Replace parentIdMiddleware with expanded Grandparent concept (#3442)

Author: CarsonF

src/common/grandparent.middleware.ts

@@ -0,0 +1,51 @@
+import type { FieldMiddleware } from '@nestjs/graphql';
+import { createGqlPipesParamDecorator } from '@nestjs/graphql/dist/decorators/param.utils.js';
+import { GqlParamtype } from '@nestjs/graphql/dist/enums/gql-paramtype.enum.js';
+import { isRegularObject } from '@seedcompany/common';
+import { ServerException } from './exceptions';
+
+const store = new WeakMap<object, object>();
+
+const get = <T>(value: object): T => {
+  const grandparent = store.get(value);
+  if (!grandparent) {
+    throw new ServerException('Cannot find grandparent');
+  }
+  return grandparent as T;
+};
+
+const middleware: FieldMiddleware = async ({ source, info }, next) => {
+  const value = await next();
+  if (value) {
+    if (!isRegularObject(value)) {
+      throw new ServerException(
+        `Cannot store ${info.parentType.name}.${info.fieldName} for grandparent lookup because it is not an object.`,
+      );
+    }
+    store.set(value, source);
+  }
+  return value;
+};
+
+const PipeableParent = createGqlPipesParamDecorator(GqlParamtype.ROOT);
+
+/**
+ * @example
+ * ```ts
+ * class X {
+ *   @Field({ middleware: [Grandparent.store] })
+ *   y: SecuredY;
+ * }
+ * ```
+ * ```ts
+ * @Resolver(SecuredY)
+ * class Resolver {
+ *   @ResolveField()
+ *   z(
+ *     @Grandparent() x: X
+ *   ) {}
+ * }
+ * ```
+ */
+export const Grandparent = () => PipeableParent({ transform: get });
+Grandparent.store = middleware;

src/common/index.ts

@@ -37,7 +37,7 @@ export * from './optional-field';
 export * from './order.enum';
 export * from './pagination.input';
 export * from './pagination-list';
-export * from './parent-id.middleware';
+export * from './grandparent.middleware';
 export * from './parent-types';
 export * from './poll';
 export * from './resource.dto';

src/common/parent-id.middleware.ts

@@ -7,8 +7,8 @@ import {
   DateTimeField,
   DbLabel,
   type DBNames,
+  Grandparent,
   IntersectTypes,
-  parentIdMiddleware,
   RequiredWhen,
   Resource,
   type ResourceRelationsShape,
@@ -91,7 +91,7 @@ class Engagement extends Interfaces {
   }>;
 
   @Field(() => SecuredEngagementStatus, {
-    middleware: [parentIdMiddleware],
+    middleware: [Grandparent.store],
   })
   @DbLabel('EngagementStatus')
   readonly status: SecuredEngagementStatus;

src/components/engagement/dto/engagement.dto.ts

@@ -1,7 +1,11 @@
 import { Parent, ResolveField, Resolver } from '@nestjs/graphql';
 import { stripIndent } from 'common-tags';
-import { type ParentIdMiddlewareAdditions } from '~/common';
-import { EngagementStatusTransition, SecuredEngagementStatus } from './dto';
+import { Grandparent } from '~/common';
+import {
+  type Engagement,
+  EngagementStatusTransition,
+  SecuredEngagementStatus,
+} from './dto';
 import { EngagementRules } from './engagement.rules';
 
 @Resolver(SecuredEngagementStatus)
@@ -12,15 +16,15 @@ export class EngagementStatusResolver {
     description: 'The available statuses a engagement can be transitioned to.',
   })
   async transitions(
-    @Parent()
-    status: SecuredEngagementStatus & ParentIdMiddlewareAdditions,
+    @Grandparent() eng: Engagement,
+    @Parent() status: SecuredEngagementStatus,
   ): Promise<EngagementStatusTransition[]> {
     if (!status.canRead || !status.canEdit || !status.value) {
       return [];
     }
     return await this.engagementRules.getAvailableTransitions(
-      status.parentId,
-      status.changeset,
+      eng.id,
+      eng.changeset,
     );
   }
 

src/components/engagement/engagement-status.resolver.ts

@@ -3,7 +3,6 @@ import {
   Calculated,
   DbSort,
   IntersectTypes,
-  parentIdMiddleware,
   Resource,
   type ResourceRelationsShape,
   SecuredProperty,
@@ -48,9 +47,7 @@ export class ProgressReport extends Interfaces {
   /** @deprecated */
   declare readonly reportFile: DefinedFile;
 
