V2 centralize relation optimistic logic (#15552)

# Introduction This PR aims to deprecate having to manually handle optimistic side effect foreign key addition in the whole v2 experience. This PR implements the strong basis + builder refactor of the optimistic computation of a given flat entity maps with its related flat entity maps ( runner needs a small refactor on actions type definition first ) Flat entity maps updates through mutations are now only scoped to the generic entity builder ( very isolated ) ## What's next - Refactor actions v2 type definition to gain grain over `metadataName` and action operation ( `create` `delete` `update` ). from `{type: 'create_view_field'}` to `{metadataName: 'view_field', type: 'create' }` - Use new optimistic tool computation tools - Only invalidate impacted flat maps cache ## New tools Strictly dynamically typed new flat entity maps tools - `addFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrow` - `deleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrow` ## Unit test Adding basic unit testing coverage to introduced tools ## `FlatEntityValidationArgs` From ```ts export type FlatEntityValidationArgs<T extends AllMetadataName> = { flatEntityToValidate: MetadataFlatEntity<T>; optimisticFlatEntityMaps: MetadataFlatEntityMaps<T>; mutableDependencyOptimisticFlatEntityMaps: MetadataValidationRelatedFlatEntityMaps<T>; workspaceId: string; remainingFlatEntityMapsToValidate: MetadataFlatEntityMaps<T>; buildOptions: WorkspaceMigrationBuilderOptions; }; ``` To ```ts export type FlatEntityValidationArgs<T extends AllMetadataName> = { flatEntityToValidate: MetadataFlatEntity<T>; optimisticFlatEntityMapsAndRelatedFlatEntityMaps: MetadataFlatEntityAndRelatedFlatEntityMapsForValidation<T>; workspaceId: string; remainingFlatEntityMapsToValidate: MetadataFlatEntityMaps<T>; buildOptions: WorkspaceMigrationBuilderOptions; }; ```
2025-11-04 12:28:28 +01:00
parent 281070423f
commit 3514054235
39 changed files with 946 additions and 807 deletions
@@ -0,0 +1,94 @@
+import { FieldMetadataType } from 'twenty-shared/types';
+
+import { createEmptyFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/constant/create-empty-flat-entity-maps.constant';
+import { type MetadataFlatEntityAndRelatedFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-types.type';
+import { addFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/add-flat-entity-to-flat-entity-and-related-entity-maps-through-mutation-or-throw.util';
+import { addFlatEntityToFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/add-flat-entity-to-flat-entity-maps-or-throw.util';
+import { getFlatFieldMetadataMock } from 'src/engine/metadata-modules/flat-field-metadata/__mocks__/get-flat-field-metadata.mock';
+import { type FlatFieldMetadata } from 'src/engine/metadata-modules/flat-field-metadata/types/flat-field-metadata.type';
+import { getFlatObjectMetadataMock } from 'src/engine/metadata-modules/flat-object-metadata/__mocks__/get-flat-object-metadata.mock';
+import { type FlatObjectMetadata } from 'src/engine/metadata-modules/flat-object-metadata/types/flat-object-metadata.type';
+import { type FlatView } from 'src/engine/metadata-modules/flat-view/types/flat-view.type';
+
+describe('addFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrow', () => {
+  it('should add a view and update related objectMetadata with viewId', () => {
+    const objectMetadataId = 'object-1';
+    const viewId = 'view-1';
+    const applicationId = '20202020-f3ad-452e-b5b6-2d49d3ea88b1';
+    const workspaceId = '20202020-bc64-4148-8a79-b3144f743694';
+    const mockObjectMetadata = getFlatObjectMetadataMock({
+      id: objectMetadataId,
+      universalIdentifier: 'object-universal-1',
+      viewIds: [],
+      fieldMetadataIds: [],
+      workspaceId,
+      imageIdentifierFieldMetadataId: '20202020-9d65-415f-b0e1-216a2e257ea4',
