From b6b8d6814cedd532d3d8909e1df52ae76f31a3ba Mon Sep 17 00:00:00 2001
From: Jochen Schalanda <jochen@schalanda.name>
Date: Mon, 31 Jan 2022 10:48:11 +0100
Subject: [PATCH] Make `requestDriver` more resilient to errors (#46)

If the async request performed in `requestDriver.makeDriver()` fails, it would call the `callback` function with empty parameters but then continue the execution which can lead to the following error and crash of Fredy:
```
Error while trying to scrape data. Received error: Request failed with status code 504
/fredy/lib/services/requestDriver.js:25
    if (typeof result.data === 'object' && url.toLowerCase().indexOf('scrapingant') !== -1) {
                      ^

TypeError: Cannot read properties of undefined (reading 'data')
    at driver (/fredy/lib/services/requestDriver.js:25:23)
    at runMicrotasks (<anonymous>)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
```
---
 lib/services/requestDriver.js | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/lib/services/requestDriver.js b/lib/services/requestDriver.js
index 89ccf44..655f3fd 100644
--- a/lib/services/requestDriver.js
+++ b/lib/services/requestDriver.js
@@ -7,30 +7,29 @@ function makeDriver(headers = {}) {
   let cookies = '';
 
   return async function driver(context, callback) {
-    const url = context.url;
-    let result;
     try {
-      result = await axios({
+      const url = context.url;
+      const result = await axios({
         url,
         headers: {
           ...headers,
           Cookie: cookies,
         },
       });
+
+      if (typeof result.data === 'object' && url.toLowerCase().indexOf('scrapingant') !== -1) {
+        //assume we have gotten a response from scrapingAnt
+        if (cookies.length === 0) {
+          cookies = result.data.cookies;
+        }
+        callback(null, result.data.content);
+      } else {
+        callback(null, result.data);
+      }
     } catch (exception) {
       console.error(`Error while trying to scrape data. Received error: ${exception.message}`);
       callback(null, []);
     }
-
-    if (typeof result.data === 'object' && url.toLowerCase().indexOf('scrapingant') !== -1) {
-      //assume we have gotten a response from scrapingAnt
-      if (cookies.length === 0) {
-        cookies = result.data.cookies;
-      }
-      callback(null, result.data.content);
-    } else {
-      callback(null, result.data);
-    }
   };
 }