From 0adb27560623594b1c94a0dede779163209ad362 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Wed, 21 Oct 2026 03:16:56 -0400
Subject: [PATCH 1/9] fix(leaderboards): use a Set and a Map for rankings
 lookups

@IsEnum(fields, { each: true }) rebuilt the list of all 2,718 player leaderboard
fields for every value, and getLeaderboardField searched the metadata array for
each field. Validate against a Set with IsEnum's message, and look fields up in
a Map built once per class. A test checks that scanMetadata returns each Player
and Guild key once, since a Map keeps the last entry for a repeated key.
---
 apps/api/src/dtos/player-rankings.dto.ts      | 21 +++++++++++++++++--
 .../schemas/src/metadata/metadata-scanner.ts  | 12 +++++++++++
 .../schemas/src/util/leaderboard-scanner.ts   | 14 ++++++++++---
 3 files changed, 42 insertions(+), 5 deletions(-)

diff --git a/apps/api/src/dtos/player-rankings.dto.ts b/apps/api/src/dtos/player-rankings.dto.ts
index 8f29c9010..8bf984f2f 100644
--- a/apps/api/src/dtos/player-rankings.dto.ts
+++ b/apps/api/src/dtos/player-rankings.dto.ts
@@ -7,14 +7,31 @@
  */
 
 import { ApiProperty } from "@nestjs/swagger";
-import { IsEnum } from "class-validator";
+import { IS_ENUM, ValidateBy, buildMessage } from "class-validator";
 import { Player, getLeaderboardFields } from "@statsify/schemas";
 import { UuidDto } from "./uuid.dto.js";
 
 const fields = getLeaderboardFields(Player).map(([key]) => key);
+const fieldSet = new Set(fields);
+
+// @IsEnum(fields, { each: true }) rebuilt the list of every field for each value. This checks a
+// Set instead and keeps IsEnum's name and message, which lists no values for an array
+const IsLeaderboardField = ValidateBy(
+  {
+    name: IS_ENUM,
+    validator: {
+      validate: (value) => fieldSet.has(value),
+      defaultMessage: buildMessage(
+        (eachPrefix) => `${eachPrefix}$property must be one of the following values: `,
+        { each: true }
+      ),
+    },
+  },
+  { each: true }
+);
 
 export class PlayerRankingsDto extends UuidDto {
   @ApiProperty({ enum: fields, type: [String] })
-  @IsEnum(fields, { each: true })
+  @IsLeaderboardField
   public fields: string[];
 }
diff --git a/packages/schemas/src/metadata/metadata-scanner.ts b/packages/schemas/src/metadata/metadata-scanner.ts
index 5a7d3ef1c..abc642eed 100644
--- a/packages/schemas/src/metadata/metadata-scanner.ts
+++ b/packages/schemas/src/metadata/metadata-scanner.ts
@@ -343,5 +343,17 @@ if (import.meta.vitest) {
         resetEvery: undefined,
       });
     });
+
+    it("should return each key once for Player and Guild", async () => {
+      // getLeaderboardField keeps these in a Map, which would keep the last entry for a repeated key
+      const { Player } = await import("../player/index.js");
+      const { Guild } = await import("../guild/index.js");
+
+      for (const constructor of [Player, Guild]) {
+        const keys = scanMetadata(constructor).map(([key]) => key);
+        expect(keys.length).toBeGreaterThan(0);
+        expect(keys.filter((key, index) => keys.indexOf(key) !== index)).toEqual([]);
+      }
+    });
   });
 }
diff --git a/packages/schemas/src/util/leaderboard-scanner.ts b/packages/schemas/src/util/leaderboard-scanner.ts
index 4260ace0b..e4ed16ad1 100644
--- a/packages/schemas/src/util/leaderboard-scanner.ts
+++ b/packages/schemas/src/util/leaderboard-scanner.ts
@@ -7,6 +7,7 @@
  */
 
 import {
+  type FieldMetadata,
   type LeaderboardEnabledMetadata,
   type LeaderboardMetadata,
   scanMetadata,
@@ -14,6 +15,8 @@ import {
 import { parseAdditionalFields } from "./parse-fields.js";
 import type { Constructor } from "@statsify/util";
 
