request with hmac example

request_with_hmac_example.js

/***********************************************************************************************************************
 * MAKE REQUEST WITH HMAC TO API
 **********************************************************************************************************************/
const fs             = require('fs');
const http           = require('https');
const Hmmac          = require('hmmac');

const USER           = process.env.HMAC_USER            || '<username>';
const SECRET         = process.env.HMAC_SECRET          || '<secret>';
const SIGNED_HEADERS = process.env.HMAC_SIGNED_HEADERS  || 'accept,date,host';
const HOST           = process.env.HMAC_HOST            || '<host>';
const PORT           = process.env.HMAC_PORT            || '443';
const UPLOAD_FILE    = process.env.HMAC_UPLOAD_FILE     || null;
const METHOD         = process.env.HMAC_METHOD          || (UPLOAD_FILE ? 'POST' : 'GET');
const PATH           = process.env.HMAC_PATH            || (UPLOAD_FILE ? '/data/engagement_stats' : '/data/candidates');

const httpRequest    = {
    host      : HOST,
    port      : PORT,
    path      : PATH,
    method    : METHOD,
    body      : '',
    headers   : {
        'X-Auth-SignedHeaders'  : SIGNED_HEADERS,
        'Accept'                : '*/*',
        'Date'                  : new Date().toUTCString()
    }
};

if (UPLOAD_FILE) {
    const data          = fs.readFileSync(UPLOAD_FILE);

    const boundary      = `--${Math.random().toString(16).replace('.', '')}`;
    const delimiter     = `\r\n--${boundary}`;
    const multipartBody = Buffer.concat([
        Buffer.from(`${delimiter}\r\nContent-Disposition: form-data; name="file"; filename="file.csv"\r\n\r\n`),
        data,
        Buffer.from(`${delimiter}--`)]
    );

    httpRequest.headers['Content-Type']   = 'multipart/form-data; boundary=' + boundary;
    httpRequest.headers['Content-Length'] = multipartBody.length;

    httpRequest.rbody = multipartBody;
}


const hmmac         = new Hmmac({
    scheme          : Hmmac.schemes.load('plain'),
    signedHeaders   : SIGNED_HEADERS.split(','),
});


hmmac.sign(httpRequest, { key : USER, secret : SECRET });

httpRequest.body    = httpRequest.rbody || '';

const req           = http.request(httpRequest, res => {
    console.log('\tdone.');
    console.log('\thandling response ...\n\n');

    let body = '';

    res.on('data', chunk => body += chunk);
    res.on('end',  ()    => { console.log('\n\n\tHTTP %s Response: %s', res.statusCode, body); process.exit(); });
});

console.log('\n\n\tmaking request ...');

req.write(httpRequest.body);
req.end();