Create PDF document in AWS Lambda

29 Jul 20268 minutes to read

The .NET PDF library is used to create, read, and edit PDF documents programmatically without the dependency of Adobe Acrobat. Using this library, you can open and save PDF documents in AWS Lambda.

Prerequisites

  • An active Amazon Web Services (AWS) account is required. If you don’t have one, please create an account before starting.
  • Download and install the AWS Toolkit for Visual Studio from this link. You can install the toolkit from the Extensions > Manage Extensions option in Visual Studio.
  • Visual Studio 2022 with the AWS development workload.
  • An active Syncfusion license. If you do not have one, request a free 30-day trial at https://www.syncfusion.com/sales/communitylicense.

Steps to create a PDF document in AWS Lambda

Step 1: Create a new AWS Lambda project as follows.
AWS Lambda project

Step 2: Select Blueprint as Empty Function and click Finish.
Select Blueprint as Empty Function

Step 3: Install the Syncfusion.Pdf.Imaging.Net.Core NuGet package as a reference to your project from NuGet.org.
Install NuGet package

Step 4: Register the Syncfusion® license key. A trial watermark is added to every page of the generated PDF until a valid key is registered. Include the license key in Function.cs before initializing any Syncfusion® component:

using6Syncfusion.Licensing;

public class Function
{
    public string FunctionHandler(string input)
    {
        // Register the Syncfusion license
        Syncfusion.Licensing.SyncfusionLicenseProvider.RegisterLicense("YOUR LICENSE KEY");

        // ... rest of the function body ...
    }
}

Replace "YOUR LICENSE KEY" with the license key associated with your Syncfusion® account. If you do not have a license key, you can request a free 30-day trial or apply for a Community License from the Syncfusion® website. For more information about registering a license key in your application, refer to the Syncfusion® Licensing Documentation.

Step 5: Create a folder and copy the required data files and include the files in the project.
Create a folder

Step 6: Set the copy to output directory to Copy if newer to all the data files.
Property change for data files

Step 7: Include the following namespaces in the Function.cs file.

using Syncfusion.Pdf;
using Syncfusion.Pdf.Graphics;
using Syncfusion.Drawing;
using Syncfusion.Pdf.Parsing;
using Syncfusion.Pdf.Grid;

Step 8: Add the following code in Function.cs to open the PDF document and update in AWS Lambda.

string filePath = Path.GetFullPath(@"Data/Input.pdf");
//Open an existing PDF document.
using (FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read))
{
    PdfLoadedDocument document = new PdfLoadedDocument(stream);

    //Get the first page from a document.
    PdfLoadedPage page = document.Pages[0] as PdfLoadedPage;

    //Create PDF graphics for the page.
    PdfGraphics graphics = page.Graphics;

    //Create a PdfGrid.
    PdfGrid pdfGrid = new PdfGrid();
    //Add values to the list.
    List<object> data = new List<object>();
    data.Add(new { Product_ID = "1001", Product_Name = "Bicycle", Price = "10,000" });
    data.Add(new { Product_ID = "1002", Product_Name = "Head Light", Price = "3,000" });
    data.Add(new { Product_ID = "1003", Product_Name = "Break wire", Price = "1,500" });
            
    //Assign data source.
    pdfGrid.DataSource = data;

    //Apply built-in table style.
    pdfGrid.ApplyBuiltinStyle(PdfGridBuiltinStyle.GridTable4Accent3);

    //Draw the grid to the page of PDF document.
    pdfGrid.Draw(graphics, new RectangleF(40, 400, page.Size.Width - 80, 0));

    //Save the document into stream.
    MemoryStream memoryStream = new MemoryStream();
    document.Save(memoryStream);
    //Close the document.
    document.Close(true);
    //return the stream as base64 string
    return Convert.ToBase64String(memoryStream.ToArray());
}

NOTE

The function returns the PDF as a base64-encoded string. When the Lambda is invoked synchronously, AWS wraps the return value in a JSON string, so the caller receives a JSON-quoted base64 string (e.g., "JVBERi0xLjQK..."). Strip the surrounding quotes before calling Convert.FromBase64String in the caller.

Step 9: Right-click the project and select Publish to AWS Lambda.
Publish to AWS Lambda

Step 10: Add the AWS profile in the Upload Lambda Function Window. After creating the profile, Choose Create new function or Re-deploy to the existing Lambda function to publish. Then, click Next.
Upload Lambda Function

Step 11: In the Advanced Function Details window, specify the Role Name based on AWS Managed policy. And edit the memory size and Timeout as maximum in Basic settings of the AWS Lambda function. Then, click Upload to deploy your application.
Advance Function Details

Step 12: See the published Lambda function in the AWS console after deploying the application.
After deploying the application

Steps to post the request to AWS Lambda

Follow these steps to submit a request to the AWS Lambda function.

Step 1: Create a new console project.
Create a console project

Step 2: Install the following NuGet packages in your application from NuGet.org.

Install Nuget Package

Install Nuget Package

Install Nuget Package

Step 3: Include the following namespaces in Program.cs file.

using Amazon;
using Amazon.Lambda;
using Amazon.Lambda.Model;
using Newtonsoft.Json;
using System.IO;

Step 4: Add the following code sample in Program.cs to invoke the published AWS Lambda function using the function name and access keys.

//Create a new AmazonLambdaClient
AmazonLambdaClient client = new AmazonLambdaClient("awsaccessKeyID", "awsSecreteAccessKey", RegionEndpoint.USEast1);
//Create new InvokeRequest with published function name.
InvokeRequest invoke = new InvokeRequest
{
    FunctionName = "MyNewFunction", //Add your lambda function name here
    InvocationType = InvocationType.RequestResponse,
    Payload = "\"Test\""
};
//Get the InvokeResponse from client InvokeRequest
InvokeResponse response = await client.InvokeAsync(invoke);
//Read the response stream
var stream = new StreamReader(response.Payload);
//Deserialize the response stream
JsonReader reader = new JsonTextReader(stream);
JsonSerializer serializer = new JsonSerializer();
var responseText = serializer.Deserialize(reader);

//Convert Base64String into byte array
byte[] bytes = Convert.FromBase64String(responseText.ToString());

//Write the byte array into a file
FileStream fileStream = new FileStream("Sample.pdf", FileMode.Create);
fileStream.Write(bytes, 0, bytes.Length);
fileStream.Flush();
fileStream.Dispose();

System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo() { FileName = "Sample.pdf", UseShellExecute = true });

By executing the program, you will get the PDF document as follows.

Open and save a PDF document in AWS Lambda

Users can download the console application and AWS Lambda project from GitHub.

Click here to explore the rich set of Syncfusion® PDF library features.

An online sample link to create a PDF document.

Next steps