+      labelIdentifierFieldMetadataId: '20202020-1a62-405c-87fa-4d4fd215851b',
+      applicationId,
+    });
+
+    const mockFieldMEtadata = getFlatFieldMetadataMock({
+      objectMetadataId,
+      id: '202020-71a3-4856-a3d0-d08cea0ecec6',
+      type: FieldMetadataType.DATE,
+      workspaceId,
+      applicationId,
+      universalIdentifier: 'field-universal-1',
+      viewFieldIds: [],
+      viewGroupIds: [],
+      viewFilterIds: [],
+      calendarViewIds: [],
+    });
+
+    const mockView: Pick<FlatView, 'id'> & Partial<FlatView> = {
+      id: viewId,
+      workspaceId,
+      universalIdentifier: 'view-universal-1',
+      objectMetadataId: objectMetadataId,
+      viewFieldIds: [],
+      viewFilterIds: [],
+      viewGroupIds: [],
+      applicationId,
+      calendarFieldMetadataId: mockFieldMEtadata.id,
+    };
+
+    const flatEntityAndRelatedMapsToMutate: MetadataFlatEntityAndRelatedFlatEntityMaps<'view'> =
+      {
+        flatFieldMetadataMaps: addFlatEntityToFlatEntityMapsOrThrow({
+          flatEntity: mockFieldMEtadata,
+          flatEntityMaps: createEmptyFlatEntityMaps(),
+        }),
+        flatObjectMetadataMaps: addFlatEntityToFlatEntityMapsOrThrow({
+          flatEntity: mockObjectMetadata,
+          flatEntityMaps: createEmptyFlatEntityMaps(),
+        }),
+        flatViewMaps: createEmptyFlatEntityMaps(),
+      };
+
+    addFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrow({
+      metadataName: 'view',
+      flatEntity: mockView as FlatView,
+      flatEntityAndRelatedMapsToMutate,
+    });
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatViewMaps.byId[mockView.id],
+    ).toMatchObject(mockView);
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatObjectMetadataMaps.byId[
+        objectMetadataId
+      ],
+    ).toMatchObject<Partial<FlatObjectMetadata>>({
+      viewIds: [mockView.id],
+    });
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatFieldMetadataMaps.byId[
+        mockFieldMEtadata.id
+      ],
+    ).toMatchObject<Partial<FlatFieldMetadata>>({
+      calendarViewIds: [mockView.id],
+    });
+  });
+});
@@ -0,0 +1,104 @@
+import { FieldMetadataType } from 'twenty-shared/types';
+
+import { createEmptyFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/constant/create-empty-flat-entity-maps.constant';
+import { type MetadataFlatEntityAndRelatedFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-types.type';
+import { addFlatEntityToFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/add-flat-entity-to-flat-entity-maps-or-throw.util';
+import { deleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/delete-flat-entity-from-flat-entity-and-related-entity-maps-through-mutation-or-throw.util';
+import { getFlatFieldMetadataMock } from 'src/engine/metadata-modules/flat-field-metadata/__mocks__/get-flat-field-metadata.mock';
+import { type FlatFieldMetadata } from 'src/engine/metadata-modules/flat-field-metadata/types/flat-field-metadata.type';
+import { getFlatObjectMetadataMock } from 'src/engine/metadata-modules/flat-object-metadata/__mocks__/get-flat-object-metadata.mock';
+import { type FlatObjectMetadata } from 'src/engine/metadata-modules/flat-object-metadata/types/flat-object-metadata.type';
+import { type FlatView } from 'src/engine/metadata-modules/flat-view/types/flat-view.type';
+
+describe('deleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrow', () => {
+  it('should delete a view and update related objectMetadata and fieldMetadata by removing viewId', () => {
+    const objectMetadataId = 'object-1';
+    const viewId = 'view-1';
+    const applicationId = '20202020-f3ad-452e-b5b6-2d49d3ea88b1';
+    const workspaceId = '20202020-bc64-4148-8a79-b3144f743694';
+
+    const mockObjectMetadata = getFlatObjectMetadataMock({
+      id: objectMetadataId,
+      universalIdentifier: 'object-universal-1',
