(hashlips_art_engine-1.1.2_patch_v5) The "path" argument must be of type string. Received undefined

Question

I'm trying to update some metadata for 10 JSON files, some of them get updated properly and some others give me the following error.

Below you can see 6 files give me errors and 4 files are correctly updated.

---

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

error:TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

5.png uploaded & 5.json updated!

4.png uploaded & 4.json updated!

1.png uploaded & 1.json updated!

7.png uploaded & 7.json updated!

---

This is the node.js code im using:

onst FormData = require('form-data');
const fetch = require('node-fetch');
const path = require("path");
const basePath = process.cwd();
const fs = require("fs");

fs.readdirSync(`${basePath}/build/images`).
forEach(file => {
  const formData = new FormData();
  const fileStream = fs.createReadStream(`${basePath}/build/images/${file}`);
  formData.append("file", fileStream);

  let url = 'https://api.nftport.xyz/v0/files';

  let options = {
    method: 'POST',
    headers: {
      Authorization: 'SecretApiCode',
    },
    body: formData
  };

  fetch(url, options)
    .then(res => res.json())
    .then((json) => {
      const fileName = path.parse(json.file_name).name;
      let rawdata = fs.readFileSync(`${basePath}/build/json/${fileName}.json`);
      let metaData = JSON.parse(rawdata);

      metaData.file_url = json.ipfs_url;

      fs.writeFileSync(`${basePath}/build/json/${fileName}.json`,
        JSON.stringify(metaData, null, 2));

      console.log(`${json.file_name} uploaded & ${fileName}.json updated!`);
      })
    .catch(err => console.error('error:' + err));

});

I have 10png files:

1.png 2.png 3.png 4.png 5.png 6.png 7.png 8.png 9.png 10.png

And 10 JSON files

1.json 2.json 3.json 4.json 5.json 6.json 7.json 8.json 9.json 10.json

Answer 1

The issue in your code seems to be with fetching the URL.

This is proven as sometimes, your code fails with an error, and sometimes, it works successfully.

What might be happening is that sometimes, when you are fetching the data from the URL, it might not have the file_name property (because of an error, etc.)

When you are trying to parse the path with the below method:

path.parse(json.file_name);

The file_name might be undefined as there might not be such a key. And, as path.parse() can't parse undefined, it returns an error, saying that in only accepts strings (shown below).

TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received undefined

---

There are many possible solutions, so they are listed below.

• Add a check for if file_name is available. If it isn't, then don't try parsing it with path.parse(). You can use the code below to check it (in the second .then() method).

  if (!json.file_name) {
    console.error("Error fetching file name.");
    return;
  }
  

• If your API supports it, check if there is an error in the response body. Assuming that the error will be something like .error, you can use the code below for guidance (add it in the second .then() method).

  if (!json.file_name && json.error) {
    console.log(json.error.message);
    return;
  }
  

• There may be many other (better) solutions then these, but these solutions are just to give you a starting point.

_{Solution 1 and 2 are very similar, but they work under different circumstances.}