Add the functionality to request the image metadata

source/image-handler/image-handler.ts

@@ -71,13 +71,27 @@ export class ImageHandler {
   /**
    * Main method for processing image requests and outputting modified images.
    * @param imageRequestInfo An image request.
-   * @returns Processed and modified image encoded as base64 string.
+   * @returns Processed and modified image encoded as base64 string. or json object if outputFormat is JSON
    */
   async process(imageRequestInfo: ImageRequestInfo): Promise<string> {
     const { originalImage, edits } = imageRequestInfo;
     const options = { failOnError: false, animated: imageRequestInfo.contentType === ContentTypes.GIF };
     let base64EncodedImage = "";
 
+    if (imageRequestInfo.outputFormat === ImageFormatTypes.JSON) {
+      const metadata = await sharp(originalImage, options).metadata();
+
+      const filteredMetadata = Object.keys(metadata).reduce((acc, key) => {
+          if (!Buffer.isBuffer(metadata[key])) {
+              acc[key] = metadata[key];
+          }
+          return acc;
+      }, {});
+
+      return JSON.stringify(filteredMetadata);
+
+    }
+
     // Apply edits if specified
     if (edits && Object.keys(edits).length) {
       // convert image to Sharp object

source/image-handler/image-request.ts

@@ -69,9 +69,12 @@ export class ImageRequest {
         ImageFormatTypes.TIFF,
         ImageFormatTypes.HEIF,
         ImageFormatTypes.GIF,
+        ImageFormatTypes.JSON,
       ];
 
-      imageRequestInfo.contentType = `image/${imageRequestInfo.outputFormat}`;
+
+      imageRequestInfo.contentType = imageRequestInfo.outputFormat ===  ImageFormatTypes.JSON? 'application/json' : `image/${imageRequestInfo.outputFormat}`;
+
       if (
         requestType.includes(imageRequestInfo.requestType) &&
         acceptedValues.includes(imageRequestInfo.outputFormat)

source/image-handler/index.ts

@@ -9,7 +9,7 @@ import { getOptions } from "../solution-utils/get-options";
 import { isNullOrWhiteSpace } from "../solution-utils/helpers";
 import { ImageHandler } from "./image-handler";
 import { ImageRequest } from "./image-request";
-import { Headers, ImageHandlerEvent, ImageHandlerExecutionResult, StatusCodes } from "./lib";
+import { Headers, ImageFormatTypes, ImageHandlerEvent, ImageHandlerExecutionResult, StatusCodes } from "./lib";
 import { SecretProvider } from "./secret-provider";
 
 const awsSdkOptions = getOptions();
@@ -50,7 +50,7 @@ export async function handler(event: ImageHandlerEvent): Promise<ImageHandlerExe
 
     return {
       statusCode: StatusCodes.OK,
-      isBase64Encoded: true,
+      isBase64Encoded: imageRequestInfo.outputFormat === ImageFormatTypes.JSON ? false : true,
       headers,
       body: processedRequest,
     };

source/image-handler/lib/enums.ts

@@ -26,6 +26,7 @@ export enum ImageFormatTypes {
   HEIC = "heic",
   RAW = "raw",
   GIF = "gif",
+  JSON = "json",
 }
 
 export enum ImageFitTypes {

source/image-handler/package.json

@@ -12,7 +12,7 @@
   "scripts": {
     "clean": "rm -rf node_modules/ dist/ coverage/",
     "pretest": "npm run clean && npm ci",
-    "test": "jest --coverage --silent"
+    "test": "jest --watch"
   },
   "dependencies": {
     "aws-sdk": "^2.1477.0",

source/image-handler/test/index.spec.ts

@@ -1,10 +1,13 @@
 // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 // SPDX-License-Identifier: Apache-2.0
 
+import fs from "fs";
+
 import { mockAwsS3 } from "./mock";
 
 import { handler } from "../index";
 import { ImageHandlerError, ImageHandlerEvent, StatusCodes } from "../lib";
+import sharp from "sharp";
 
 describe("index", () => {
   // Arrange
@@ -47,6 +50,59 @@ describe("index", () => {
     expect(result).toEqual(expectedResult);
   });
 
+  it.only("should return a json with metadata when outputFormat='json'", async () => {
+    const originalImage = fs.readFileSync("./test/image/orientation-example.jpg");
+    const image = sharp(originalImage, { failOnError: false }).withMetadata();
+    const buffer = await image.toBuffer();
+
+    // Mock
+    mockAwsS3.getObject.mockImplementationOnce(() => ({
+      promise() {
+        return Promise.resolve({ Body: Buffer.from(buffer), ContentType: "image/jpeg" });
+      },
+    }));
+    // Arrange
+
+    const event: ImageHandlerEvent = {
+      path: btoa(JSON.stringify({ bucket: "source-bucket", key: "test.jpg", outputFormat: "json" })),
+    };
+
+    // Act
+    const result = await handler(event);
+
+    const expectedBody = {
+      format: "jpeg",
+      size: 867153,
+      width: 2316,
+      height: 3088,
+    }
+
+    expect(JSON.parse(result.body)).toEqual(expect.objectContaining(expectedBody));
+
+    const expectedResult = {
+      statusCode: StatusCodes.OK,
+      isBase64Encoded: true,
+      headers: {
+        "Access-Control-Allow-Methods": "GET",
+        "Access-Control-Allow-Headers": "Content-Type, Authorization",
+        "Access-Control-Allow-Credentials": true,
+        "Content-Type": "application/json",
+        Expires: undefined,
+        "Cache-Control": "max-age=31536000,public",
+        "Last-Modified": undefined,
+      },
+    };
+
+    delete result.body;
+
+    // Assert
+    expect(mockAwsS3.getObject).toHaveBeenCalledWith({
+      Bucket: "source-bucket",
+      Key: "test.jpg",
+    });
+    expect(result).toEqual(expectedResult);
+  });
+
   it("should return the image with custom headers when custom headers are provided", async () => {
     // Mock
     mockAwsS3.getObject.mockImplementationOnce(() => ({