-  @Field(() => SecuredStatus, {
-    middleware: [parentIdMiddleware],
-  })
+  @Field(() => SecuredStatus)
   @Calculated()
   @DbSort(sortingForEnumIndex(Status))
   readonly status: SecuredStatus;

src/components/progress-report/dto/progress-report.dto.ts

@@ -1,6 +1,5 @@
 import { Parent, ResolveField, Resolver } from '@nestjs/graphql';
 import { stripIndent } from 'common-tags';
-import { type ParentIdMiddlewareAdditions } from '~/common';
 import { SecuredProgressReportStatus } from '../../dto';
 import { ProgressReportWorkflowTransition } from '../dto/workflow-transition.dto';
 import { ProgressReportWorkflowService } from '../progress-report-workflow.service';
@@ -13,7 +12,7 @@ export class ProgressReportTransitionsResolver {
     description: 'The available statuses the report can be transitioned to.',
   })
   async transitions(
-    @Parent() status: SecuredProgressReportStatus & ParentIdMiddlewareAdditions,
+    @Parent() status: SecuredProgressReportStatus,
   ): Promise<ProgressReportWorkflowTransition[]> {
     if (!status.canRead || !status.value) {
       return [];

src/components/progress-report/workflow/resolvers/progress-report-transitions.resolver.ts

@@ -12,9 +12,9 @@ import {
   DbUnique,
   Disabled,
   EnhancedResource,
+  Grandparent,
   IntersectTypes,
   NameField,
-  parentIdMiddleware,
   RequiredWhen,
   Resource,
   type ResourceRelationsShape,
@@ -119,7 +119,7 @@ class Project extends Interfaces {
   readonly departmentId: SecuredStringNullable;
 
   @Field({
-    middleware: [parentIdMiddleware],
+    middleware: [Grandparent.store],
   })
   @DbLabel('ProjectStep')
   @DbSort(sortingForEnumIndex(ProjectStep))

src/components/project/dto/project.dto.ts

@@ -1,10 +1,8 @@
 import { Parent, Query, ResolveField, Resolver } from '@nestjs/graphql';
-import { Loader, type LoaderOf } from '@seedcompany/data-loader';
 import { stripIndent } from 'common-tags';
-import { type ParentIdMiddlewareAdditions, viewOfChangeset } from '~/common';
+import { Grandparent } from '~/common';
 import { SerializedWorkflow } from '../../../workflow/dto';
-import { SecuredProjectStep } from '../../dto';
-import { ProjectLoader } from '../../project.loader';
+import { type Project, SecuredProjectStep } from '../../dto';
 import { ProjectWorkflowTransition } from '../dto';
 import { ProjectWorkflowService } from '../project-workflow.service';
 
@@ -22,16 +20,12 @@ export class ProjectTransitionsResolver {
       'The transitions currently available to execute for this project',
   })
   async transitions(
-    @Parent() status: SecuredProjectStep & ParentIdMiddlewareAdditions,
-    @Loader(ProjectLoader) projects: LoaderOf<ProjectLoader>,
+    @Grandparent() project: Project,
+    @Parent() status: SecuredProjectStep,
   ): Promise<readonly ProjectWorkflowTransition[]> {
     if (!status.canRead || !status.value) {
       return [];
     }
-    const project = await projects.load({
-      id: status.parentId,
-      view: viewOfChangeset(status.changeset),
-    });
     return await this.workflow.getAvailableTransitions(project);
   }