+const fieldMaps = new Map<Constructor, Map<string, FieldMetadata>>();
+
 export function getLeaderboardFields<T>(constructor: Constructor<T>) {
   const metadata = scanMetadata(constructor);
 
@@ -37,13 +40,18 @@ export function getLeaderboardField<T>(
   key: string,
   leaderboardMustBeEnabled = true,
 ): LeaderboardMetadata {
-  const metadata = scanMetadata(constructor);
+  let fields = fieldMaps.get(constructor);
+
+  if (!fields) {
+    fields = new Map(scanMetadata(constructor));
+    fieldMaps.set(constructor, fields);
+  }
 
-  const field = metadata.find(([k]) => k === key);
+  const field = fields.get(key);
 
   if (!field) throw new Error(`${key} is not a field for ${constructor.name}`);
 
-  const [, { store, leaderboard }] = field;
+  const { store, leaderboard } = field;
 
   if (!leaderboard.enabled && leaderboardMustBeEnabled)
     throw new Error(

From 197af533c50ae533bcc82c5446580ff0b794fd3c Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Wed, 21 Oct 2026 09:24:24 -0400
Subject: [PATCH 2/9] fix(api): name the unknown fields in rankings errors

A bad field in a player or guild rankings request got "each value in fields
must be one of the following values: " with nothing after it, since IsEnum
reads an array's indexes as enum keys. A valid field sent as a string instead
of an array passed validation, was ranked letter by letter and threw a 500.

- Name the values that aren't leaderboard fields, e.g.
  unknown leaderboard field: "stats.bedwars.foo"
- Answer anything but an array with a 400:
  fields must be an array of leaderboard fields
- Give guild rankings the same check
- Run apps/api's in-source tests, for the message test
---
 apps/api/src/dtos/guild-rankings.dto.ts       |  5 +-
 .../src/dtos/leaderboard-field.decorator.ts   | 60 +++++++++++++++++++
 apps/api/src/dtos/player-rankings.dto.ts      | 21 +------
 apps/api/tsconfig.json                        |  2 +-
 apps/api/vitest.config.ts                     | 11 ++++
 5 files changed, 77 insertions(+), 22 deletions(-)
 create mode 100644 apps/api/src/dtos/leaderboard-field.decorator.ts
 create mode 100644 apps/api/vitest.config.ts

diff --git a/apps/api/src/dtos/guild-rankings.dto.ts b/apps/api/src/dtos/guild-rankings.dto.ts
index bb3b8f798..0859127b8 100644
--- a/apps/api/src/dtos/guild-rankings.dto.ts
+++ b/apps/api/src/dtos/guild-rankings.dto.ts
@@ -8,13 +8,14 @@
 
 import { ApiProperty } from "@nestjs/swagger";
 import { Guild, getLeaderboardFields } from "@statsify/schemas";
-import { IsEnum, IsString, MaxLength, MinLength } from "class-validator";
+import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
+import { IsString, MaxLength, MinLength } from "class-validator";
 
 const fields = getLeaderboardFields(Guild).map(([key]) => key);
 
 export class GuildRankingDto {
   @ApiProperty({ enum: fields, type: [String] })
-  @IsEnum(fields, { each: true })
+  @IsLeaderboardField(fields)
   public fields: string[];
 
