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6-async/04-promise-api/02-promise-errors-as-results-2/task.md

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+# Fault-tolerant fetch with JSON
+
+Improve the solution of the previous task <info:task/promise-errors-as-results>. Now we need not just to call `fetch`, but to load the JSON objects from given URLs.
+
+Here's the example code to do that:
+
+```js run
+let urls = [
+  'https://api.github.com/users/iliakan',
+  'https://api.github.com/users/remy',
+  'https://api.github.com/users/jeresig'
+];
+
+// make fetch requests
+Promise.all(urls.map(url => fetch(url)))
+  // map each response to response.json()
+  .then(responses => Promise.all(
+    responses.map(r => r.json())
+  ))
+  // show name of each user
+  .then(users => {  // (*)
+    for(let user of users) {
+      alert(user.name);
+    }
+  });
+```
+
+The problem is that if any of requests fails, then `Promise.all` rejects with the error, and we loose results of all the other requests. So the code above is not fault-tolerant, just like the one in the previous task.
+
+Modify the code so that the array in the line `(*)` would include parsed JSON for successful requests and error for errored ones.
+
+Please note that the error may occur both in `fetch` (if the network request fails) and in `response.json()` (if the response is invalid JSON). In both cases the error should become a member of the results object.
+
+The sandbox has both of these cases.