[NP] Allow custom validations in HTTP Routes apart from @kbn/config-schema

docs/development/core/server/kibana-plugin-server.md

@@ -189,4 +189,6 @@ The plugin integrates with the core system via lifecycle events: `setup`<!-- -->
 |  [SavedObjectsClientFactory](./kibana-plugin-server.savedobjectsclientfactory.md) | Describes the factory used to create instances of the Saved Objects Client. |
 |  [SavedObjectsClientWrapperFactory](./kibana-plugin-server.savedobjectsclientwrapperfactory.md) | Describes the factory used to create instances of Saved Objects Client Wrappers. |
 |  [UiSettingsType](./kibana-plugin-server.uisettingstype.md) | UI element type to represent the settings. |
+|  [ValidateFunction](./kibana-plugin-server.validatefunction.md) | Custom validate function (only if @<!-- -->kbn/config-schema is not a valid option in your plugin) |
+|  [ValidateFunctionReturn](./kibana-plugin-server.validatefunctionreturn.md) | Allowed returned format of the custom validate function |
 

docs/development/core/server/kibana-plugin-server.requesthandler.md

@@ -9,7 +9,7 @@ A function executed when route path matched requested resource path. Request han
 <b>Signature:</b>
 
 ```typescript
-export declare type RequestHandler<P extends ObjectType, Q extends ObjectType, B extends ObjectType | Type<Buffer> | Type<Stream>, Method extends RouteMethod = any> = (context: RequestHandlerContext, request: KibanaRequest<TypeOf<P>, TypeOf<Q>, TypeOf<B>, Method>, response: KibanaResponseFactory) => IKibanaResponse<any> | Promise<IKibanaResponse<any>>;
+export declare type RequestHandler<P extends ObjectType | ValidateFunction<unknown>, Q extends ObjectType | ValidateFunction<unknown>, B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>, Method extends RouteMethod = any> = (context: RequestHandlerContext, request: KibanaRequest<ValidatedType<P>, ValidatedType<Q>, ValidatedType<B>, Method>, response: KibanaResponseFactory) => IKibanaResponse<any> | Promise<IKibanaResponse<any>>;
 ```
 
 ## Example

docs/development/core/server/kibana-plugin-server.routeconfig.md

@@ -9,7 +9,7 @@ Route specific configuration.
 <b>Signature:</b>
 
 ```typescript
-export interface RouteConfig<P extends ObjectType, Q extends ObjectType, B extends ObjectType | Type<Buffer> | Type<Stream>, Method extends RouteMethod> 
+export interface RouteConfig<P extends ObjectType | ValidateFunction<unknown>, Q extends ObjectType | ValidateFunction<unknown>, B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>, Method extends RouteMethod> 
 ```
 
 ## Properties

docs/development/core/server/kibana-plugin-server.routeregistrar.md

@@ -9,5 +9,5 @@ Route handler common definition
 <b>Signature:</b>
 
 ```typescript
-export declare type RouteRegistrar<Method extends RouteMethod> = <P extends ObjectType, Q extends ObjectType, B extends ObjectType | Type<Buffer> | Type<Stream>>(route: RouteConfig<P, Q, B, Method>, handler: RequestHandler<P, Q, B, Method>) => void;
+export declare type RouteRegistrar<Method extends RouteMethod> = <P extends ObjectType | ValidateFunction<unknown>, Q extends ObjectType | ValidateFunction<unknown>, B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>>(route: RouteConfig<P, Q, B, Method>, handler: RequestHandler<P, Q, B, Method>) => void;
 ```

docs/development/core/server/kibana-plugin-server.routeschemas.md

@@ -9,7 +9,7 @@ RouteSchemas contains the schemas for validating the different parts of a reques
 <b>Signature:</b>
 
 ```typescript
-export interface RouteSchemas<P extends ObjectType, Q extends ObjectType, B extends ObjectType | Type<Buffer> | Type<Stream>> 
+export interface RouteSchemas<P extends ObjectType | ValidateFunction<unknown>, Q extends ObjectType | ValidateFunction<unknown>, B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>> 
 ```
 
 ## Properties

docs/development/core/server/kibana-plugin-server.validatefunction.md

@@ -0,0 +1,13 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [kibana-plugin-server](./kibana-plugin-server.md) &gt; [ValidateFunction](./kibana-plugin-server.validatefunction.md)
+
+## ValidateFunction type
+
+Custom validate function (only if @<!-- -->kbn/config-schema is not a valid option in your plugin)
+
+<b>Signature:</b>
+
+```typescript
+export declare type ValidateFunction<T> = (data: any) => ValidateFunctionReturn<T>;
+```

docs/development/core/server/kibana-plugin-server.validatefunctionreturn.md

@@ -0,0 +1,19 @@
+<!-- Do not edit this file. It is automatically generated by API Documenter. -->
+
+[Home](./index.md) &gt; [kibana-plugin-server](./kibana-plugin-server.md) &gt; [ValidateFunctionReturn](./kibana-plugin-server.validatefunctionreturn.md)
+
+## ValidateFunctionReturn type
+
+Allowed returned format of the custom validate function
+
+<b>Signature:</b>
+
+```typescript
+export declare type ValidateFunctionReturn<T> = {
+    value: T;
+    error?: undefined;
+} | {
+    value?: undefined;
+    error: SchemaTypeError;
+};
+```

