Properly Verify

Properly is a simple property object verification tool. You use it to verify that a properties object has all the right properties.

Install

npm install properly-verify

Usage

const properly = require('properly-verify');

var myFunction = function(propertiesToVerify) {
  var properties = properly.check(propertiesToVerify)
    .require('a') // requires the object have a property, a
    .requireNonNull('b') // requires the object have a non-null property b
    .optional('c') // adds the optional property test
    .optional('d', 3) // adds the optional property, d, with a default of 3
    .validate(); // validates the properties and gives you back the object

  // use properties here, knowing you can safely access required members
}

If a property is required but not found, an Error will be thrown.

Validate and Close

In the above example, validate can be replaced with close(). This will give you back your properties object without doing any validation.

Intermediate Validation

If at any point in the validation process you want to stop and do some validation yourself, you can.

After calling properly.check(properties), you get back an object with the form:

{
  'properties': Object, // The original properties object
  'missing': [String], // Any properties missing
  'failed': Boolean // If any of the previous validation steps failed
}

Missing gets entries added to it as they fail to meet requirements. For example:

properly.check({})
  .require('a')
  .optional('b')
  .optional('c', 4);

// properly.missing = ['a', 'b']

Here, a and b are missing because they weren't found. C is not missing, because it's default value of four was used instead.