feat(core): sets default response type as null; maps undefined to nul…

…l on services

packages/core/src/application/index.ts

@@ -7,7 +7,7 @@ import {
   ApplicationServices
 } from '~/types';
 import { validate, traverse, isElementService, atPath } from '~/inspect';
-import { addInterceptErrors } from './intercept-errors';
+import { addInterceptResponse } from './intercept-response';
 import { mergeIntercepts } from './merge-intercepts';
 import { handleChildren } from './handle-children';
 import { getRoutes } from './get-routes';
@@ -35,9 +35,10 @@ export type ApplicationCreateMapFn<I = any, O = any, C = any> = (
 
 /**
  * Validates and prepares a collection to be used:
- * - Adds `ServerError` and `ClientError` error types, if non existent, to the collection declaration.
- * - Handles children adequately according to whether they have children services.
- * - Merges service intercepts into each route resolver, and makes them fail with `PublicError`s, if they don't already do.
+ * - Merges service intercepts into each route resolver.
+ * - Ensures services fail with a `PublicError` and resolve with `null` for empty responses.
+ * - Ensures `ServerError` and `ClientError` error types exist on the collection declaration.
+ * - Names and lifts inline types to the collection root if they have children services.
  */
 export function application<T extends CollectionTreeImplementation>(
   collection: T,
@@ -59,7 +60,7 @@ export function application<T extends CollectionTreeImplementation>(
   let tree: CollectionTreeImplementation = collection;
   if (opts.validate) validate(tree, { as: 'implementation' });
   tree = handleChildren(tree, opts.children ? 'lift' : 'remove');
-  tree = addInterceptErrors(tree);
+  tree = addInterceptResponse(tree);
   tree = mergeIntercepts(tree);
 
   const declaration = toDeclaration(tree);

packages/core/src/application/intercept-errors.ts → packages/core/src/application/intercept-response.ts

@@ -1,10 +1,10 @@
 import { CollectionTreeImplementation } from '~/types';
-import { catchError } from 'rxjs/operators';
+import { catchError, map } from 'rxjs/operators';
 import { throwError } from 'rxjs';
 import { PublicError, CollectionError } from '~/errors';
 import { error, intercepts, intercept } from '~/create';
 
-export function addInterceptErrors(
+export function addInterceptResponse(
   collection: CollectionTreeImplementation
 ): CollectionTreeImplementation {
   const errors = {
@@ -27,6 +27,7 @@ export function addInterceptErrors(
         ),
         factory: () => (data, context, info, next) => {
           return next(data).pipe(
+            map((value) => (value === undefined ? null : value)),
             catchError((err) =>
               throwError(
                 err instanceof PublicError

packages/core/src/create/implement/services/services.ts

@@ -92,10 +92,10 @@ function parseTypes(types: ServiceInputTypes = {}): ServiceTypesImplementation {
     request:
       isElement(types.request) || typeof types.request === 'string'
         ? types.request
-        : request({ schema: types.request || {} }),
+        : request({ schema: types.request || { type: 'object' } }),
     response:
       isElement(types.response) || typeof types.response === 'string'
         ? types.response
-        : response({ schema: types.response || {} })
+        : response({ schema: types.response || { type: 'null' } })
   };
 }

packages/core/src/inspect/validate.ts

@@ -3,7 +3,8 @@ import { normalize } from '~/transform/normalize';
 import { isTreeImplementation } from './is';
 
 // TODO: validate collection object (ajv) + check schemas are valid
-
+// TODO: children services must have a request schema equal or as a subset of the type they belong to
+// TODO: all request types must be of type object
 export interface ValidateInspectOptions {
   /**
    * If specified, it will also throw if the collection is not a full implementation or solely a declaration, in each case. Default: `null`.