This document will show how to independently verify the proof of authorship of the publication What is the "Make It Work" stage? authored by Libro Team.

In a zero-knowledge world, the proof of authorship should always be verifiable by external parties. In the longer term, it should be possible for any agent or consumer of content to verify the proof of Human Authorship (HA) and trust the content without relying on Libro or even World's zero-knowledge infrastructure.

As a first step, we provide a way to independently verify the proof of authorship using World's zero-knowledge infrastructure. In the future, we plan to support our own independent implementation of proof verification as well.

Below is a step-by-step guide to verify the proof of authorship of the publication using Node.js. There are two external dependencies:
1. The Worldcoin proof verification implementation and its API endpoint.
2. The Keccak256 hashing algorithm, which is implemented in the ox library.

The script provides the following steps:
1. Gather the data from the document (author, title, subtitle, content, and publication date) in the publication object
2. Gather the data from the proof in the proof object
3. Hash the publication object to create a hash called signal_hash. It is practically impossible to forge a different document with the same hash
4. Create the body of the request
5. Send the request to the Worldcoin API endpoint
6. Print the response, which will be a JSON object. The success field will be true if the proof is valid

Running the script in your trusted environment, like your local machine, should be straightforward. Ensure you have Node.js installed, as well as the ox library (which can be installed with npm install ox).

// 1. Gathering the data from the document (author, title, subtitle, content and publication date) in the publication object
const publication = {
  // ID for this athor, refer to https://worldlibro.com/a/ddcde59d-a70c-48a4-8648-af91da1b5416
  author_id_libro: 'ddcde59d-a70c-48a4-8648-af91da1b5416',
  // This is the name of the author who signed the document
  author_name_libro: "Libro Team",
  // This is the author's handle
  author_handle_libro: "libro",
  // The author's bio is included in the signed payload
  author_bio_libro: "Creator of Libro.",
  // Below are title, subtitle, content and publication date
  publication_title: "What is the \"Make It Work\" stage?",
  publication_subtitle: "",
  publication_content: { html: "<p>The \"Make It Work\" stage is part of a coding philosophy articulated by Kent Beck, which emphasizes a structured approach to software development. This philosophy consists of three main stages: <strong>Make It Work, Make It Right, and Make It Fast</strong>.</p><p></p><strong>Stages of the \"Make It Work\" Philosophy</strong><ol><li><p></p></li><li><p><strong>Make It Work</strong>:</p><ul><li><p>The primary focus is to solve the problem at hand. The goal is to write code that meets the acceptance criteria, ensuring that it functions correctly before any optimizations or refinements are made. This stage prioritizes functionality over perfection, allowing developers to quickly address immediate needs.</p></li></ul></li><li><p></p></li><li><p><strong>Make It Right</strong>:</p><ul><li><p>Once the code works, the next step is to improve its maintainability and readability. This involves refactoring the code to adhere to best practices and coding standards, ensuring that it is clean and easy to understand for future developers.</p></li></ul></li><li><p></p></li><li><p><strong>Make It Fast</strong>:</p><ul><li><p>In this final stage, the emphasis shifts to performance optimization. Developers look for ways to enhance the efficiency of the code without compromising its maintainability. This may involve algorithmic improvements or reducing resource consumption.</p></li></ul></li></ol><p></p><p>This structured approach allows developers to progressively refine their code while ensuring that each version remains functional and maintainable throughout the development process.</p><p></p><p>In addition to this coding philosophy, there are also five stages of team development as proposed by Bruce Tuckman, which include:</p><p><strong>Forming</strong>: Team members get acquainted and establish roles.</p><p><strong>Storming</strong>: Conflicts arise as team members assert their ideas.</p><p><strong>Norming</strong>: The team starts to work collaboratively, building trust.</p><p><strong>Performing</strong>: The team operates at peak efficiency, focusing on achieving goals.</p><p><strong>Adjourning</strong>: The project concludes, and team members reflect on their achievements.</p><p></p><p>Understanding both frameworks can significantly enhance team dynamics and project outcomes in software development and other collaborative environments.</p>" },
  publication_date: '2024-12-09T22:30:08.272Z'
};

// 2. Gather the data from the proof in the proof object
const proof = '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';
const merkle_root = '0x2560e63189afdd79d6698046e839a8c42aecbaa7a952f146b03aae99ef938c5f';
const nullifier_hash = '0x04cc0c13b818eccd1dd9ed97a73311de2696b07e47fe97d0a0d851599c651356';
const verification_level = 'orb';

// 3. Hash the document data to create a signal hash
const input = Buffer.from(JSON.stringify(publication));
const { Hash } = require('ox');
const hash = BigInt(Hash.keccak256(input, { as: 'Hex' })) >> 8n;
const rawDigest = hash.toString(16);
const signal_hash = `0x${rawDigest.padStart(64, '0')}`;

// 4. Create the body of the request
const body = {
  proof,
  merkle_root,
  nullifier_hash,
  verification_level,
  action: 'written-by-a-human',
  signal_hash
};
// 5. Send the request
const app_id = `app_59c12ce689127aa7e62a6a223522755a`;
const url = `https://developer.worldcoin.org/api/v2/verify/${app_id}`;
const response = await fetch(url, {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify(body)
});
// 6. Print the response
const json = await response.json();
console.log(json);