+      viewIds: [viewId, 'something-else'],
+      fieldMetadataIds: [],
+      workspaceId,
+      imageIdentifierFieldMetadataId: '20202020-9d65-415f-b0e1-216a2e257ea4',
+      labelIdentifierFieldMetadataId: '20202020-1a62-405c-87fa-4d4fd215851b',
+      applicationId,
+    });
+
+    const mockFieldMetadata = getFlatFieldMetadataMock({
+      objectMetadataId,
+      id: '20202020-4087-423b-852a-91f91acf2df2',
+      type: FieldMetadataType.DATE,
+      universalIdentifier: 'field-universal-1',
+      viewFieldIds: [],
+      viewGroupIds: [],
+      viewFilterIds: [],
+      workspaceId,
+      calendarViewIds: [viewId],
+      applicationId,
+    });
+
+    const mockView: Partial<FlatView> = {
+      id: viewId,
+      universalIdentifier: 'view-universal-1',
+      objectMetadataId: objectMetadataId,
+      viewFieldIds: [],
+      viewFilterIds: [],
+      viewGroupIds: [],
+      workspaceId,
+      calendarFieldMetadataId: mockFieldMetadata.id,
+      createdAt: new Date('2024-01-01'),
+      updatedAt: new Date('2024-01-01'),
+      icon: 'icon',
+      isCompact: false,
+      name: 'View Name',
+      position: 0,
+      applicationId,
+    };
+
+    const flatEntityAndRelatedMapsToMutate: MetadataFlatEntityAndRelatedFlatEntityMaps<'view'> =
+      {
+        flatFieldMetadataMaps: addFlatEntityToFlatEntityMapsOrThrow({
+          flatEntity: mockFieldMetadata,
+          flatEntityMaps: createEmptyFlatEntityMaps(),
+        }),
+        flatObjectMetadataMaps: addFlatEntityToFlatEntityMapsOrThrow({
+          flatEntity: mockObjectMetadata,
+          flatEntityMaps: createEmptyFlatEntityMaps(),
+        }),
+        flatViewMaps: addFlatEntityToFlatEntityMapsOrThrow({
+          flatEntity: mockView as FlatView,
+          flatEntityMaps: createEmptyFlatEntityMaps(),
+        }),
+      };
+
+    deleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrow({
+      metadataName: 'view',
+      flatEntity: mockView as FlatView,
+      flatEntityAndRelatedMapsToMutate,
+    });
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatViewMaps.byId[viewId],
+    ).toBeUndefined();
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatObjectMetadataMaps.byId[
+        objectMetadataId
+      ],
+    ).toMatchObject<Partial<FlatObjectMetadata>>({
+      viewIds: ['something-else'],
+    });
+
+    expect(
+      flatEntityAndRelatedMapsToMutate.flatFieldMetadataMaps.byId[
+        mockFieldMetadata.id
+      ],
+    ).toMatchObject<Partial<FlatFieldMetadata>>({
+      calendarViewIds: [],
+    });
+  });
+});
@@ -1,90 +0,0 @@
-import { type AllMetadataName } from 'twenty-shared/metadata';
-
-import { ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY } from 'src/engine/metadata-modules/flat-entity/constant/all-metadata-many-to-one-relations.constant';
-import {
-  FlatEntityMapsException,
-  FlatEntityMapsExceptionCode,
-} from 'src/engine/metadata-modules/flat-entity/exceptions/flat-entity-maps.exception';
-import { type MetadataFlatEntity } from 'src/engine/metadata-modules/flat-entity/types/metadata-flat-entity.type';
-import { type MetadataFlatEntityAndRelatedFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-types.type';
-import { addFlatEntityToFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/add-flat-entity-to-flat-entity-maps-or-throw.util';
-import { findFlatEntityByIdInFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-id-in-flat-entity-maps-or-throw.util';
-import { getMetadataFlatEntityMapsKey } from 'src/engine/metadata-modules/flat-entity/utils/get-metadata-flat-entity-maps-key.util';
-
-type AddFlatEntityToFlatEntityAndRelatedEntityMapsOrThrowArgs<
-  T extends AllMetadataName,
-> = {
-  metadataName: T;
-  flatEntity: MetadataFlatEntity<T>;
-  flatEntityAndRelatedMaps: MetadataFlatEntityAndRelatedFlatEntityMaps<T>;
-};
