AWS S3 单个文件上传+获取url

框架是.NET MVC+API，下面简称WebApi了。

最开始调用AWS S3，不报错，但是始终没有办法上传成功。

开始怀疑点：

1.框架

2.方法

3.异步

4.连接数据库

但是最后调查发现是因为配置文件中的Log导致

去除下面这一段配置就可以上传成功了。

  <log4net>
    <!--定义输出到文件中-->
    <appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="D:\Log\POC\" />
      <appendToFile value="true" />
      <rollingStyle value="Date" />
      <datePattern value="yyyy\\MM\\yyyyMMdd.'txt'" />
      <StaticLogFileName value="false"/>
      <layout type="log4net.Layout.PatternLayout">
        <!--<conversionPattern value="(%file:%line) %-5level %logger [%property{NDC}] - %message%newline" />-->
        <conversionPattern value="%-5level %message%newline" />
      </layout>
    </appender>


    <!--定义日志的输出媒介，下面定义日志以四种方式输出。也可以下面的按照一种类型或其他类型输出。-->
    <root>
      <!--文件形式记录日志-->
      <appender-ref ref="LogFileAppender" />
    </root>
  </log4net>

下面是调用部分，参考AWS的GitHub项目

先是建立连接，需要先配置好AccessKey，SecretKey

以及地点RegionEndpoint，中国北京是 Amazon.RegionEndpoint.CNNorth1

连接信息如下

                                #region 连接信息
                                string awsAccessKeyId = ConfigurationManager.AppSettings["awsAccessKeyId"].ToString();
                                string awsSecretAccessKey = ConfigurationManager.AppSettings["awsSecretAccessKey"].ToString();
                                string bucketName = ConfigurationManager.AppSettings["BucketName"].ToString();
                                #endregion

                                #region 建立连接
                                //验证信息
                                AWSCredentials credentials = new BasicAWSCredentials(awsAccessKeyId, awsSecretAccessKey);
                                //配置
                                AmazonS3Config config = new AmazonS3Config()
                                {
                                    RegionEndpoint = Amazon.RegionEndpoint.CNNorth1
                                };
                                //建立连接
                                AmazonS3Client s3Client = new AmazonS3Client(credentials, config);
                                #endregion

上传部分，这里是本地文件上传
newFilePathName是本地文件路径，物理路径；
objRequest.Key是AWS S3存储tongu桶里面的名字，相当于主键，这个根据需要随意变更；
这里用的newFileName，是文件名。

                                #region 上传
                                //文件
                                PutObjectRequest objRequest = new PutObjectRequest();
                                FileStream fileStream = new FileStream(newFilePathName, FileMode.Open, FileAccess.Read);
                                objRequest.InputStream = fileStream;
                                objRequest.BucketName = bucketName;
                                objRequest.Key = newFileName;
                                //上传文件
                                PutObjectResponse res = s3Client.PutObject(objRequest);
                                #endregion

获取url部分

AWS S3示例

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. 
// SPDX-License-Identifier: MIT-0
// snippet-start:[s3.dotNET.GenPresignedURLTest]
using Amazon;
using Amazon.S3;
using Amazon.S3.Model;
using System;

namespace Amazon.DocSamples.S3
{
    class GenPresignedURLTest
    {
        private const string bucketName = "*** bucket name ***"; 
        private const string objectKey = "*** object key ***";
        // Specify how long the presigned URL lasts, in hours
        private const double timeoutDuration = 12;
        // Specify your bucket region (an example region is shown).
        private static readonly RegionEndpoint bucketRegion = RegionEndpoint.USWest2;
        private static IAmazonS3 s3Client;

        public static void Main()
        {
            s3Client = new AmazonS3Client(bucketRegion);
            string urlString = GeneratePreSignedURL(timeoutDuration);
        }
        static string GeneratePreSignedURL(double duration)
        {
            string urlString = "";
            try
            {
                GetPreSignedUrlRequest request1 = new GetPreSignedUrlRequest
                {
                    BucketName = bucketName,
                    Key = objectKey,
                    Expires = DateTime.UtcNow.AddHours(duration)
                };
                urlString = s3Client.GetPreSignedURL(request1);
            }
            catch (AmazonS3Exception e)
            {
                Console.WriteLine("Error encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            catch (Exception e)
            {
                Console.WriteLine("Unknown encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            return urlString;
        }
    }
}
// snippet-end:[s3.dotNET.GenPresignedURLTest]

