tests: add unit tests for the downloadImageFromURLAsBase64() function

Author: pacyL2K19

src/utils/base64.test.ts

@@ -0,0 +1,64 @@
+import { httpClient } from '../connection/http.js';
+import { downloadImageFromURLAsBase64 } from './base64.js';
+
+jest.mock('../connection/http.js');
+
+describe('downloadImageFromURLAsBase64()', () => {
+  const mockHttpClient = {
+    externalGet: jest.fn(),
+  };
+
+  beforeEach(() => {
+    jest.clearAllMocks();
+    (httpClient as jest.Mock).mockReturnValue(mockHttpClient);
+  });
+
+  it('should convert a downloaded image to base64', async () => {
+    const mockUrl = 'https://example.com/image.jpg';
+    const mockImageData = Buffer.from('image binary data');
+
+    mockHttpClient.externalGet.mockResolvedValue(mockImageData);
+
+    const result = await downloadImageFromURLAsBase64(mockUrl);
+
+    expect(result).toBe(mockImageData.toString('base64'));
+    expect(httpClient).toHaveBeenCalledWith({ headers: { 'Content-Type': 'image/*' }, host: '' });
+    expect(mockHttpClient.externalGet).toHaveBeenCalledWith(mockUrl);
+  });
+
+  it('should throw an error if the URL is invalid', async () => {
+    const invalidUrl = 'invalid-url';
+
+    await expect(downloadImageFromURLAsBase64(invalidUrl)).rejects.toThrow('Invalid URL');
+  });
+
+  it('should throw an error if the image download fails', async () => {
+    const mockUrl = 'https://example.com/image.jpg';
+
+    mockHttpClient.externalGet.mockRejectedValue(new Error('Network error'));
+
+    await expect(downloadImageFromURLAsBase64(mockUrl)).rejects.toThrow('Failed to download image from URL');
+    expect(httpClient).toHaveBeenCalledWith({ headers: { 'Content-Type': 'image/*' }, host: '' });
+    expect(mockHttpClient.externalGet).toHaveBeenCalledWith(mockUrl);
+  });
+
+  it('should handle empty response data gracefully', async () => {
+    const mockUrl = 'https://example.com/image.jpg';
+
+    mockHttpClient.externalGet.mockResolvedValue(Buffer.alloc(0));
+
+    const result = await downloadImageFromURLAsBase64(mockUrl);
+
+    expect(result).toBe('');
+    expect(httpClient).toHaveBeenCalledWith({ headers: { 'Content-Type': 'image/*' }, host: '' });
+    expect(mockHttpClient.externalGet).toHaveBeenCalledWith(mockUrl);
+  });
+
+  it('should throw an error if the response is not a buffer', async () => {
+    const mockUrl = 'wrong-url.com';
+
+    mockHttpClient.externalGet.mockResolvedValue('not a buffer');
+
+    await expect(downloadImageFromURLAsBase64(mockUrl)).rejects.toThrow('Invalid URL');
+  });
+});

src/utils/base64.ts

@@ -33,14 +33,24 @@ const isUrl = (file: string | Buffer): boolean => {
   }
 };
 
-const downloadImageAsBase64 = async (url: string): Promise<string> => {
+export const downloadImageFromURLAsBase64 = async (url: string): Promise<string> => {
+  if (!isUrl(url)) {
+    throw new Error('Invalid URL');
+  }
+
   try {
     const client = httpClient({
       headers: { 'Content-Type': 'image/*' },
       host: '',
     });
+
     const response = await client.externalGet(url);
-    return Buffer.from(response, 'binary').toString('base64');
+
+    if (!Buffer.isBuffer(response)) {
+      throw new Error('Response is not a buffer');
+    }
+
+    return response.toString('base64');
   } catch (error) {
     throw new Error(`Failed to download image from URL: ${url}`);
   }
@@ -62,7 +72,7 @@ const fileToBase64 = (file: string | Buffer): Promise<string> =>
       : isBuffer(file)
       ? Promise.resolve(file.toString('base64'))
       : isUrl(file)
-      ? downloadImageAsBase64(file)
+      ? downloadImageFromURLAsBase64(file)
       : Promise.resolve(file)
   );