-export const addFlatEntityToFlatEntityAndRelatedEntityMapsOrThrow = <
-  T extends AllMetadataName,
->({
-  metadataName,
-  flatEntity,
-  flatEntityAndRelatedMaps: initialFlatEntityAndRelatedMaps,
-}: AddFlatEntityToFlatEntityAndRelatedEntityMapsOrThrowArgs<T>): MetadataFlatEntityAndRelatedFlatEntityMaps<T> => {
-  const flatEntityMapsKey: keyof MetadataFlatEntityAndRelatedFlatEntityMaps<T> =
-    getMetadataFlatEntityMapsKey(metadataName);
-
-  const updatedFlatEntityMaps = addFlatEntityToFlatEntityMapsOrThrow({
-    flatEntity,
-    flatEntityMaps: initialFlatEntityAndRelatedMaps[flatEntityMapsKey],
-  });
-
-  // TODO refactor
-  const manyToOneRelatedMetadataName = Object.entries(
-    ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY[metadataName],
-  );
-
-  return manyToOneRelatedMetadataName.reduce(
-    (flatEntityAndRelatedMaps, [relatedMetadataName, foreignKey]) => {
-      const relatedFlatEntityMapsKey = getMetadataFlatEntityMapsKey(
-        relatedMetadataName as AllMetadataName,
-      );
-      const relatedFLatEntityMetadataMaps =
-        flatEntityAndRelatedMaps[relatedFlatEntityMapsKey];
-
-      const relatedFlatEntity = findFlatEntityByIdInFlatEntityMapsOrThrow({
-        flatEntityId: flatEntity[
-          foreignKey as keyof MetadataFlatEntity<T>
-        ] as string,
-        flatEntityMaps: relatedFLatEntityMetadataMaps,
-      });
-
-      const foreignKeyAggregatorProperty = `${metadataName}Ids`;
-
-      if (
-        !Object.prototype.hasOwnProperty.call(
-          relatedFlatEntity,
-          foreignKeyAggregatorProperty,
-        )
-      ) {
-        throw new FlatEntityMapsException(
-          'Should never occur, invalid cached format',
-          FlatEntityMapsExceptionCode.ENTITY_MALFORMED,
-        );
-      }
-
-      const updatedRelatedFlatEntityMetadataMaps = {
-        ...relatedFlatEntity,
-        [foreignKeyAggregatorProperty]: [
-          ...(relatedFlatEntity[
-            foreignKeyAggregatorProperty as keyof MetadataFlatEntity<T>
-          ] as string[]),
-          flatEntity.id,
-        ],
-      };
-
-      return {
-        ...flatEntityAndRelatedMaps,
-        [relatedFlatEntityMapsKey]: updatedRelatedFlatEntityMetadataMaps,
-      };
-    },
-    {
-      ...initialFlatEntityAndRelatedMaps,
-      [flatEntityMapsKey]: updatedFlatEntityMaps,
-    },
-  );
-};
@@ -0,0 +1,101 @@
+import { type AllMetadataName } from 'twenty-shared/metadata';
+import { isDefined } from 'twenty-shared/utils';
+
+import { ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY } from 'src/engine/metadata-modules/flat-entity/constant/all-metadata-many-to-one-relations.constant';
+import {
+  FlatEntityMapsException,
+  FlatEntityMapsExceptionCode,
+} from 'src/engine/metadata-modules/flat-entity/exceptions/flat-entity-maps.exception';
+import { type FlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/flat-entity-maps.type';
+import { type MetadataFlatEntity } from 'src/engine/metadata-modules/flat-entity/types/metadata-flat-entity.type';
+import { type MetadataRelatedFlatEntityMapsKeys } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-flat-entity-maps-keys.type';
+import { type MetadataFlatEntityAndRelatedFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-types.type';
+import { findFlatEntityByIdInFlatEntityMapsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-id-in-flat-entity-maps-or-throw.util';
+import { getMetadataFlatEntityMapsKey } from 'src/engine/metadata-modules/flat-entity/utils/get-metadata-flat-entity-maps-key.util';
+import { addFlatEntityToFlatEntityMapsThroughMutationOrThrow } from 'src/engine/workspace-manager/workspace-migration-v2/utils/add-flat-entity-to-flat-entity-maps-through-mutation-or-throw.util';
+import { replaceFlatEntityInFlatEntityMapsThroughMutationOrThrow } from 'src/engine/workspace-manager/workspace-migration-v2/utils/replace-flat-entity-in-flat-entity-maps-through-mutation-or-throw.util';