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

@@ -59,6 +59,7 @@ import {
 
 export { ObjectType, TypeOf, Type };
 export { ByteSizeValue } from './byte_size_value';
+export { SchemaTypeError, ValidationError } from './errors';
 
 function any(options?: TypeOptions<any>) {
   return new AnyType(options);

src/core/server/http/index.ts

@@ -51,6 +51,8 @@ export {
   RouteConfigOptionsBody,
   RouteContentType,
   validBodyOutput,
+  ValidateFunctionReturn,
+  ValidateFunction,
 } from './router';
 export { BasePathProxyServer } from './base_path_proxy_server';
 export { OnPreAuthHandler, OnPreAuthToolkit } from './lifecycle/on_pre_auth';

src/core/server/http/router/error_wrapper.ts

@@ -18,19 +18,25 @@
  */
 
 import Boom from 'boom';
-import { ObjectType, TypeOf } from '@kbn/config-schema';
+import { ObjectType, Type } from '@kbn/config-schema';
+import { Stream } from 'stream';
 import { KibanaRequest } from './request';
 import { KibanaResponseFactory } from './response';
 import { RequestHandler } from './router';
 import { RequestHandlerContext } from '../../../server';
 import { RouteMethod } from './route';
+import { ValidateFunction, ValidatedType } from './validator';
 
-export const wrapErrors = <P extends ObjectType, Q extends ObjectType, B extends ObjectType>(
+export const wrapErrors = <
+  P extends ObjectType | ValidateFunction<unknown>,
+  Q extends ObjectType | ValidateFunction<unknown>,
+  B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>
+>(
   handler: RequestHandler<P, Q, B, RouteMethod>
 ): RequestHandler<P, Q, B, RouteMethod> => {
   return async (
     context: RequestHandlerContext,
-    request: KibanaRequest<TypeOf<P>, TypeOf<Q>, TypeOf<B>, RouteMethod>,
+    request: KibanaRequest<ValidatedType<P>, ValidatedType<Q>, ValidatedType<B>, RouteMethod>,
     response: KibanaResponseFactory
   ) => {
     try {

src/core/server/http/router/index.ts

@@ -55,3 +55,5 @@ export {
 } from './response';
 
 export { IKibanaSocket } from './socket';
+
+export { ValidateFunctionReturn, ValidateFunction } from './validator';

src/core/server/http/router/request.test.ts

@@ -18,6 +18,7 @@
  */
 import { KibanaRequest } from './request';
 import { httpServerMock } from '../http_server.mocks';
+import { schema, SchemaTypeError } from '@kbn/config-schema';
 
 describe('KibanaRequest', () => {
   describe('get all headers', () => {
@@ -64,4 +65,52 @@ describe('KibanaRequest', () => {
       });
     });
   });
+
+  describe('RouteSchema type inferring', () => {
+    it('should work with config-schema', () => {
+      const body = new Buffer('body!');
+      const request = httpServerMock.createRawRequest({
+        params: { id: 'params' },
+        query: { search: 'query' },
+        payload: body,
+      });
+      const kibanaRequest = KibanaRequest.from(request, {
+        params: schema.object({ id: schema.string() }),
+        query: schema.object({ search: schema.string() }),
+        body: schema.buffer(),
+      });
+      expect(kibanaRequest.params).toStrictEqual({ id: 'params' });
+      expect(kibanaRequest.params.id.toUpperCase()).toEqual('PARAMS'); // infers it's a string
+      expect(kibanaRequest.query).toStrictEqual({ search: 'query' });
+      expect(kibanaRequest.query.search.toUpperCase()).toEqual('QUERY'); // infers it's a string
+      expect(kibanaRequest.body).toEqual(body);
+      expect(kibanaRequest.body.byteLength).toBeGreaterThan(0); // infers it's a buffer
+    });
+
+    it('should work with ValidationFunction', () => {
+      const body = new Buffer('body!');
+      const request = httpServerMock.createRawRequest({
+        params: { id: 'params' },
+        query: { search: 'query' },
+        payload: body,
+      });
+      const kibanaRequest = KibanaRequest.from(request, {
+        params: schema.object({ id: schema.string() }),
+        query: schema.object({ search: schema.string() }),
+        body: data => {
+          if (Buffer.isBuffer(data)) {
+            return { value: data };
+          } else {
+            return { error: new SchemaTypeError('It should be a Buffer', []) };
+          }
+        },
+      });
+      expect(kibanaRequest.params).toStrictEqual({ id: 'params' });
+      expect(kibanaRequest.params.id.toUpperCase()).toEqual('PARAMS'); // infers it's a string
+      expect(kibanaRequest.query).toStrictEqual({ search: 'query' });
+      expect(kibanaRequest.query.search.toUpperCase()).toEqual('QUERY'); // infers it's a string
+      expect(kibanaRequest.body).toEqual(body);
+      expect(kibanaRequest.body.byteLength).toBeGreaterThan(0); // infers it's a buffer
+    });
+  });
 });

src/core/server/http/router/request.ts

@@ -20,13 +20,14 @@
 import { Url } from 'url';
 import { Request } from 'hapi';
 
