Integrate using AWS CloudFront with Lambda@Edge

import { GetObjectCommand, S3Client } from '@aws-sdk/client-s3';
const client = new S3Client();

function getObject(Bucket, Key) {
  return new Promise(async (resolve, reject) => {
    const getObjectCommand = new GetObjectCommand({ Bucket, Key })

    try {
      const response = await client.send(getObjectCommand)
      let responseDataChunks = [];

      response.Body.once('error', err => reject(err));
      response.Body.on('data', chunk => responseDataChunks.push(chunk));

      // Once the stream has no more data, join the chunks into a string and return the string
      response.Body.once('end', () => resolve(responseDataChunks.join('')));
    } catch (err) {
      // Handle the error or throw
      return reject(err);
    }
  })
}

export const handler = async (event) => {
    const response = event.Records[0].cf.response;
    const request = event.Records[0].cf.request;
    const headers = response.headers;
    const contentType = response.headers['content-type'][0].value;
    let path = request.uri;

    if (contentType && contentType?.startsWith("text/html")) {
        if (path == '/') {
          path = "index.html";
        }
        const object = await getObject('<S3_BUCKET_NAME>', path); // fetching the proper html file from the S3 bucket according to the request uri

        const tsPlatformSDK = `
          <script src="https://platform-websdk.transmitsecurity.io/platform-websdk/1.x/ts-platform-websdk.js" defer="true" id="ts-platform-script"></script>
          <script>
             console.log("Setting up event listener for script loading");
             // Initialize the Platform SDK
             // See changelog for details and update version if necessary
             document.getElementById("ts-platform-script").addEventListener("load", function() {
                 window.tsPlatform.initialize({
                    clientId: "[CLIENT_ID]", // Obtained in Step 1
                    drs: { userId: "[USER_ID]" } // If user ID is known
                 });
             });

            // Trigger the specific actions per page:
            const url = window.location.href;

            document.addEventListener('DOMContentLoaded' , async function() {
              if (url.includes("/login")) { // Example: your login page URL
                // Add code here to delay script execution until the relevant DOM elements are rendered

                // Trigger events for the login button and get the actionToken
                document.getElementById("login_button").addEventListener('click', async function(e) {
                  await window.tsPlatform.drs.triggerActionEvent("login", { correlationId: "[CORRELATION_ID]" }).then((actionResponse) => {
                    let actionToken = actionResponse.actionToken;
                   // Add code here to send the received actionToken to your backend

                  });
                });

                // Set the user for all subsequent events in the browser session
                const userId = window.localStorage.getItem("userID"); // Get a user identifier, for example from the local storage
                if (userId) {
                  await window.tsPlatform.drs.setAuthenticatedUser('userId');
                }
              } else {
                  // When on a page with a logout button
                  // Clear the set user after the user logs out or the user session expires

                  async function onUserLogout() {
                    await window.tsPlatform.drs.clearUser();
                  }
                  let logoutButton = document.getElementById("logout");
                  if (logoutButton) {
                    logoutButton.addEventListener('click', onUserLogout);
                  }
              }
            });
          </script>
        `;

        // Consider appending the script to </body> instead of </head> if it's relevant for your use case
        const modifiedBody = object.replace('</head>', tsPlatformSDK + '</head>');
        if (modifiedBody) {
            response.body = modifiedBody;
        }
    }
    return response;
};

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "ListObjectsInBucket",
      "Effect": "Allow",
      "Action": [
                "s3:Get*",
                "s3:List*",
                "s3:Describe*",
                "s3-object-lambda:Get*",
                "s3-object-lambda:List*"
      ],
      "Resource": [
        "arn:aws:s3:::<S3_BUCKET_NAME>" // Replace with your S3 bucket name
      ]
    },
    {
      "Sid": "AllObjectActions",
      "Effect": "Allow",
      "Action": "s3:*Object*",
      "Resource": [
        "arn:aws:s3:::<S3_BUCKET_NAME>/*" // Replace with your S3 bucket name
      ]
    }
  ]
}

  const { access_token } = await fetch(
    `https://api.transmitsecurity.io/oidc/token`,
    {
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded'
      }
      body: new URLSearchParams({
        grant_type: client_credentials,
        client_id: [CLIENT_ID], // Obtained in Step 1
        client_secret: [CLIENT_SECRET], // Obtained in Step 1
        resource: 'https://risk.identity.security'
      })
    }
  );

const query = new URLSearchParams({
  action_token: '[ACTION_TOKEN]', // Returned by SDK
}).toString();

const resp = await fetch(
  `https://api.transmitsecurity.io/risk/v1/recommendation?${query}`,
  {
    method: 'GET',
    headers: {
      Authorization: 'Bearer [ACCESS_TOKEN]', // Obtained using Client ID and Secret
    },
  }
);