csharp 通过.net WebAPI将Azure存储专用容器blob下载/流式传输到AngularJS

Posted 2021-05-12

using System;
using System.Configuration;
using System.IO;
using System.Threading.Tasks;
using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Blob;

namespace MyApp.Providers
{
    public class AzureProvider
    {
        public async Task<AzureBlobModel> GetAzureBlob(string containerName, string fileName)
        {
            var cloudBlockBlob = ResolveCloudBlockBlob(containerName, fileName);
            var stream = await cloudBlockBlob.OpenReadAsync();

            var blob = new AzureBlobModel()
            {
                FileName = fileName,
                FileSize = cloudBlockBlob.Properties.Length,
                Stream = stream,
                ContentType = cloudBlockBlob.Properties.ContentType
            };

            return blob;
        }

        public async Task<string> UploadStreamToAzure(string containerName, string fileName, MemoryStream stream)
        {
            var blockBlob = ResolveCloudBlockBlob(containerName, fileName);
            await blockBlob.UploadFromStreamAsync(stream);
            return fileName;
        }

        public CloudBlockBlob ResolveCloudBlockBlob(string containerName, string fileName)
        {
            var container = ResolveCloudBlobContainer(containerName);
            var blockBlob = container.GetBlockBlobReference(fileName);
            return blockBlob;
        }

        public CloudBlobContainer ResolveCloudBlobContainer(string containerName)
        {
            var storageAccount = GetCloudStorageAccount();
            var blobClient = storageAccount.CreateCloudBlobClient();
            var container = blobClient.GetContainerReference(containerName);
            return container;
        }

        private CloudStorageAccount GetCloudStorageAccount()
        {
            return CloudStorageAccount.Parse(ResolveAzureStorageConnectionString());
        }

        public string ResolveAzureStorageConnectionString()
        {
            var accountName = ConfigurationManager.AppSettings["Azure.Storage.AccountName"]; // Get account name from web.config
            var accessKey = ConfigurationManager.AppSettings["Azure.Storage.PrimaryAccessKey"]; // Get primary access key from web.config
            return String.Format("DefaultEndpointsProtocol=https;AccountName={0};AccountKey={1}", accountName, accessKey);
        }
    }
}

(function () {
    "use strict";

    angular
        .module("MyApp.Common")
        .service("AzureBlobDownloadService", AzureBlobDownloadService);

    AzureBlobDownloadService.$inject = ["$http", "$log"];
    function AzureBlobDownloadService($http, $log) {
        // Example call from an angular controller (AzureBlobDownloadService obviously needs to be injected):
        // AzureBlobDownloadService.getBlob("/api/reports/sampleReport", { fileName: "someFileName" });
        // NOTE: you should set the fileName through angular $http params instead of directly
        // putting it into the url to avoid having problems with the dot (".") character ž
        // in the url of your WebAPI call
        this.getBlob = function (url, params) {
            return $http.get(url, {
                cache: false,
                responseType: "arraybuffer",
                headers: {
                    "Content-Type": "application/octet-stream; charset=utf-8"
                },
                params: params
            }).success(function (data, status, headers) {
                var octetStreamMime = "application/octet-stream";
                headers = headers();
                var fileName = !!headers["x-filename"] ? decodeURIComponent(escape(headers["x-filename"])) : "download.pdf";
                var contentType = headers["content-type"] || octetStreamMime;

                try {
                    var blob = new Blob([data], { type: contentType });
                    saveAs(blob, fileName);
                } catch (ex) {
                    $log.error("Simulated download is not supported by your browser.");
                    $log.error(ex);
                }
            });
        }
    }
})();

using System.Web.Http;
using System.Threading.Tasks;

namespace MyApp.Controllers.API
{
    [RoutePrefix("api/reports")]
    public class ReportsController : BaseApiController
    {
        private AzureProvider _azureProvider;

        public ReportsController()
        {
            _azureProvider = new AzureProvider();
        }

        [Route("sampleReport/{fileName}")]
        public async Task<IHttpActionResult> GetSampleReport(string fileName)
        {
            var containerName = "democontainer";
            var report = await _azureProvider.GetAzureBlob(containerName, fileName);

            return AzureBlobOk(report);
        }
    }
}

using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Web.Http;
using MyApp.Models;

namespace MyApp.Infrastructure
{
    public class BaseApiController : ApiController
    {
        /// <summary>
        /// Returns HTTP status 200 (OK) when user tries to fetch private Azure blob through the backend/WebAPI.
        /// </summary>
        /// <param name="azureBlob">Azure Blob Model.</param>
        /// <returns>Action result.</returns>
        protected IHttpActionResult AzureBlobOk(AzureBlobModel azureBlob)
        {
            var response = Request.CreateResponse(HttpStatusCode.OK);
            response.Content = new StreamContent(azureBlob.Stream);
            response.Content.Headers.ContentType = new MediaTypeHeaderValue(azureBlob.ContentType);
            response.Content.Headers.Add("x-filename", azureBlob.FileName);
            response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = azureBlob.FileName;
            response.Content.Headers.ContentDisposition.Size = azureBlob.FileSize;

            return ResponseMessage(response);
        }
    }
}

using System.IO;

namespace MyApp.Models
{
    public class AzureBlobModel
    {
        public string FileName { get; set; }

        public long? FileSize { get; set; }

        public Stream Stream { get; set; }

        public string ContentType { get; set; }
    }
}