-import { ObjectType, Type, TypeOf } from '@kbn/config-schema';
+import { ObjectType, Type } from '@kbn/config-schema';
 
 import { Stream } from 'stream';
 import { deepFreeze, RecursiveReadonly } from '../../../utils';
 import { Headers } from './headers';
 import { RouteMethod, RouteSchemas, RouteConfigOptions, validBodyOutput } from './route';
 import { KibanaSocket, IKibanaSocket } from './socket';
+import { validate, ValidateFunction, ValidatedType } from './validator';
 
 const requestSymbol = Symbol('request');
 
@@ -71,9 +72,9 @@ export class KibanaRequest<
    * @internal
    */
   public static from<
-    P extends ObjectType,
-    Q extends ObjectType,
-    B extends ObjectType | Type<Buffer> | Type<Stream>
+    P extends ObjectType | ValidateFunction<any>,
+    Q extends ObjectType | ValidateFunction<any>,
+    B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<any>
   >(req: Request, routeSchemas?: RouteSchemas<P, Q, B>, withoutSecretHeaders: boolean = true) {
     const requestParts = KibanaRequest.validate(req, routeSchemas);
     return new KibanaRequest(
@@ -92,39 +93,39 @@ export class KibanaRequest<
    * @internal
    */
   private static validate<
-    P extends ObjectType,
-    Q extends ObjectType,
-    B extends ObjectType | Type<Buffer> | Type<Stream>
+    P extends ObjectType | ValidateFunction<any>,
+    Q extends ObjectType | ValidateFunction<any>,
+    B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<any>
   >(
     req: Request,
     routeSchemas: RouteSchemas<P, Q, B> | undefined
   ): {
-    params: TypeOf<P>;
-    query: TypeOf<Q>;
-    body: TypeOf<B>;
+    params: ValidatedType<P>;
+    query: ValidatedType<Q>;
+    body: ValidatedType<B>;
   } {
     if (routeSchemas === undefined) {
       return {
-        body: {},
-        params: {},
-        query: {},
+        params: {} as ValidatedType<P>,
+        query: {} as ValidatedType<Q>,
+        body: {} as ValidatedType<B>,
       };
     }
 
     const params =
       routeSchemas.params === undefined
-        ? {}
-        : routeSchemas.params.validate(req.params, {}, 'request params');
+        ? ({} as ValidatedType<P>)
+        : validate<ValidatedType<P>>(routeSchemas.params, req.params, 'request params');
 
     const query =
       routeSchemas.query === undefined
-        ? {}
-        : routeSchemas.query.validate(req.query, {}, 'request query');
+        ? ({} as ValidatedType<Q>)
+        : validate<ValidatedType<Q>>(routeSchemas.query, req.query, 'request query');
 
     const body =
       routeSchemas.body === undefined
-        ? {}
-        : routeSchemas.body.validate(req.payload, {}, 'request body');
+        ? ({} as ValidatedType<B>)
+        : validate<ValidatedType<B>>(routeSchemas.body as any, req.payload, 'request body');
 
     return { query, params, body };
   }

src/core/server/http/router/route.ts

@@ -19,6 +19,7 @@
 
 import { ObjectType, Type } from '@kbn/config-schema';
 import { Stream } from 'stream';
+import { ValidateFunction } from './validator';
 
 /**
  * The set of common HTTP methods supported by Kibana routing.
@@ -125,9 +126,9 @@ export interface RouteConfigOptions<Method extends RouteMethod> {
  * @public
  */
 export interface RouteConfig<
-  P extends ObjectType,
-  Q extends ObjectType,
-  B extends ObjectType | Type<Buffer> | Type<Stream>,
+  P extends ObjectType | ValidateFunction<unknown>,
+  Q extends ObjectType | ValidateFunction<unknown>,
+  B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>,
   Method extends RouteMethod
 > {
   /**
@@ -215,9 +216,9 @@ export interface RouteConfig<
  * @public
  */
 export interface RouteSchemas<
-  P extends ObjectType,
-  Q extends ObjectType,
-  B extends ObjectType | Type<Buffer> | Type<Stream>
+  P extends ObjectType | ValidateFunction<unknown>,
+  Q extends ObjectType | ValidateFunction<unknown>,
+  B extends ObjectType | Type<Buffer> | Type<Stream> | ValidateFunction<unknown>
 > {
   params?: P;
   query?: Q;