From d93390dea78c17fd2eb54694b2f0c803a330d2b3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fredrik=20Adel=C3=B6w?= <freben@gmail.com>
Date: Thu, 5 Dec 2024 22:06:28 +0100
Subject: [PATCH] simplify the generated filters when parsing a query
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Signed-off-by: Fredrik Adelöw <freben@gmail.com>
---
 .changeset/small-boxes-enjoy.md                    |  5 +++++
 .../src/service/createRouter.test.ts               | 14 ++++----------
 .../request/parseEntityFilterParams.test.ts        | 10 ++++------
 .../src/service/request/parseEntityFilterParams.ts |  9 +++++++--
 4 files changed, 20 insertions(+), 18 deletions(-)
 create mode 100644 .changeset/small-boxes-enjoy.md

diff --git a/.changeset/small-boxes-enjoy.md b/.changeset/small-boxes-enjoy.md
new file mode 100644
index 0000000000..819e247d49
--- /dev/null
+++ b/.changeset/small-boxes-enjoy.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-catalog-backend': patch
+---
+
+When parsing filters, do not make redundant `anyOf` and `allOf` nodes when there's only a single entry within them
diff --git a/plugins/catalog-backend/src/service/createRouter.test.ts b/plugins/catalog-backend/src/service/createRouter.test.ts
index 6654187526..7cba2edea9 100644
--- a/plugins/catalog-backend/src/service/createRouter.test.ts
+++ b/plugins/catalog-backend/src/service/createRouter.test.ts
@@ -166,7 +166,7 @@ describe('createRouter readonly disabled', () => {
                 { key: 'b', values: ['3'] },
               ],
             },
-            { allOf: [{ key: 'c', values: ['4'] }] },
+            { key: 'c', values: ['4'] },
           ],
         },
         credentials: mockCredentials.user(),
@@ -218,7 +218,7 @@ describe('createRouter readonly disabled', () => {
                 { key: 'b', values: ['3'] },
               ],
             },
-            { allOf: [{ key: 'c', values: ['4'] }] },
+            { key: 'c', values: ['4'] },
           ],
         },
         orderFields: [
@@ -258,7 +258,7 @@ describe('createRouter readonly disabled', () => {
                 { key: 'b', values: ['3'] },
               ],
             },
-            { allOf: [{ key: 'c', values: ['4'] }] },
+            { key: 'c', values: ['4'] },
           ],
         },
         orderFields: [
@@ -554,13 +554,7 @@ describe('createRouter readonly disabled', () => {
         entityRefs: [entityRef],
         fields: expect.any(Function),
         credentials: mockCredentials.user(),
-        filter: {
-          anyOf: [
-            {
-              allOf: [{ key: 'kind', values: ['Component'] }],
-            },
-          ],
-        },
+        filter: { key: 'kind', values: ['Component'] },
       });
       expect(response.status).toEqual(200);
       expect(response.body).toEqual({ items: [entity] });
diff --git a/plugins/catalog-backend/src/service/request/parseEntityFilterParams.test.ts b/plugins/catalog-backend/src/service/request/parseEntityFilterParams.test.ts
index f9fc596cb9..85e0d9caa1 100644
--- a/plugins/catalog-backend/src/service/request/parseEntityFilterParams.test.ts
+++ b/plugins/catalog-backend/src/service/request/parseEntityFilterParams.test.ts
@@ -27,9 +27,7 @@ describe('parseEntityFilterParams', () => {
 
   it('supports single-string format', () => {
     const result = parseEntityFilterParams({ filter: 'a=1' })!;
-    expect(result).toEqual({
-      anyOf: [{ allOf: [{ key: 'a', values: ['1'] }] }],
-    });
+    expect(result).toEqual({ key: 'a', values: ['1'] });
   });
 
   it('supports array-of-strings format', () => {
@@ -38,8 +36,8 @@ describe('parseEntityFilterParams', () => {
     });
     expect(result).toEqual({
       anyOf: [
-        { allOf: [{ key: 'a', values: ['1'] }] },
-        { allOf: [{ key: 'b', values: ['2'] }] },
+        { key: 'a', values: ['1'] },
+        { key: 'b', values: ['2'] },
       ],
     });
   });
@@ -50,7 +48,7 @@ describe('parseEntityFilterParams', () => {
     });
     expect(result).toEqual({
       anyOf: [
-        { allOf: [{ key: 'a', values: ['1'] }] },
+        { key: 'a', values: ['1'] },
         {
           allOf: [
             { key: 'b', values: ['2', '3'] },
diff --git a/plugins/catalog-backend/src/service/request/parseEntityFilterParams.ts b/plugins/catalog-backend/src/service/request/parseEntityFilterParams.ts
index 8666712f80..aabb24ff3f 100644
--- a/plugins/catalog-backend/src/service/request/parseEntityFilterParams.ts
+++ b/plugins/catalog-backend/src/service/request/parseEntityFilterParams.ts
@@ -36,12 +36,17 @@ export function parseEntityFilterParams(
 
   // Outer array: "any of the inner ones"
   // Inner arrays: "all of these must match"
-  const filters = filterStrings.map(parseEntityFilterString).filter(Boolean);
+  const filters = filterStrings
+    .map(parseEntityFilterString)
+    .filter((r): r is EntitiesSearchFilter[] => Boolean(r));
   if (!filters.length) {
     return undefined;
   }
 
-  return { anyOf: filters.map(f => ({ allOf: f! })) };
+  const outer = filters.map(inner =>
+    inner.length === 1 ? inner[0] : { allOf: inner },
+  );
+  return outer.length === 1 ? outer[0] : { anyOf: outer };
 }
 
 /**