filter for relation existence

.changeset/fast-geese-mate.md

@@ -0,0 +1,7 @@
+---
+"@graphprotocol/hypergraph": patch
+"@graphprotocol/hypergraph-react": patch
+---
+
+extend filter capability to check for existing relation e.g. `filter: { cover: { exists: true } }`
+

apps/events/src/routes/podcasts.lazy.tsx

@@ -1,6 +1,6 @@
 import { useEntities } from '@graphprotocol/hypergraph-react';
 import { createLazyFileRoute } from '@tanstack/react-router';
-import { Podcast } from '@/schema';
+import { Podcast, Topic } from '@/schema';
 
 export const Route = createLazyFileRoute('/podcasts')({
   component: RouteComponent,
@@ -53,6 +53,23 @@ function RouteComponent() {
     orderBy: { property: 'dateFounded', direction: 'asc' },
     backlinksTotalCountsTypeId1: '972d201a-d780-4568-9e01-543f67b26bee',
   });
+
+  const { data: topics } = useEntities(Topic, {
+    mode: 'public',
+    first: 10,
+    space: space,
+    filter: {
+      cover: {
+        exists: true,
+      },
+    },
+    include: {
+      cover: {},
+    },
+  });
+
+  console.log({ topics });
+
   console.log({ data, isLoading, isError });
   return (
     <>

packages/hypergraph/src/entity/find-many-public.ts

@@ -127,8 +127,6 @@ export const parseResult = <S extends Schema.Schema.AnyNoContext>(
       ...Utils.convertRelations(queryEntity, ast, relationInfoLevel1),
     };
 
-    console.log('rawEntity', rawEntity);
-
     const decodeResult = decode({
       ...rawEntity,
       __deleted: false,

packages/hypergraph/src/entity/types.ts

@@ -64,23 +64,34 @@ export type CrossFieldFilter<T> = {
   not?: CrossFieldFilter<T>;
 };
 
-export type EntityFieldFilter<T> = {
-  is?: T;
-} & (T extends boolean
+type RelationExistsFilter<T> = [T] extends [readonly unknown[] | undefined]
   ? {
-      is?: boolean;
+      exists?: boolean;
     }
-  : T extends number
+  : Record<never, never>;
+
+type ScalarFieldFilter<T> = [T] extends [readonly unknown[] | undefined]
+  ? Record<never, never>
+  : T extends boolean
     ? {
-        greaterThan?: number;
-        lessThan?: number;
+        is?: boolean;
       }
-    : T extends string
+    : T extends number
       ? {
-          startsWith?: string;
-          endsWith?: string;
-          contains?: string;
+          greaterThan?: number;
+          lessThan?: number;
         }
-      : Record<string, never>);
+      : T extends string
+        ? {
+            startsWith?: string;
+            endsWith?: string;
+            contains?: string;
+          }
+        : Record<string, never>;
+
+export type EntityFieldFilter<T> = {
+  is?: T;
+} & RelationExistsFilter<T> &
+  ScalarFieldFilter<T>;
 
 export type EntityFilter<T> = CrossFieldFilter<T>;

packages/hypergraph/src/utils/translate-filter-to-graphql.ts

@@ -31,6 +31,13 @@ type GraphqlFilterEntry =
   | {
       and: GraphqlFilterEntry[];
     }
+  | {
+      relations: {
+        some: {
+          typeId: { is: string };
+        };
+      };
+    }
   | { [k: string]: never };
 
 /**
@@ -47,6 +54,14 @@ export function translateFilterToGraphql<S extends Schema.Schema.AnyNoContext>(
 
   const graphqlFilter: GraphqlFilterEntry[] = [];
 
+  const buildRelationExistsFilter = (propertyId: string): GraphqlFilterEntry => ({
+    relations: {
+      some: {
+        typeId: { is: propertyId },
+      },
+    },
+  });
+
   for (const [fieldName, fieldFilter] of Object.entries(filter)) {
     if (fieldName === 'or') {
       graphqlFilter.push({
@@ -77,6 +92,23 @@ export function translateFilterToGraphql<S extends Schema.Schema.AnyNoContext>(
 
     if (!Option.isSome(propertyId) || !Option.isSome(propertyType)) continue;
 
+    if (propertyType.value === 'relation') {
+      const relationFilter = fieldFilter as { exists?: boolean };
+
+      if (relationFilter.exists === true) {
+        graphqlFilter.push(buildRelationExistsFilter(propertyId.value));
+        continue;
+      }
+
+      if (relationFilter.exists === false) {
+        const existsFilter = buildRelationExistsFilter(propertyId.value);
+        graphqlFilter.push({
+          not: existsFilter,
+        });
+        continue;
+      }
+    }
+
     if (
       propertyType.value === 'string' &&
       (fieldFilter.is || fieldFilter.startsWith || fieldFilter.endsWith || fieldFilter.contains)

packages/hypergraph/test/utils/translate-filter-to-graphql.test.ts

@@ -4,18 +4,32 @@ import type * as Schema from 'effect/Schema';
 import { describe, expect, it } from 'vitest';
 import { translateFilterToGraphql } from '../../src/utils/translate-filter-to-graphql.js';
 
+export const User = Entity.Schema(
+  {
+    username: Type.String,
+  },
+  {
+    types: [Id('f6fa5a6a-7dbf-4c31-aba5-7b4cd0a9b2de')],
+    properties: {
+      username: Id('f0dfb5c0-3c90-4d30-98a3-6a139c8b5943'),
+    },
+  },
+);
+
 export const Todo = Entity.Schema(
   {
     name: Type.String,
     completed: Type.Boolean,
     priority: Type.Number,
+    assignees: Type.Relation(User),
   },
   {
     types: [Id('a288444f-06a3-4037-9ace-66fe325864d0')],
     properties: {
       name: Id('a126ca53-0c8e-48d5-b888-82c734c38935'),
       completed: Id('d2d64cd3-a337-4784-9e30-25bea0349471'),
       priority: Id('ee920534-42ce-4113-a63b-8f3c889dd772'),
+      assignees: Id('f399677c-2bf9-40c3-9622-815be7b83344'),
     },
   },
 );
@@ -147,6 +161,44 @@ describe('translateFilterToGraphql number filters', () => {
   });
 });
 
+describe('translateFilterToGraphql relation filters', () => {
+  it('should translate relation `exists` filter correctly', () => {
+    const filter: TodoFilter = {
+      // @ts-expect-error - this is a test
+      assignees: { exists: true },
+    };
+
+    const result = translateFilterToGraphql(filter, Todo);
+
+    expect(result).toEqual({
+      relations: {
+        some: {
+          typeId: { is: 'f399677c-2bf9-40c3-9622-815be7b83344' },
+        },
+      },
+    });
+  });
+
+  it('should translate relation `exists: false` filter correctly', () => {
+    const filter: TodoFilter = {
+      // @ts-expect-error - this is a test
+      assignees: { exists: false },
+    };
+
+    const result = translateFilterToGraphql(filter, Todo);
+
+    expect(result).toEqual({
+      not: {
+        relations: {
+          some: {
+            typeId: { is: 'f399677c-2bf9-40c3-9622-815be7b83344' },
+          },
+        },
+      },
+    });
+  });
+});
+
 describe('translateFilterToGraphql multiple filters', () => {
   it('should translate multiple filters correctly', () => {
     const filter: TodoFilter = {