mutent-json-schema

This plugin for Mutent will inject a set of Hooks that will validate that all Entities match with the desired JSON Schema.

The validation will be performed when any Entity is loaded (onEntity hook) and before any Adapter's write op (beforeCreate and beforeUpdate hooks).

Install

npm i mutent-json-schema

API

mutentJsonSchema(options)

Returns a new Mutent's Plugin that enforces a JSON Schema to all Entities.

• options <Object>
• [options.ajv] <Ajv> A customized instance of Ajv. Optional.
• [options.ajvOptions] <Object> Custom options for the Ajv constructor function. Optional defaults are documented below.
• options.schema <*> The required JSON Schema to enforce. Schemas generated with fluent-json-schema are also supported.
• Returns: <Plugin>

Default Ajv options

Those are the default options used to create the internal Ajv instance.

new Ajv({
  allErrors: process.env.NODE_ENV !== 'production',
  coerceTypes: true,
  removeAdditional: true,
  useDefaults: true,
  ...pluginOptions.ajvOptions
})

JSON Schema errors

When an Entity with an invalid schema is detected, an error will be thrown. The error is an instance of MutentError with the "EMUT_INVALID_ENTITY" code.

You can access the raw Ajv-generated errors, and the Entity that has generated those errors, from the .info.errors and .info.data properties respectively.

Example

import { Store } from 'mutent'
import { ArrayAdapter } from 'mutent-array'
import { mutentJsonSchema } from 'mutent-json-schema'

const store = new Store({
  adapter: new ArrayAdapter(),
  plugins: [
    mutentJsonSchema({
      schema: {
        type: 'object',
        additionalProperties: false,
        properties: {
          id: {
            type: 'string'
          },
          value: {
            type: 'integer'
          }
        },
        required: ['id', 'value']
      }
    })
  ]
})

async function foo () {
  try {
    await store.create({}).unwrap()
  } catch (err) {
    console.error(err)
    // err.code will be 'EMUT_INVALID_ENTITY'
    // err.info.data will contain the data that triggered the error
    // err.info.errors will contain Ajv errors
  }
  
  await store.create({ id: 'my_entity', value: 42 }).unwrap()

  console.log(store.adapter.items) // [ { id: 'my_entity', value: 42 } ]
}

foo()

License

Licensed under MIT.