Azure Function crasher

function.js

const sshpk = require('sshpk');

function printClientCert(cert) {
    return sshpk.parseCertificate(cert, 'x509');
}

module.exports = function (context, req) {
context.log(
    printClientCert(Buffer.from(req.headers['x-arr-clientcert'], 'base64'))
);
    context.res = {
        status: 200,
        headers: {
            'Content-Type': 'text/json',
        },
        body: {
            cert: printClientCert(Buffer.from(req.headers['x-arr-clientcert'], 'base64')),
        },
    };
    context.done();
};

function.json

{
  "disabled": false,
  "bindings": [
    {
      "authLevel": "anonymous",
      "type": "httpTrigger",
      "direction": "in",
      "route": "cert",
      "name": "req"
    },
    {
      "type": "http",
      "direction": "out",
      "name": "res"
    }
  ]
}

package.json

{
  "name": "test-api",
  "version": "1.0.0",
  "description": "",
  "main": "function.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "UNLICENSED",
  "dependencies": {
    "sshpk": "^1.13.1"
  }
}