AWS LambdaとS3でアップロード画像を自動リサイズ・WebP変換する

// dependencies
import { S3Client, GetObjectCommand, PutObjectCommand } from '@aws-sdk/client-s3';
 
import { Readable } from 'stream';
 
import sharp from 'sharp';
import util from 'util';
 
 
// create S3 client
const s3 = new S3Client({region: 'us-east-1'});
 
// define the handler function
export const handler = async (event, context) => {
 
// Read options from the event parameter and get the source bucket
console.log("Reading options from event:\n", util.inspect(event, {depth: 5}));
  const srcBucket = event.Records[0].s3.bucket.name;
  
// Object key may have spaces or unicode non-ASCII characters
const srcKey    = decodeURIComponent(event.Records[0].s3.object.key.replace(/\+/g, " "));
const dstBucket = srcBucket + "-resized";
const dstKey    = "resized-" + srcKey;
 
// Infer the image type from the file suffix
const typeMatch = srcKey.match(/\.([^.]*)$/);
if (!typeMatch) {
  console.log("Could not determine the image type.");
  return;
}
 
// Check that the image type is supported
const imageType = typeMatch[1].toLowerCase();
if (imageType != "jpg" && imageType != "png") {
  console.log(`Unsupported image type: ${imageType}`);
  return;
}
 
// Get the image from the source bucket. GetObjectCommand returns a stream.
try {
  const params = {
    Bucket: srcBucket,
    Key: srcKey
  };
  var response = await s3.send(new GetObjectCommand(params));
  var stream = response.Body;
  
// Convert stream to buffer to pass to sharp resize function.
  if (stream instanceof Readable) {
    var content_buffer = Buffer.concat(await stream.toArray());
    
  } else {
    throw new Error('Unknown object stream type');
  }
 
 
} catch (error) {
  console.log(error);
  return;
}
 
  
// set thumbnail width. Resize will set the height automatically to maintain aspect ratio.
const width  = 200;
 
// Use the sharp module to resize the image and save in a buffer.
try {    
  var output_buffer = await sharp(content_buffer).resize(width).toBuffer();
 
} catch (error) {
  console.log(error);
  return;
}
 
// Upload the thumbnail image to the destination bucket
try {
  const destparams = {
    Bucket: dstBucket,
    Key: dstKey,
    Body: output_buffer,
    ContentType: "image"
  };
 
  const putResult = await s3.send(new PutObjectCommand(destparams));
 
  } catch (error) {
    console.log(error);
    return;
  }
 
  console.log('Successfully resized ' + srcBucket + '/' + srcKey +
    ' and uploaded to ' + dstBucket + '/' + dstKey);
  };

// dependencies
import {
  S3Client,
  GetObjectCommand,
  PutObjectCommand,
} from "@aws-sdk/client-s3";
 
import { Readable } from "stream";
 
import sharp from "sharp";
 
// create S3 client
const s3 = new S3Client({ region: "ap-northeast-2" });
 
// define the handler function
export const handler = async (event, context) => {
  const srcBucket = event.Records[0].s3.bucket.name;
  const srcKey = decodeURIComponent(
    event.Records[0].s3.object.key.replace(/\+/g, " ")
  );
  const dstBucket = "resized-image-bucket-prome"; // 리사이즈된 이미지를 저장할 버킷 이름
  const filename = srcKey.split("/").pop(); // 파일명만 추출
  const dstKey = `${filename.replace(/\.[^.]+$/, ".webp")}`; 
 
  const typeMatch = srcKey.match(/\.([^.]*)$/);
  if (!typeMatch) {
    return;
  }
 
  const imageType = typeMatch[1].toLowerCase();
 
  // WebP 파일은 변환 없이 그대로 복사
  if (imageType === "webp") {
    try {
      const params = {
        Bucket: srcBucket,
        Key: srcKey,
      };
      var response = await s3.send(new GetObjectCommand(params));
      var stream = response.Body;
 
      if (stream instanceof Readable) {
        var content_buffer = Buffer.concat(await stream.toArray());
      } else {
        throw new Error("알 수 없는 객체 스트림 타입입니다");
      }
 
      const destparams = {
        Bucket: dstBucket,
        Key: dstKey,
        Body: content_buffer,
        ContentType: "image/webp",
      };
 
      await s3.send(new PutObjectCommand(destparams));
      return;
    } catch (error) {
      return;
    }
  }
 
  try {
    const params = {
      Bucket: srcBucket,
      Key: srcKey,
    };
    var response = await s3.send(new GetObjectCommand(params));
    var stream = response.Body;
 
    if (stream instanceof Readable) {
      var content_buffer = Buffer.concat(await stream.toArray());
    } else {
      throw new Error("알 수 없는 객체 스트림 타입입니다");
    }
  } catch (error) {
    return;
  }
 
  const width = 600;
  const height = 600;
 
  try {
    let sharpInstance = sharp(content_buffer, {
      animated: true, // 애니메이션 GIF 지원
      pages: -1, // 모든 프레임 처리
    }).resize(width, height, {
      fit: sharp.fit.inside,
    });
 
    var output_buffer = await sharpInstance
      .webp({
        lossless: false,
        animated: true, // 애니메이션 보존
      })
      .toBuffer();
  } catch (error) {
    return;
  }
 
  try {
    const destparams = {
      Bucket: dstBucket,
      Key: dstKey,
      Body: output_buffer,
      ContentType: "image/webp",
    };
 
    await s3.send(new PutObjectCommand(destparams));
  } catch (error) {
    return;
  }
};