如何检查 Json Doc 在 Node JS 中是否具有所有必需的键

Question

I found multiple examples on how to check a json file if a key exist's but i am trying to do this a bit more efficient.

I have an import process where user uploads a csv file and then i convert it to json.

As there is multiple formats in my case for the csv file i want to check if a certain set of fields / keys are present before i import since most of them have different key names.

So to start i go and count the Key count in the json which narrows down my possible definitions. then i would like to use an array of keys which like

["field1", "field2", "field3"] 

and then check if all of them are in my json file. As there a simple way or will it require to loop thru array and check for each key ?

Answer 1

You can pull out the keys from your JSON object, but you still need to loop through the list of "required" keys and check that they exist in the list of keys. Something like the following should do the trick:

const myObject = {}; // getObjectFromCSV();
const required = ["field1", "field2", "field3"];
const objKeys = Object.keys(myObject);
required.every(key => objKeys.includes(key));

To get a list of the missing required fields, I'd do the following. This code would replace the last line above (with the every with the following:

const missingRequired = required.reduce(
  (acc, key) => { 
    if (!objKeys.includes(key)) { 
      acc.push(key);
    } 
    return acc;
  }, []);
const isValid = missingRequired.length === 0;

In the reducer function, acc is the accumulator set to [] initially, if it is empty, then there were no missing keys. Note that the condition is opposite compared to the every function, as we want to know when a key is missing, not if all of them are found.