Extend @kbn/config-schema

packages/kbn-config-schema/src/index.ts

@@ -36,6 +36,8 @@ import {
   MapOfOptions,
   MapOfType,
   MaybeType,
+  NeverOptions,
+  NeverType,
   NumberOptions,
   NumberType,
   ObjectType,
@@ -72,7 +74,7 @@ function uri(options?: URIOptions): Type<string> {
   return new URIType(options);
 }
 
-function literal<T extends string | number | boolean>(value: T): Type<T> {
+function literal<T extends string | number | boolean | null>(value: T): Type<T> {
   return new LiteralType(value);
 }
 
@@ -88,6 +90,10 @@ function duration(options?: DurationOptions): Type<Duration> {
   return new DurationType(options);
 }
 
+function never(options?: NeverOptions): Type<never> {
+  return new NeverType(options);
+}
+
 /**
  * Create an optional type
  */
@@ -167,7 +173,7 @@ function siblingRef<T>(key: string): SiblingReference<T> {
 
 function conditional<A extends ConditionalTypeValue, B, C>(
   leftOperand: Reference<A>,
-  rightOperand: Reference<A> | A,
+  rightOperand: Reference<A> | A | Type<unknown>,
   equalType: Type<B>,
   notEqualType: Type<C>,
   options?: TypeOptions<B | C>
@@ -186,6 +192,7 @@ export const schema = {
   literal,
   mapOf,
   maybe,
+  never,
   number,
   object,
   oneOf,

packages/kbn-config-schema/src/references/reference.ts

@@ -22,7 +22,7 @@ import { internals, Reference as InternalReference } from '../internals';
 export class Reference<T> {
   public static isReference<V>(value: V | Reference<V> | undefined): value is Reference<V> {
     return (
-      value !== undefined &&
+      value != null &&
       typeof (value as Reference<V>).getSchema === 'function' &&
       internals.isRef((value as Reference<V>).getSchema())
     );

packages/kbn-config-schema/src/types/conditional_type.test.ts

@@ -114,6 +114,72 @@ test('properly validates types according chosen schema', () => {
   ).toEqual('a');
 });
 
+test('properly validates when compares with Schema', () => {
+  const type = schema.conditional(
+    schema.contextRef('context_value_1'),
+    schema.number(),
+    schema.string({ minLength: 2 }),
+    schema.string({ minLength: 3 })
+  );
+
+  expect(() =>
+    type.validate('a', {
+      context_value_1: 0,
+    })
+  ).toThrowErrorMatchingSnapshot();
+
+  expect(
+    type.validate('ab', {
+      context_value_1: 0,
+    })
+  ).toEqual('ab');
+
+  expect(() =>
+    type.validate('ab', {
+      context_value_1: 'b',
+    })
+  ).toThrowErrorMatchingSnapshot();
+
+  expect(
+    type.validate('abc', {
+      context_value_1: 'b',
+    })
+  ).toEqual('abc');
+});
+
+test('properly validates when compares with "null" literal Schema', () => {
+  const type = schema.conditional(
+    schema.contextRef('context_value_1'),
+    schema.literal(null),
+    schema.string({ minLength: 2 }),
+    schema.string({ minLength: 3 })
+  );
+
+  expect(() =>
+    type.validate('a', {
+      context_value_1: null,
+    })
+  ).toThrowErrorMatchingSnapshot();
+
+  expect(
+    type.validate('ab', {
+      context_value_1: null,
+    })
+  ).toEqual('ab');
+
+  expect(() =>
+    type.validate('ab', {
+      context_value_1: 'b',
+    })
+  ).toThrowErrorMatchingSnapshot();
+
+  expect(
+    type.validate('abc', {
+      context_value_1: 'b',
+    })
+  ).toEqual('abc');
+});
+
 test('properly handles schemas with incompatible types', () => {
   const type = schema.conditional(
     schema.contextRef('context_value_1'),

packages/kbn-config-schema/src/types/conditional_type.ts

@@ -27,15 +27,18 @@ export type ConditionalTypeValue = string | number | boolean | object | null;
 export class ConditionalType<A extends ConditionalTypeValue, B, C> extends Type<B | C> {
   constructor(
     leftOperand: Reference<A>,
-    rightOperand: Reference<A> | A,
+    rightOperand: Reference<A> | A | Type<unknown>,
     equalType: Type<B>,
     notEqualType: Type<C>,
     options?: TypeOptions<B | C>
   ) {
     const schema = internals.when(leftOperand.getSchema(), {
-      is: Reference.isReference(rightOperand) ? rightOperand.getSchema() : rightOperand,
-      otherwise: notEqualType.getSchema(),
+      is:
+        Reference.isReference(rightOperand) || rightOperand instanceof Type
+          ? rightOperand.getSchema()
+          : rightOperand,
       then: equalType.getSchema(),
+      otherwise: notEqualType.getSchema(),
     });
 