项目应用的部分。

                                #region 获取
                                GetPreSignedUrlRequest urlRequest = new GetPreSignedUrlRequest
                                {
                                    BucketName = bucketName,
                                    Key = newFileName,
                                    Expires = DateTime.UtcNow.AddHours(12)
                                };
                                string urlString = s3Client.GetPreSignedURL(urlRequest);
                                #endregion

最后是引用。

第一行用来获取配置文件的，

后面Amazon开头的都是必不可少的调用S3必须的引用；

这几个引用可以通过Nuget来下载。

using System.Configuration;
using Amazon.S3;
using Amazon.S3.Model;
using Amazon.S3.Transfer;
using Amazon.Runtime;

 最后的最后就是把他们装到一个类里去了

 这里改动了一个地方，和上面不一样的地方，用了异步。

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Configuration;
using Amazon;
using Amazon.S3;
using Amazon.S3.Model;
using Amazon.S3.Transfer;
using Amazon.Runtime;
using System.Threading.Tasks;
using System.IO;

namespace XXX
{
    public class AmazonS3Upload
    {
        #region 连接信息
        static string awsAccessKeyId = ConfigurationManager.AppSettings["awsAccessKeyId"].ToString();
        static string awsSecretAccessKey = ConfigurationManager.AppSettings["awsSecretAccessKey"].ToString();
        static string bucketName = ConfigurationManager.AppSettings["BucketName"].ToString();
        #endregion

        #region 建立连接
        //验证信息
        static AWSCredentials credentials = new BasicAWSCredentials(awsAccessKeyId, awsSecretAccessKey);
        //配置
        static AmazonS3Config config = new AmazonS3Config()
        {
            RegionEndpoint = Amazon.RegionEndpoint.CNNorth1
        };
        //建立连接
        AmazonS3Client s3Client = new AmazonS3Client(credentials, config);
        #endregion

        /// <summary>
        /// 上传文件
        /// </summary>
        /// <param name="newFilePathName"></param>
        /// <param name="newFileName"></param>
        public async Task UploadAnObject(string newFilePathName, string newFileName)
        {
            try
            {
                PutObjectRequest objRequest = new PutObjectRequest();
                FileStream fileStream = new FileStream(newFilePathName, FileMode.Open, FileAccess.Read);
                objRequest.InputStream = fileStream;
                objRequest.BucketName = bucketName;
                objRequest.Key = newFileName;
                //上传文件
                PutObjectResponse res = await s3Client.PutObject(objRequest);
            }
            catch (AmazonS3Exception e)
            {
                Console.WriteLine(
                        "Error encountered ***. Message:'{0}' when writing an object"
                        , e.Message);
            }
            catch (Exception e)
            {
                Console.WriteLine(
                    "Unknown encountered on server. Message:'{0}' when writing an object"
                    , e.Message);
            }
        }

        /// <summary>
        /// 获取文件地址
        /// </summary>
        /// <param name="newFileName"></param>
        /// <returns></returns>
        public string GeneratePreSignedURL(string newFileName)
        {
            string urlString = "";
            try
            {
                GetPreSignedUrlRequest request1 = new GetPreSignedUrlRequest
                {
                    BucketName = bucketName,
                    Key = newFileName,
                    Expires = DateTime.UtcNow.AddHours(12)
                };
                urlString = s3Client.GetPreSignedURL(request1);
            }
            catch (AmazonS3Exception e)
            {
                Console.WriteLine("Error encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            catch (Exception e)
            {
                Console.WriteLine("Unknown encountered on server. Message:'{0}' when writing an object", e.Message);
            }
            return urlString;
        }
    }
}