainerSasPermissions.Read, DateTimeOffset.UtcNow.AddMinutes(5))
                };
            }
        }
    }

    public async Task<ImageUrlDto> GetFirstImageUrlAsync()
    {
        await using (var blob = _blobContainerClient.GetBlobsAsync().GetAsyncEnumerator())
        {
            System.Console.WriteLine(_blobContainerClient.Uri.ToString());
            await blob.MoveNextAsync();

            var blobClient = _blobContainerClient.GetBlobClient(blob.Current.Name);

            var sasBuilder = new BlobSasBuilder()
            {
                BlobContainerName = blobClient.BlobContainerName,
                BlobName = blobClient.Name,
                Resource = "b",
                StartsOn = DateTimeOffset.UtcNow,
                ExpiresOn = DateTimeOffset.UtcNow.AddMinutes(5),
            };
            sasBuilder.SetPermissions(BlobAccountSasPermissions.Read);

            var blobUriBuilder = new BlobUriBuilder(blobClient.Uri){
                Sas = sasBuilder.ToSasQueryParameters(_blobDelegationKey, _blobServiceClient.AccountName)
            };

            var uri = blobUriBuilder.ToUri();
            System.Console.WriteLine(uri);
            return new ImageUrlDto { Url = uri };
        }
    }

    public async Task<ImageUrlDto> GetUploadUrl()
    {
        await using (var blobs = _blobContainerClient.GetBlobsAsync().GetAsyncEnumerator())
        {
            await blobs.MoveNextAsync();

            var blobClient = _blobContainerClient.GetBlobClient(blobs.Current.Name);

            var sasBuilder = new BlobSasBuilder(){
                BlobContainerName = blobClient.BlobContainerName,
                BlobName = blobClient.Name,
                Resource = "b",
                StartsOn = DateTimeOffset.UtcNow,
                ExpiresOn = DateTimeOffset.UtcNow.AddMinutes(5),
            };
            sasBuilder.SetPermissions(BlobAccountSasPermissions.Read);

            var blobUriBuilder = new BlobUriBuilder(blobClient.Uri){
                Sas = sasBuilder.ToSasQueryParameters(_blobDelegationKey, _blobServiceClient.AccountName)
            };

            var uri = blobUriBuilder.ToUri();
            return new ImageUrlDto { Url = uri };
        }
    }
}