使用 IronOcr 在 AWS Lambda 上讀取文件

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這篇操作指南將指導您完成使用 IronOCR 設置 AWS Lambda 函數的步驟。透過本指南，您將學會如何設置IronOCR並從S3 Bucket讀取文件。

1. 使用容器範本建立 AWS Lambda

要讓 IronOcr 正常運作，必須在機器上安裝某些依賴項 —— 為了確保這些依賴項被安裝，Lambda 函數必須被容器化。

使用 Visual Studio，創建容器化的 AWS Lambda 是一個簡單的過程：只需安裝AWS 工具包 for Visual Studio，選擇 AWS Lambda C# 模板，接著選擇 Container Image 藍圖，然後選擇“完成”。

2. 添加套件依賴性

將項目的 dockerfile 進行以下修改：請提供內容以進行翻譯。

設置為 dotnet:5 或 dotnet:6 用於 .NET 5/6

FROM public.ecr.aws/lambda/dotnet:7

WORKDIR /var/task

運行 yum update -y

RUN yum install -y amazon-linux-extras

RUN amazon-linux-extras install epel -y

RUN yum install -y libgdiplus

將 "bin/Release/lambda-publish" 複製至。請提供內容以進行翻譯。

3. 安裝 IronOcr 和 IronOcr.Linux NuGet 套件

要在 Visual Studio 中安裝 IronOcr 和 IronOcr.Linux 套件：

前往 專案 > 管理 NuGet 套件...
選擇瀏覽，然後搜索IronOcr和IronOcr.Linux。
選擇套件並安裝。

4. 修改 FunctionHandler 代碼

此範例將從 S3 桶中檢索圖像並讀取它。它使用 SixLabors 的 Image 類別來將圖像加載到 IronOcr 中。為了使範例正常運作，必須設置一個S3桶。SixLabors.ImageSharp必須安裝NuGet套件。

:path=/static-assets/ocr/content-code-examples/how-to/iron-ocr-aws-lambda-sample.cs

using Amazon;
using Amazon.Lambda.Core;
using Amazon.S3;
using Amazon.S3.Model;
using SixLabors.ImageSharp;
using IronOcr;

// Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class.
[assembly: LambdaSerializer(typeof(Amazon.Lambda.Serialization.SystemTextJson.DefaultLambdaJsonSerializer))]

namespace IronOcrAWSLambda;

public class Function
{
	private readonly IAmazonS3 _s3Client;
	private readonly string accessKey;
	private readonly string secretKey;

	public Function()
	{
		accessKey = "ACCESS-KEY";
		secretKey = "SECRET-KEY";
		_s3Client = new AmazonS3Client(accessKey, secretKey);
	}
	public async Task<string> FunctionHandler(string input, ILambdaContext context)
	{
		IronOcr.License.LicenseKey = "IRONOCR-LICENSE-KEY";
		string bucketName = "S3-BUCKET-NAME";

		var getObjectRequest = new GetObjectRequest
		{
			BucketName = bucketName,
			Key = input,
		};

		using (GetObjectResponse response = await _s3Client.GetObjectAsync(getObjectRequest))
		{
			// Read the content of the object
			using (Stream responseStream = response.ResponseStream)
			{
				Console.WriteLine("Reading image from S3");
				Image image = Image.Load(responseStream);

				Console.WriteLine("Reading image with IronOCR");
				IronTesseract ironTesseract = new IronTesseract();
				OcrInput ocrInput = new OcrInput(image);
				OcrResult result = ironTesseract.Read(ocrInput);

				return result.Text;
			}
		}
	}
}

Imports Amazon
Imports Amazon.Lambda.Core
Imports Amazon.S3
Imports Amazon.S3.Model
Imports SixLabors.ImageSharp
Imports IronOcr

' Assembly attribute to enable the Lambda function's JSON input to be converted into a .NET class.
<Assembly: LambdaSerializer(GetType(Amazon.Lambda.Serialization.SystemTextJson.DefaultLambdaJsonSerializer))>

Namespace IronOcrAWSLambda

	Public Class [Function]
		Private ReadOnly _s3Client As IAmazonS3
		Private ReadOnly accessKey As String
		Private ReadOnly secretKey As String

		Public Sub New()
			accessKey = "ACCESS-KEY"
			secretKey = "SECRET-KEY"
			_s3Client = New AmazonS3Client(accessKey, secretKey)
		End Sub
		Public Async Function FunctionHandler(ByVal input As String, ByVal context As ILambdaContext) As Task(Of String)
			IronOcr.License.LicenseKey = "IRONOCR-LICENSE-KEY"
			Dim bucketName As String = "S3-BUCKET-NAME"

			Dim getObjectRequest As New GetObjectRequest With {
				.BucketName = bucketName,
				.Key = input
			}

			Using response As GetObjectResponse = Await _s3Client.GetObjectAsync(getObjectRequest)
				' Read the content of the object
				Using responseStream As Stream = response.ResponseStream
					Console.WriteLine("Reading image from S3")
					Dim image As Image = System.Drawing.Image.Load(responseStream)

					Console.WriteLine("Reading image with IronOCR")
					Dim ironTesseract As New IronTesseract()
					Dim ocrInput As New OcrInput(image)
					Dim result As OcrResult = ironTesseract.Read(ocrInput)

					Return result.Text
				End Using
			End Using
		End Function
	End Class
End Namespace

VB C#