PoW API

This is a simple API that allows you to generate a proof of work challenges and verify the proof of work.

The API has two endpoints:

• GET /pow/challenge - This endpoint generates a new proof of work challenge.
• POST /pow/challenge - This endpoint verifies a proof of work challenge.

The proof of work challenge is to find a proof which, when concatenated and hashed (via SHA 512) with a challenge string that starts with a certain number of zeros. The number of zeros is determined by the difficulty level. The difficulty level is a number between 1 and 10. The higher the difficulty level, the more zeros the string must start with.

The current difficulty is {{difficulty}}.

The example code for performing a proof of work challenge is:

          const crypto = require('crypto');
          const axios = require('axios');

          async function getChallenge() {
            const response = await axios.get('https://api.us.dev/pow/challenge');
            return response.data;
          }

          async function submitSolution(challenge, proof) {
            const response = await axios.post('https://api.us.dev/pow/challenge', {
              challenge,
              proof
            });
            return response.data;
          }

          function hashProof(challenge, proof) {
            return crypto.createHash('sha512').update(challenge + proof).digest('hex');
          }

          function verifyChallenge(hash: string, difficulty: number) {
            return hash.startsWith('0'.repeat(difficulty));
          } 

          async function proofOfWork() {
            const challenge = await getChallenge();
            let proof = 0;
            let hash = '';
            do {
              proof++;
              hash = hashProof(challenge, proof);
            } while (!verifyChallenge(hash, 5));
            return await submitSolution(challenge, proof);
          }

          proofOfWork().then(console.log).catch(console.error);
          

If you're a developer you should use the GET /pow/challenge endpoint to get the challenge, then pass the challenge to your client, then have the client find a solution to the challenge and then submit their proof as part of their later action. Your service should then verify the solution using the POST /pow/challenge endpoint (or your own local implementation) to verify the solution.