api2pdf

api2pdf is an external service to mainly convert HTML and URLs to PDF format. Furthermore it contains other handy features like PDF merging, document conversion, screenshot maker, ...

Sequence diagram

Sensitive data

When authenticated data is shown within the generated PDF, the following approach is used.

As an example, lets say we want to generate a PDF with some user's information. The backend implementation would look something like:

1. Request to generate the PDF

// generate-user-pdf.use-case.ts
const userFile = this.fileRepository.create({
  name: `${userUuid}.pdf`,
  mimeType: MimeType.PDF,
  userUuid: userUuid.uuid,
});

const rsaPrivateKey = this.configService.getOrThrow("RSA_PRIVATE");
const token = this.jwtService.sign(
  { userUuid },
  {
    expiresIn: this.EXPIRES_IN_SECONDS,
    privateKey: rsaPrivateKey,
  }
);

const webUrl = getUserWebUrl(userUuid, token); // https://app.com/users/123?token=xyz
const uploadUrl = await this.s3Service.createTemporaryUploadUrl(userFile);
await this.pdfService.generatePdf(webUrl, uploadUrl);

2. Get user info

// get-user-pdf.guard.ts
const rsaPrivateKey = this.configService.getOrThrow("RSA_PRIVATE");
const tokenContent = this.jwtService.verify(token, { secret: rsaPrivateKey });

const userUuid = request.params["uuid"];
if (verifiedToken.userUuid !== userUuid) {
  throw new UnauthorizedError();
}

// app.module.ts
providers: [
  {
    provide: APP_GUARD,
    useClass: GetUserPdfGuard,
  },
];

// get-user.controller.ts
@GetUserPdfGuard()