Liftoff, Hello Space!

To get started, let's walk through a binding process with the most frequently used platform: Twitter. Hold tight, let's go!

Prerequisites

Basics in Cryptography
Basics in Python, TypeScript and Node.js
Basics in Postman or cURL
Or any programming languages and required libraries you prefer
Knowing nothing but keen on learning? Don't panic, it's okay! You can learn it all in just a few hours!

Set up your first Avatar

In the Crypto world, a cryptographic key pair is what stands as one of your AVATARs. Next.ID uses by far the most secure algorithm to protect your sovereignty: curve secp256k1.

We're showing it by using Python's secp256k1-py.

First to install secp256k1-py lib:

// get PIP installed in advance or use your own way
pip install secp256k1

Then generate your own private and public key pair:

python -m secp256k1 privkey -p

// ATTENTION! We intently replaced the last three digit of private key to be xxx.
// Private key is everything and NEVER expose it to others or publicly
43c25fecc20e6b2a0d86c81a0202d125c0181deb9975d1170d80378c7e05bxxx
Public key: 03bce884894fdc4fb45475733be317dd3c289f003bceebb097ac79a6b95e6edc56

Having this one key pair, you now can get to create an Avatar backed by unbreakable cryptography.

Binding Twitter account

From now on, we're demonstrating the whole process by using a Twitter Handle and key-pair generated as above. Replace all fields to be your own as you go on, you'll get acknowledged when and where you should do it.

Especially your_twitter_handle is where you'll be replacing it with your own.

Get a payload

If We're heading into space, there'll be a Rocket carrying us as a payload. Joining Cyberspace each time is quite similar.

First, let's get the payload needed to represent us. Calling REST API /proof/payload by using POSTMAN or using cURL in the command line:

Replace the fields of identity and public_key to be your own, then it will return like:

{
    "post_content": {
        "default": "🎭 Verifying my Twitter ID @your_twitter_handle for @NextDotID.\nSig: %SIG_BASE64%\n\nInstall Mask.io to enhance your Web3 experience.\n",
        "en_US": "🎭 Verifying my Twitter ID @your_twitter_handle for @NextDotID.\nSig: %SIG_BASE64%\n\nInstall Mask.io to enhance your Web3 experience.\n",
        "zh_CN": "🎭 正在通过 @NextDotID 验证我的 Twitter 帐号 @your_twitter_handle 。\nSig: %SIG_BASE64%\n\n请下载安装 Mask.io 去增强您的 Web3 体验。\n"
    },
    "sign_payload": "{\"action\":\"create\",\"created_at\":\"1656843378\",\"identity\":\"your_twitter_handle\",\"platform\":\"twitter\",\"prev\":\"KNyNFtvhlRVJh/oU6RryK2n+C2dja9aLQPjlv5VHMsQErZROojEmMAgmeEQVC094EOuHIYcv3lCYXf8d3zqDCQE=\",\"uuid\":\"77f5ccaa-7919-4854-96de-81975f96744a\"}",
    "uuid": "77f5ccaa-7919-4854-96de-81975f96744a",
    "created_at": "1656843378"
}

sign_payload is the payload we're looking for. uuid and created_at are also required for the following steps.

Generate the signature

With the payload returned, now we can go ahead to sign it. Git clones our open-source Demo in TypeScript to accomplish it.

Notice that, you need to set up Node.js and TypeScript before downloading, then go to install the required libs as ethereumjs-util.

