Open document from AWS S3

20 Jan 20247 minutes to read

To load a document from AWS S3 in a Document Editor, you can follow the steps below

Step 1: Create a Simple Document Editor Sample in ASP.NET Core

Start by following the steps provided in this link to create a simple Document Editor sample in ASP.NET Core. This will give you a basic setup of the Document Editor component.

Step 2: Modify the DocumentEditorController.cs File in the Web Service Project

• Open the DocumentEditorController.cs file in your web service project.

• Import the required namespaces at the top of the file:

using System.IO;
using Amazon;
using Amazon.S3;
using Amazon.S3.Model;

• Add the following private fields and constructor parameters to the DocumentEditorController class, In the constructor, assign the values from the configuration to the corresponding fields

private IConfiguration _configuration;
public readonly string _accessKey;
public readonly string _secretKey;
public readonly string _bucketName;

public DocumentEditorController(IWebHostEnvironment hostingEnvironment, IMemoryCache cache, IConfiguration configuration)
{
  _hostingEnvironment = hostingEnvironment;
  _cache = cache;
  _configuration = configuration;
  _accessKey = _configuration.GetValue<string>("AccessKey");
  _secretKey = _configuration.GetValue<string>("SecretKey");
  _bucketName = _configuration.GetValue<string>("BucketName");
}

• Create the LoadFromS3() method to load the document from AWS S3.

[AcceptVerbs("Post")]
[HttpPost]
[EnableCors("AllowAllOrigins")]
[Route("LoadFromS3")]
//Post action for Loading the documents

public async Task<string> LoadFromS3([FromBody] Dictionary<string, string> onObject)
{
  MemoryStream stream = new MemoryStream();

  if (jsonObject == null && !jsonObject.ContainsKey("documentName"))
  {
     return null;
  }
  RegionEndpoint bucketRegion = RegionEndpoint.USEast1;

  // Configure the AWS SDK with your access credentials and other settings
  var s3Client = new AmazonS3Client(_accessKey, _secretKey, bucketRegion);
      
  string documentName = jsonObject["documentName"];
      
  // Specify the document name or retrieve it from a different source
  var response = await s3Client.GetObjectAsync(_bucketName, documentName);
      
  Stream responseStream = response.ResponseStream;
  responseStream.CopyTo(stream);
  stream.Seek(0, SeekOrigin.Begin);
  WordDocument document = WordDocument.Load(stream, FormatType.Docx);
  string json = Newtonsoft.Json.JsonConvert.SerializeObject(document);
  document.Dispose();
  stream.Close();
  return json;
}

• Open the appsettings.json file in your web service project, Add the following lines below the existing "AllowedHosts" configuration

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": "*",
  "AccessKey": "Your Access Key from AWS S3",
  "SecretKey": "Your Secret Key from AWS S3",
  "BucketName": "Your Bucket name from AWS S3"
}

NOTE

Replace Your Access Key from AWS S3, Your Secret Key from AWS S3, and Your Bucket name from AWS S3 with your actual AWS access key, secret key and bucket name

Step 3: Modify the Index.cshtml File in the Document Editor sample

In the client-side, the document is returned from the web service is opening using open method.

CSHTML

<ejs-button id="load">Open Document From AWS S3 Bucket</ejs-button>
<ejs-documenteditorcontainer id="container"></ejs-documenteditorcontainer>
<script>
    var documenteditor;
    document.addEventListener('DOMContentLoaded', function () {
        var documenteditorElement = document.getElementById("container");        
        container = documenteditorElement.ej2_instances[0];
        document.getElementById('load').addEventListener('click', function () {
            fetch(
                window.baseurl + 'api/documenteditor/LoadFromS3',
                {
                    method: 'Post',
                    headers: { 'Content-Type': 'application/json;charset=UTF-8' },
                    body: JSON.stringify({ documentName: 'Getting Started.docx' })
                }
            )
                .then(response => {
                    if (response.status === 200 || response.status === 304) {
                        return response.json(); // Return the Promise
                    } else {
                        throw new Error('Error loading data');
                    }
                })
                .then(json => {
                    container.documentEditor.open(JSON.stringify(json));
                })
                .catch(error => {
                    console.error(error);
                });
        });
    }); 
</script>

Document-editor.cs

public ActionResult Default()
{
    return View();
}

NOTE

The AWSSDK.S3 NuGet package must be installed in your application to use the previous code example.