HTTP 重新導向管理

function handler(event) {
  var request = event.request;
  var headers = request.headers;
  var host = request.headers.host.value;
  var supported_countries = ['ie','ae', 'es']; // countries in which you'd like to serve a localized version of your Single Page Application
  var defaultCountryIndex = 0; // default country index in the support_countries array. here it is 'ie'
  
  if ((supported_countries.includes(request.uri.substring(1,3))) && ((request.uri.substring(3,4) === '/') || (request.uri.length === 3))) {
      // If one of the supported country codes is included in the path (e.g. /es/about) then add index.html when needed to the reauest
      return requestWithIndexHTML(request);
  } else if ((headers['cloudfront-viewer-country']) && (headers['cloudfront-viewer-country'].value.toLowerCase() !== supported_countries[defaultCountryIndex])){
      // Otherwise if the user reauest is coming from one of the supported countries except the default one, then redirect to country specific version (e.g. /about -> /es/about)
      var response = {
          statusCode: 302,
          statusDescription: 'Found',
          headers: { location: { value: `https://${host}/${headers['cloudfront-viewer-country'].value.toLowerCase()}${request.uri}` } },
      };
      return response;      
  } else {
      // Otherwise send rewrite the request to the default country path, add index.html if needed and return
      request.uri = '/'+supported_countries[defaultCountryIndex] + request.uri;
      return requestWithIndexHTML(request);
  }
}

// Add index.html to SPA path when needed
function requestWithIndexHTML(request) {
    if (request.uri.endsWith('/')) {
        request.uri += 'index.html';
    } else if (!request.uri.includes('.')) {
        request.uri += '/index.html';
    }
    return request;
}