   @IsString()
diff --git a/apps/api/src/dtos/leaderboard-field.decorator.ts b/apps/api/src/dtos/leaderboard-field.decorator.ts
new file mode 100644
index 000000000..279e3bca7
--- /dev/null
+++ b/apps/api/src/dtos/leaderboard-field.decorator.ts
@@ -0,0 +1,60 @@
+/**
+ * Copyright (c) Statsify
+ *
+ * This source code is licensed under the GNU GPL v3 license found in the
+ * LICENSE file in the root directory of this source tree.
+ * https://github.com/Statsify/statsify/blob/main/LICENSE
+ */
+
+import { ValidateBy } from "class-validator";
+
+// Replaces @IsEnum(fields, { each: true }), which rebuilt the list of every field for each value and,
+// since it reads an array's indexes as enum keys, listed no values in its message. This checks a Set,
+// requires an array (a lone string passed validation and was ranked letter by letter) and names the
+// values that aren't fields, quoted so an empty string or a stray space still shows
+export const IsLeaderboardField = (fields: string[]) => {
+  const fieldSet = new Set(fields);
+
+  return ValidateBy({
+    name: "isLeaderboardField",
+    validator: {
+      validate: (value) => Array.isArray(value) && value.every((field) => fieldSet.has(field)),
+      defaultMessage: (args) => {
+        const value: unknown = args?.value;
+        if (!Array.isArray(value)) return `${args?.property} must be an array of leaderboard fields`;
+
+        const unknown = new Set(
+          value.filter((field) => !fieldSet.has(field)).map((field) => JSON.stringify(field))
+        );
+
+        return `unknown leaderboard field${unknown.size === 1 ? "" : "s"}: ${[...unknown].join(", ")}`;
+      },
+    },
+  });
+};
+
+if (import.meta.vitest) {
+  const { it, expect } = import.meta.vitest;
+  const { validate } = await import("class-validator");
+
+  class Dto {
+    @IsLeaderboardField(["wins", "kills"])
+    public fields: unknown;
+  }
+
+  const messages = async (fields: unknown) => {
+    const errors = await validate(Object.assign(new Dto(), { fields }));
+    return errors.flatMap((error) => Object.values(error.constraints ?? {}));
+  };
+
+  it("names the values that aren't leaderboard fields", async () => {
+    await expect(messages(["wins", "kills"])).resolves.toEqual([]);
+    await expect(messages(["wins", "nope"])).resolves.toEqual(['unknown leaderboard field: "nope"']);
+    await expect(messages(["nope", 5, "nope", ""])).resolves.toEqual([
+      'unknown leaderboard fields: "nope", 5, ""',
+    ]);
+    await expect(messages("wins")).resolves.toEqual([
+      "fields must be an array of leaderboard fields",
+    ]);
+  });
+}
diff --git a/apps/api/src/dtos/player-rankings.dto.ts b/apps/api/src/dtos/player-rankings.dto.ts
index 8bf984f2f..0414cfaf2 100644
--- a/apps/api/src/dtos/player-rankings.dto.ts
+++ b/apps/api/src/dtos/player-rankings.dto.ts
@@ -7,31 +7,14 @@
  */
 
 import { ApiProperty } from "@nestjs/swagger";
-import { IS_ENUM, ValidateBy, buildMessage } from "class-validator";
+import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
 import { Player, getLeaderboardFields } from "@statsify/schemas";
 import { UuidDto } from "./uuid.dto.js";
 
 const fields = getLeaderboardFields(Player).map(([key]) => key);
-const fieldSet = new Set(fields);
-
-// @IsEnum(fields, { each: true }) rebuilt the list of every field for each value. This checks a
-// Set instead and keeps IsEnum's name and message, which lists no values for an array
-const IsLeaderboardField = ValidateBy(
-  {
-    name: IS_ENUM,
-    validator: {
-      validate: (value) => fieldSet.has(value),
-      defaultMessage: buildMessage(
-        (eachPrefix) => `${eachPrefix}$property must be one of the following values: `,
-        { each: true }
-      ),
-    },
-  },
-  { each: true }
-);
 
 export class PlayerRankingsDto extends UuidDto {
   @ApiProperty({ enum: fields, type: [String] })
-  @IsLeaderboardField
+  @IsLeaderboardField(fields)
   public fields: string[];
 }
diff --git a/apps/api/tsconfig.json b/apps/api/tsconfig.json
index dd3fcc5f4..4331b10e2 100644
--- a/apps/api/tsconfig.json
+++ b/apps/api/tsconfig.json
@@ -1,4 +1,4 @@
 {
   "extends": "../../tsconfig.base.json",
-  "include": ["src"]
+  "include": ["src", "vitest.config.ts"]
 }
\ No newline at end of file
diff --git a/apps/api/vitest.config.ts b/apps/api/vitest.config.ts
new file mode 100644
index 000000000..2f7603e59
--- /dev/null
+++ b/apps/api/vitest.config.ts
@@ -0,0 +1,11 @@
+/**
+ * Copyright (c) Statsify
+ *
+ * This source code is licensed under the GNU GPL v3 license found in the
+ * LICENSE file in the root directory of this source tree.
+ * https://github.com/Statsify/statsify/blob/main/LICENSE
+ */
+
+import { config } from "../../vitest.shared.js";
+
+export default await config();

