UnhandledPromiseRejectionWarning even though wrapp…

I’m getting the following error message when trying to run storeDirectory().

Why doesn’t my catch() statement not catch the error that is thrown inside addFile()?

My understanding is that errors bubble up to any “outer” catch statement but that doesn’t seem to be the case in my code.

(node:21204) UnhandledPromiseRejectionWarning: Error: HTTP error 500
    at addFile (/Users/joe/dev/node/db/dbFunctions.js:28:11)
    at processTicksAndRejections (internal/process/task_queues.js:95:5)
(Use `node --trace-warnings ...` to show where the warning was created)
(node:21204) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)

//dbFunctions.js
...
const addFile = async (name, type, href) => {
  const response = await fetch("http://localhost:3002/files", {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      name,
      type,
      href
    }),
  });
  if (!response.ok) {
    throw new Error(`HTTP error ${response.status}`);
  }
  return response.json();
};

//app.js
const { addFile } = require("./db/dbFunctions");
...
const storeDirectory = async () => {
  try {
    //create array of files
    const response = await getDirectory();
    const arr = response.directory.items;

    //loop through array and add each item to database
    arr.map((item) => {
      //add item to DB
      addFile(
        item.name,
        item.type,
        item.href
      );
    });
  } catch (error) {
    console.log(error);
  }
};

Answer

try will only catch asynchronous errors if the Promise is awaited. Change

arr.map((item) => {
  //add item to DB
  addFile(
    item.name,
    item.type,
    item.href
  );
});

await Promise.all(arr.map((item) => 
  //add item to DB
  addFile(
    item.name,
    item.type,
    item.href
  );
));

making sure to return the Promise from the .map.

UnhandledPromiseRejectionWarning even though wrapped in try/catch()

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Answer