Let's open up the index.ts file under /src, and replace the const message with the string sign_payload in the former step:

import { ecsign, toRpcSig, keccakFromString, BN } from 'ethereumjs-util';

async function personalSign(message: Buffer, privateKey: Buffer): Promise<Buffer> {
    const messageHash = keccakFromString(`\x19Ethereum Signed Message:\n${message.length}${message}`, 256)
    const signature = ecsign(messageHash, privateKey)
    return Buffer.from(toRpcSig(signature.v, signature.r, signature.s).slice(2), 'hex')
}

async function main() {
    // this message come from the return attribute "sign_payload" of everytime calling API: v1/proof/payload
    const message = Buffer.from('{\"action\":\"create\",\"created_at\":\"1656843378\",\"identity\":\"your_twitter_handle\",\"platform\":\"twitter\",\"prev\":\"KNyNFtvhlRVJh/oU6RryK2n+C2dja9aLQPjlv5VHMsQErZROojEmMAgmeEQVC094EOuHIYcv3lCYXf8d3zqDCQE=\",\"uuid\":\"353449e6-3a6f-4ac8-ae65-ba14bf466baf\"}', 'utf8');
    // ATTENTION! RUN THIS LOCALLY! NEVER SHARE YOUR PRIVATE KEY WITH ANY OTHERS OR PUBLIC!
    // replace XXX with your own Private Key for generating a signature
    const secretKey = Buffer.from('XXX', 'hex');
    const signature = await personalSign(message, secretKey);

    console.log(`Signature: 0x${signature.toString('hex')}`);
    // For demo ONLY
    // Signature: 0xf72fe6b00be411bd70ffe1b9bf322f18529ea10e9559dd26ba10387544849fc86d712709dfb709efc3dcc0a01b6f6b9ca98bd48fe780d58921f4926c6f2c0b871b

    console.log(`Signature(base64): ${signature.toString('base64')}`);
    // For demo ONLY
    // Signature(base64): 9y/msAvkEb1w/+G5vzIvGFKeoQ6VWd0muhA4dUSEn8htcScJ37cJ78PcwKAbb2ucqYvUj+eA1Ykh9JJsbywLhxs=
}

main();

Now we can run it properly. Go to the root directory to compile:

➜  Generating-Signature-TypeScript git:(main) tsc

Go to the /disc directory to get it running:

➜  dist git:(main) ✗ node index.js

We will get two console.log outputs. One is the Signature(base64) that we're going to use for proof posting on Twitter.

Post a proof Tweet

Follow the format we get in calling /proof/payload, replace the Sig with Signature(base64) we just get and visit twitter.com to tweet as below:

🎭 Verifying my Twitter ID @your_twitter_handle for @NextDotID.
Sig: 9y/msAvkEb1w/+G5vzIvGFKeoQ6VWd0muhA4dUSEn8htcScJ37cJ78PcwKAbb2ucqYvUj+eA1Ykh9JJsbywLhxs=

Next.ID YOUR DIGITAL IDENTITIES IN ONE PLACE

Then go to the detail page of this tweet, get its ID at the end of the URL like `1543541274254639104``:

https://twitter.com/your_twitter_handle/status/1543541274254639104

This ID will be the proof_location we needed for verifying.

Verify the proof

We're getting close! Calling REST API /proof by using POSTMAN or using cURL in the command line:

It will return a code of 201 Created` and empty curly brackets :

{}

Check the status of Avatar

All set! Let's go to have a look at our newly created Avatar.

Calling REST API /proof in GET method and with two fields of platform and identity:

https://proof-service.next.id/v1/proof?platform=twitter&identity=your_twitter_handle

We will get as below:

{
    "pagination": {
        "total": 4,
        "per": 20,
        "current": 1,
        "next": 0
    },
    "ids": [
        {
            "avatar": "0x03bce884894fdc4fb45475733be317dd3c289f003bceebb097ac79a6b95e6edc56",
            "proofs": [
                {
                    "platform": "twitter",
                    "identity": "your_twitter_handle",
                    "created_at": "1656844114",
                    "last_checked_at": "1656844114",
                    "is_valid": true,
                    "invalid_reason": ""
                }
            ]
        }
    ]
}

Now you successfully created an Avatar on-chain as who you're. Go exploring cyberspace ahead!

Next Step

View the [architecture] of Next.ID framework(../core-concepts/architecture.md)
Understand how it works in detail

Prerequisites​

Set up your first Avatar​

Binding Twitter account​

Get a payload​

Generate the signature​

Post a proof Tweet​

Verify the proof​

Check the status of Avatar​

Next Step​