# schema-required-properties-defined

Source: https://apigenie.pl/docs/linter/openapi/rules/schema-required-properties-defined

This rule checks that every name listed in `required` is defined in `properties`.

## Rule Details

A required property which is not defined is usually a typo (`required: [nmae]`) or a
property removed from `properties` but not from `required`. Its value is not described,
and generated code often cannot represent it.

The rule looks for the definition wherever the schema's value is also described:

- in the schema's `allOf` members, following references;
- in the schemas using it in `allOf`, `anyOf`, `oneOf`, `not`, `if`, `then` or `else`,
  and in their other members. This accepts common patterns such as
  `anyOf: [{required: [email]}, {required: [phone]}]` below a schema defining both
  properties, or a mixin requiring a property that the schemas using it define.

Schemas which allow undeclared properties on purpose are skipped: those with
`patternProperties`, a schema in `additionalProperties`, or `additionalProperties: true`.
Schemas whose references cannot be resolved are skipped too.

`required` in a schema which does not allow objects, for example beside `items` in an
array schema instead of inside it, has no effect and is reported as such.

## Configuration

None.

## Examples

**Good**.

```yaml
components:
  schemas:
    User:
      type: object
      required: [id, name]
      properties:
        id:
          type: string
        name:
          type: string
```

**Bad**. `nmae` is not defined.

```yaml
components:
  schemas:
    User:
      type: object
      required: [id, nmae]
      properties:
        id:
          type: string
        name:
          type: string
```

**Bad**. `required` applies to the array, not to its items.

```yaml
components:
  schemas:
    Packages:
      type: array
      items:
        type: object
        properties:
          name:
            type: string
      required: [name]
```

## When Not to Use It

Disable this rule when required properties are intentionally left undescribed.

## Compatibility

This rule is compatible with all OpenAPI 3.x versions.