+
+type AddFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrowArgs<
+  T extends AllMetadataName,
+> = {
+  metadataName: T;
+  flatEntity: MetadataFlatEntity<T>;
+  flatEntityAndRelatedMapsToMutate: MetadataFlatEntityAndRelatedFlatEntityMaps<T>;
+};
+export const addFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrow =
+  <T extends AllMetadataName>({
+    metadataName,
+    flatEntity,
+    flatEntityAndRelatedMapsToMutate,
+  }: AddFlatEntityToFlatEntityAndRelatedEntityMapsThroughMutationOrThrowArgs<T>) => {
+    const flatEntityMapsKey = getMetadataFlatEntityMapsKey(metadataName);
+
+    addFlatEntityToFlatEntityMapsThroughMutationOrThrow({
+      flatEntity,
+      flatEntityMapsToMutate:
+        flatEntityAndRelatedMapsToMutate[flatEntityMapsKey],
+    });
+
+    const manyToOneRelatedMetadataName = Object.entries(
+      ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY[metadataName],
+    ) as Array<
+      [
+        keyof MetadataFlatEntity<T>,
+        {
+          metadataName: AllMetadataName;
+          flatEntityForeignKeyAggregator: keyof MetadataFlatEntity<AllMetadataName>;
+        },
+      ]
+    >;
+
+    for (const [
+      foreignKey,
+      { metadataName: relatedMetadataName, flatEntityForeignKeyAggregator },
+    ] of manyToOneRelatedMetadataName) {
+      const relatedFlatEntityMapsKey =
+        getMetadataFlatEntityMapsKey(relatedMetadataName);
+      const relatedFlatEntityMetadataMaps = flatEntityAndRelatedMapsToMutate[
+        relatedFlatEntityMapsKey as MetadataRelatedFlatEntityMapsKeys<T>
+      ] as FlatEntityMaps<MetadataFlatEntity<typeof relatedMetadataName>>;
+
+      const flatEntityRelatedEntityForeignKeyValue = flatEntity[foreignKey] as
+        | string
+        | undefined;
+
+      if (!isDefined(flatEntityRelatedEntityForeignKeyValue)) {
+        continue;
+      }
+
+      const relatedFlatEntity = findFlatEntityByIdInFlatEntityMapsOrThrow({
+        flatEntityId: flatEntityRelatedEntityForeignKeyValue,
+        flatEntityMaps: relatedFlatEntityMetadataMaps,
+      });
+
+      if (
+        !Object.prototype.hasOwnProperty.call(
+          relatedFlatEntity,
+          flatEntityForeignKeyAggregator,
+        )
+      ) {
+        throw new FlatEntityMapsException(
+          `Should never occur, invalid flat entity typing. flat ${metadataName} should contain ${flatEntityForeignKeyAggregator}`,
+          FlatEntityMapsExceptionCode.ENTITY_MALFORMED,
+        );
+      }
+
+      const updatedRelatedEntity = {
+        ...relatedFlatEntity,
+        [flatEntityForeignKeyAggregator]: [
+          ...(relatedFlatEntity[
+            flatEntityForeignKeyAggregator
+          ] as unknown as string[]),
+          flatEntity.id,
+        ],
+      };
+
+      replaceFlatEntityInFlatEntityMapsThroughMutationOrThrow({
+        flatEntity: updatedRelatedEntity,
+        flatEntityMapsToMutate: relatedFlatEntityMetadataMaps,
+      });
+    }
+  };
@@ -0,0 +1,107 @@
+import { type AllMetadataName } from 'twenty-shared/metadata';
+import { isDefined } from 'twenty-shared/utils';
+
+import { ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY } from 'src/engine/metadata-modules/flat-entity/constant/all-metadata-many-to-one-relations.constant';
+import {
+  FlatEntityMapsException,
+  FlatEntityMapsExceptionCode,
+} from 'src/engine/metadata-modules/flat-entity/exceptions/flat-entity-maps.exception';
+import { type FlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/flat-entity-maps.type';
+import { type MetadataFlatEntity } from 'src/engine/metadata-modules/flat-entity/types/metadata-flat-entity.type';
+import { type MetadataRelatedFlatEntityMapsKeys } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-flat-entity-maps-keys.type';
+import { type MetadataFlatEntityAndRelatedFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/types/metadata-related-types.type';
+import { findFlatEntityByIdInFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-id-in-flat-entity-maps.util';
+import { getMetadataFlatEntityMapsKey } from 'src/engine/metadata-modules/flat-entity/utils/get-metadata-flat-entity-maps-key.util';
+import { deleteFlatEntityFromFlatEntityMapsThroughMutationOrThrow } from 'src/engine/workspace-manager/workspace-migration-v2/utils/delete-flat-entity-from-flat-entity-maps-through-mutation-or-throw.util';
+import { replaceFlatEntityInFlatEntityMapsThroughMutationOrThrow } from 'src/engine/workspace-manager/workspace-migration-v2/utils/replace-flat-entity-in-flat-entity-maps-through-mutation-or-throw.util';
+
+type DeleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrowArgs<
+  T extends AllMetadataName,
+> = {
+  metadataName: T;
+  flatEntity: MetadataFlatEntity<T>;
+  flatEntityAndRelatedMapsToMutate: MetadataFlatEntityAndRelatedFlatEntityMaps<T>;
+};
+export const deleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrow =
+  <T extends AllMetadataName>({
+    metadataName,
+    flatEntity,
+    flatEntityAndRelatedMapsToMutate,
+  }: DeleteFlatEntityFromFlatEntityAndRelatedEntityMapsThroughMutationOrThrowArgs<T>) => {
+    const flatEntityMapsKey = getMetadataFlatEntityMapsKey(metadataName);
+
+    deleteFlatEntityFromFlatEntityMapsThroughMutationOrThrow<
+      MetadataFlatEntity<T>
+    >({
+      entityToDeleteId: flatEntity.id,
+      flatEntityMapsToMutate:
+        flatEntityAndRelatedMapsToMutate[flatEntityMapsKey],
+    });
+
+    const manyToOneRelatedMetadataName = Object.entries(
+      ALL_METADATA_RELATED_METADATA_BY_FOREIGN_KEY[metadataName],
+    ) as Array<
+      [
+        keyof MetadataFlatEntity<T>,
+        {
+          metadataName: AllMetadataName;
+          flatEntityForeignKeyAggregator: keyof MetadataFlatEntity<AllMetadataName>;
+        },
+      ]
+    >;
+
+    for (const [
+      foreignKey,
+      { metadataName: relatedMetadataName, flatEntityForeignKeyAggregator },
+    ] of manyToOneRelatedMetadataName) {
+      const relatedFlatEntityMapsKey =
+        getMetadataFlatEntityMapsKey(relatedMetadataName);
+
+      const relatedFlatEntityMetadataMaps = flatEntityAndRelatedMapsToMutate[
+        relatedFlatEntityMapsKey as MetadataRelatedFlatEntityMapsKeys<T>
+      ] as FlatEntityMaps<MetadataFlatEntity<typeof relatedMetadataName>>;
+
+      const flatEntityRelatedEntityForeignKeyValue = flatEntity[foreignKey] as
+        | string
+        | undefined;
+
+      if (!isDefined(flatEntityRelatedEntityForeignKeyValue)) {
+        continue;
+      }
+
+      const relatedFlatEntity = findFlatEntityByIdInFlatEntityMaps({
+        flatEntityId: flatEntityRelatedEntityForeignKeyValue,
+        flatEntityMaps: relatedFlatEntityMetadataMaps,
+      });
+
+      if (!isDefined(relatedFlatEntity)) {
+        continue;
+      }
+
+      if (
+        !Object.prototype.hasOwnProperty.call(
+          relatedFlatEntity,
+          flatEntityForeignKeyAggregator,
+        )
+      ) {
+        throw new FlatEntityMapsException(
+          `Should never occur, invalid flat entity typing. flat ${metadataName} should contain ${flatEntityForeignKeyAggregator}`,
+          FlatEntityMapsExceptionCode.ENTITY_MALFORMED,
+        );
+      }
+
+      const updatedRelatedEntity = {
+        ...relatedFlatEntity,
+        [flatEntityForeignKeyAggregator]: (
+          relatedFlatEntity[
+            flatEntityForeignKeyAggregator
+          ] as unknown as string[]
+        ).filter((id) => id !== flatEntity.id),
+      };
+
+      replaceFlatEntityInFlatEntityMapsThroughMutationOrThrow({
+        flatEntity: updatedRelatedEntity,
+        flatEntityMapsToMutate: relatedFlatEntityMetadataMaps,
+      });
+    }
+  };