validates page capture and cancels upload

if the root html capture doesn't return a status code 200, the upload process is canceled

handler.js

@@ -3,6 +3,8 @@ const s3 = require('s3-node-client');
 const del = require('del');
 const Url = require('url-parse');
 
+const ValidatePlugin = require('./validatePlugin');
+
 const captureURL = new Url(process.env.CAPTURE_URL);
 
 // Allow for a prefix to the subdirectory, and add a slash if it is set.
@@ -20,6 +22,7 @@ const scrapeOptions = {
         {directory: `${subDirPrefix}css`, extensions: ['.css']},
         {directory: `${subDirPrefix}font`, extensions: ['.woff', '.woff2', '.ttf', '.eot']},
     ],
+    plugins: [ new ValidatePlugin() ],
 };
 
 const client = s3.createClient();

validatePlugin.js

@@ -0,0 +1,20 @@
+module.exports = class ValidatePlugin {
+    apply(registerAction) {
+        registerAction('error', async ({error}) => {console.error(error)});
+        registerAction('onResourceError', ({resource, error}) => console.log(`Resource ${resource.url} has error ${error}`));
+        registerAction('afterResponse', async ({response}) => {   
+            if (response.statusCode !== 200) {
+                // Don't capture bad assets.  Also cancels the upload phase if the root page has a bad status code.
+                console.log( `Bad status code ${response.statusCode} , cancelling asset capture` );
+                return null;
+            } else {
+                return {
+                    body: response.body,
+                    metadata: {
+                        headers: response.headers,
+                    }
+                };
+            }
+        });
+    }
+}