ilearnio/graphql-type

Create GraphQL types with validation rules

graphql-type

Helper functions for fast creation of graphql types with validation of input or output (or both) values.

In most cases you would want to performs bi-directional validation of data, so that invalid input value will result in an error response, whereas in case of invalid output it will always return the value but will also let you know of the error.

For bi-direction validation use function like createStringType. For uni-directional validation use createStringInputType or createStringOutputType.

Strings

const { createStringType } = require('graphql-type')

const EmailType = createStringType({
  // Name of the type
  name: 'EmailType',
  // Description
  description: 'Email with validation rules.', // (optional)
  // Validation rules
  validate: {
    // Min length
    min: 5,
    // Max length
    max: 100,
    // Regex validation
    regexp: /^\w+@\w+\.[a-z]{2,}$/i,
    // Custom validation function
    test (value) {
      // Disallow emails that end with '@example.com'
      return !value.endsWith('@example.com')
    }
  },
  // Custom error messages
  validationMessages: {
    min: 'Email should have at least 5 characters.',
    test: 'Test domains are not allowed.'
  },
  // Allows to modify or log (or whatnot) the value
  resolve (value) {
    return value
  }
})

Integers

const MyInt = createIntType({
  // Name of the type
  name: 'MyInt',
  // Description
  description: '', // (optional)
  // Validation rules
  validate: {
    // Min number
    min: 5,
    // Max number
    max: 100,
    // Custom validation function
    test: function ...,
  },
  // Custom error messages
  validationMessages: { ... },
  // Allows to modify or log (or whatnot) the value
  resolve (value) {
    return value
  }
})

Floats

const MyFloat = createFloatType({
  // Name of the type
  name: 'MyFloat',
  // Description
  description: '', // (optional)
  validate: {
    // Min number
    min: 5,
    // Max number
    max: 100,
    // Max decimal characters length
    maxDecimals: 4,
    // Custom validation function
    test: function ...,
  },
  // Custom error messages
  validationMessages: { ... },
  // Allows to modify or log (or whatnot) the value
  resolve (value) {
    return value
  }
})

Available helper functions:

// Strings
createStringType(attrs)
createStringInputType(attrs)
createStringOutputType(attrs)

// Integers
createIntType(attrs)
createIntInputType(attrs)
createIntOutputType(attrs)

// Floats
createFloatType(attrs)
createFloatInputType(attrs)
createFloatOutputType(attrs)