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How to log an object in Node

Logging objects in Node.js

When you type console.log() into a JavaScript program that runs in the browser, that is going to create a nice entry in the Browser Console:

Once you click the arrow, the log is expanded, and you can clearly see the object properties:

In Node, the same happens.

We donโ€™t have such luxury when we log something to the console, because thatโ€™s going to output the object to the shell if you run the Node program manually, or to the log file. You get a string representation of the object.

Now, all is fine until a certain level of nesting. After two levels of nesting, Node gives up and prints [Object] as a placeholder:

const obj = {
  name: 'Flavio',
  age: 35,
  person1: {
    name: 'Tony',
    age: 50,
    person2: {
      name: 'Albert',
      age: 21,
      person3: {
        name: 'Peter',
        age: 23
      }
    }
  }
}
console.log(obj)


{
  name: 'Flavio',
  age: 35,
  person1: {
    name: 'Tony',
    age: 50,
    person2: {
      name: 'Albert',
      age: 21,
      person3: [Object]
    }
  }
}

How can you print the whole object?

The best way to do so, while preserving the pretty print, is to use

console.log(JSON.stringify(obj, null, 2))

where 2 is the number of spaces to use for indentation.

Another option is to use

require('util').inspect.defaultOptions.depth = null
console.log(obj)

but the problem is that the nested objects after level 2 are now flattened, and this might be a problem with complex objects.

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