From a0a58e7fd20dff54d210c968f4d5defd67441bdd Mon Sep 17 00:00:00 2001
From: Elliot DeNolf <denolfe@users.noreply.github.com>
Date: Wed, 7 Feb 2024 14:18:13 -0500
Subject: [PATCH] fix: query relationships by explicit id field (#5022)

---
 .../src/queries/getTableColumnFromPath.ts     |  2 +-
 .../payload/src/database/getLocalizedPaths.ts | 11 +++
 test/relationships/int.spec.ts                | 72 ++++++++++++++++++-
 3 files changed, 82 insertions(+), 3 deletions(-)

diff --git a/packages/db-postgres/src/queries/getTableColumnFromPath.ts b/packages/db-postgres/src/queries/getTableColumnFromPath.ts
index f19349151f..2f01c0d906 100644
--- a/packages/db-postgres/src/queries/getTableColumnFromPath.ts
+++ b/packages/db-postgres/src/queries/getTableColumnFromPath.ts
@@ -349,7 +349,7 @@ export const getTableColumnFromPath = ({
             table: newAliasTable,
           })
 
-          if (newCollectionPath === '') {
+          if (newCollectionPath === '' || newCollectionPath === 'id') {
             return {
               columnName: `${field.relationTo}ID`,
               constraints,
diff --git a/packages/payload/src/database/getLocalizedPaths.ts b/packages/payload/src/database/getLocalizedPaths.ts
index 56d660a5bb..d3c51ae8b1 100644
--- a/packages/payload/src/database/getLocalizedPaths.ts
+++ b/packages/payload/src/database/getLocalizedPaths.ts
@@ -62,6 +62,17 @@ export async function getLocalizedPaths({
         return paths
       }
 
+      if (!matchedField && currentPath === 'id' && i === pathSegments.length - 1) {
+        lastIncompletePath.path = currentPath
+        const idField: Field = {
+          name: 'id',
+          type: payload.db.defaultIDType as 'text',
+        }
+        lastIncompletePath.field = idField
+        lastIncompletePath.complete = true
+        return paths
+      }
+
       if (matchedField) {
         if ('hidden' in matchedField && matchedField.hidden && !overrideAccess) {
           lastIncompletePath.invalid = true
diff --git a/test/relationships/int.spec.ts b/test/relationships/int.spec.ts
index e04640c9f9..40fd912cc5 100644
--- a/test/relationships/int.spec.ts
+++ b/test/relationships/int.spec.ts
@@ -273,6 +273,74 @@ describe('Relationships', () => {
         expect(query.totalDocs).toEqual(2)
       })
 
+      // https://github.com/payloadcms/payload/issues/4240
+      it('should allow querying by relationship id field', async () => {
+        /**
+         * This test shows something which breaks on postgres but not on mongodb.
+         */
+        const someDirector = await payload.create({
+          collection: 'directors',
+          data: {
+            name: 'Quentin Tarantino',
+          },
+        })
+
+        await payload.create({
+          collection: 'movies',
+          data: {
+            name: 'Pulp Fiction',
+          },
+        })
+
+        await payload.create({
+          collection: 'movies',
+          data: {
+            name: 'Pulp Fiction',
+          },
+        })
+
+        await payload.create({
+          collection: 'movies',
+          data: {
+            name: 'Harry Potter',
+          },
+        })
+
+        await payload.create({
+          collection: 'movies',
+          data: {
+            name: 'Lord of the Rings is boring',
+            director: someDirector.id,
+          },
+        })
+
+        // This causes the following error:
+        // "Your "id" field references a column "directors"."id", but the table "directors" is not part of the query! Did you forget to join it?"
+        // This only happens on postgres, not on mongodb
+        const query = await payload.find({
+          collection: 'movies',
+          depth: 5,
+          limit: 1,
+          where: {
+            or: [
+              {
+                name: {
+                  equals: 'Pulp Fiction',
+                },
+              },
+              {
+                'director.id': {
+                  equals: someDirector.id,
+                },
+              },
+            ],
+          },
+        })
+
+        expect(query.totalDocs).toEqual(3)
+        expect(query.docs).toHaveLength(1) // Due to limit: 1
+      })
+
       describe('Custom ID', () => {
         it('should query a custom id relation', async () => {
           const { doc } = await client.findByID<Post>({ id: post.id })
@@ -288,7 +356,7 @@ describe('Relationships', () => {
           await expect(async () =>
             createPost({
               // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-              // @ts-ignore Sending bad data to test error handling
+              // @ts-expect-error Sending bad data to test error handling
               customIdRelation: 1234,
             }),
           ).rejects.toThrow('The following field is invalid: customIdRelation')
@@ -298,7 +366,7 @@ describe('Relationships', () => {
           await expect(async () =>
             createPost({
               // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-              // @ts-ignore Sending bad data to test error handling
+              // @ts-expect-error Sending bad data to test error handling
               customIdNumberRelation: 'bad-input',
             }),
           ).rejects.toThrow('The following field is invalid: customIdNumberRelation')