     super(schema, options);

packages/kbn-config-schema/src/types/index.ts

@@ -33,3 +33,4 @@ export { RecordOfOptions, RecordOfType } from './record_type';
 export { StringOptions, StringType } from './string_type';
 export { UnionType } from './union_type';
 export { URIOptions, URIType } from './uri_type';
+export { NeverOptions, NeverType } from './never_type';

packages/kbn-config-schema/src/types/literal_type.test.ts

@@ -33,6 +33,10 @@ test('handles number', () => {
   expect(literal(123).validate(123)).toBe(123);
 });
 
+test('handles null', () => {
+  expect(literal(null).validate(null)).toBe(null);
+});
+
 test('returns error when not correct', () => {
   expect(() => literal('test').validate('foo')).toThrowErrorMatchingSnapshot();
 
@@ -41,6 +45,8 @@ test('returns error when not correct', () => {
   expect(() => literal('test').validate([1, 2, 3])).toThrowErrorMatchingSnapshot();
 
   expect(() => literal(123).validate('abc')).toThrowErrorMatchingSnapshot();
+
+  expect(() => literal(null).validate(42)).toThrowErrorMatchingSnapshot();
 });
 
 test('includes namespace in failure', () => {

packages/kbn-config-schema/src/types/never_type.test.ts

@@ -0,0 +1,81 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { schema } from '..';
+
+test('throws on any value set', () => {
+  const type = schema.never();
+
+  expect(() => type.validate(1)).toThrowErrorMatchingSnapshot();
+  expect(() => type.validate('a')).toThrowErrorMatchingSnapshot();
+  expect(() => type.validate(null)).toThrowErrorMatchingSnapshot();
+  expect(() => type.validate({})).toThrowErrorMatchingSnapshot();
+  expect(() => type.validate(undefined)).not.toThrow();
+});
+
+test('throws on value set as object property', () => {
+  const type = schema.object({
+    name: schema.never(),
+    status: schema.string(),
+  });
+
+  expect(() =>
+    type.validate({ name: 'name', status: 'in progress' })
+  ).toThrowErrorMatchingSnapshot();
+
+  expect(() => type.validate({ status: 'in progress' })).not.toThrow();
+  expect(() => type.validate({ name: undefined, status: 'in progress' })).not.toThrow();
+});
+
+test('works for conditional types', () => {
+  const type = schema.object({
+    name: schema.conditional(
+      schema.contextRef('context_value_1'),
+      schema.contextRef('context_value_2'),
+      schema.string(),
+      schema.never()
+    ),
+  });
+
+  expect(
+    type.validate(
+      { name: 'a' },
+      {
+        context_value_1: 0,
+        context_value_2: 0,
+      }
+    )
+  ).toEqual({ name: 'a' });
+
+  expect(() =>
+    type.validate(
+      { name: 'a' },
+      {
+        context_value_1: 0,
+        context_value_2: 1,
+      }
+    )
+  ).toThrowErrorMatchingSnapshot();
+});
+
+test('allows customizing error message', () => {
+  const type = schema.never({ message: 'a rule was deprecated and removed, use [a] instead' });
+
+  expect(() => type.validate(1)).toThrowErrorMatchingSnapshot();
+});

packages/kbn-config-schema/src/types/never_type.ts

@@ -0,0 +1,41 @@
+/*
+ * Licensed to Elasticsearch B.V. under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch B.V. licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import { internals } from '../internals';
+import { Type, TypeOptions } from './type';
+
+export type NeverOptions = TypeOptions<never> & {
+  message?: string;
+};
+
+export class NeverType extends Type<never> {
+  private readonly message?: string;
+  constructor(options: NeverOptions = {}) {
+    const { message, ...typeOptions } = options;
+    super(internals.any().forbidden(), typeOptions);
+    this.message = message;
+  }
+
+  protected handleError(type: string) {
+    switch (type) {
+      case 'any.unknown':
+        return this.message ? this.message : "a value wasn't expected to be present";
+    }
+  }
+}