From efd6d74ce35da20d337299a4edf78fc50de133a4 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 22 Oct 2026 00:23:22 -0400
Subject: [PATCH 3/9] test(schemas): drop the one-off scanMetadata unique-keys
 test

---
 packages/schemas/src/metadata/metadata-scanner.ts | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/packages/schemas/src/metadata/metadata-scanner.ts b/packages/schemas/src/metadata/metadata-scanner.ts
index abc642eed..5a7d3ef1c 100644
--- a/packages/schemas/src/metadata/metadata-scanner.ts
+++ b/packages/schemas/src/metadata/metadata-scanner.ts
@@ -343,17 +343,5 @@ if (import.meta.vitest) {
         resetEvery: undefined,
       });
     });
-
-    it("should return each key once for Player and Guild", async () => {
-      // getLeaderboardField keeps these in a Map, which would keep the last entry for a repeated key
-      const { Player } = await import("../player/index.js");
-      const { Guild } = await import("../guild/index.js");
-
-      for (const constructor of [Player, Guild]) {
-        const keys = scanMetadata(constructor).map(([key]) => key);
-        expect(keys.length).toBeGreaterThan(0);
-        expect(keys.filter((key, index) => keys.indexOf(key) !== index)).toEqual([]);
-      }
-    });
   });
 }

From 633a5c9d794e5ec4c1844af58fe0cfbcc38d6338 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 22 Oct 2026 00:29:26 -0400
Subject: [PATCH 4/9] refactor(api): trim the IsLeaderboardField comment and
 rename its unknown set

---
 apps/api/src/dtos/leaderboard-field.decorator.ts | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/apps/api/src/dtos/leaderboard-field.decorator.ts b/apps/api/src/dtos/leaderboard-field.decorator.ts
index 279e3bca7..03154139d 100644
--- a/apps/api/src/dtos/leaderboard-field.decorator.ts
+++ b/apps/api/src/dtos/leaderboard-field.decorator.ts
@@ -8,10 +8,6 @@
 
 import { ValidateBy } from "class-validator";
 
-// Replaces @IsEnum(fields, { each: true }), which rebuilt the list of every field for each value and,
-// since it reads an array's indexes as enum keys, listed no values in its message. This checks a Set,
-// requires an array (a lone string passed validation and was ranked letter by letter) and names the
-// values that aren't fields, quoted so an empty string or a stray space still shows
 export const IsLeaderboardField = (fields: string[]) => {
   const fieldSet = new Set(fields);
 
@@ -23,11 +19,12 @@ export const IsLeaderboardField = (fields: string[]) => {
         const value: unknown = args?.value;
         if (!Array.isArray(value)) return `${args?.property} must be an array of leaderboard fields`;
 
-        const unknown = new Set(
+        // Quoted so an empty string or a stray space still shows
+        const invalid = new Set(
           value.filter((field) => !fieldSet.has(field)).map((field) => JSON.stringify(field))
         );
 
-        return `unknown leaderboard field${unknown.size === 1 ? "" : "s"}: ${[...unknown].join(", ")}`;
+        return `unknown leaderboard field${invalid.size === 1 ? "" : "s"}: ${[...invalid].join(", ")}`;
       },
     },
   });

From 911d7296a07d949c5e0125798193aec277cee361 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 22 Oct 2026 00:35:34 -0400
Subject: [PATCH 5/9] test(api): drop the one-off rankings error message test

---
 .../src/dtos/leaderboard-field.decorator.ts   | 26 -------------------
 apps/api/tsconfig.json                        |  2 +-
 apps/api/vitest.config.ts                     | 11 --------
 3 files changed, 1 insertion(+), 38 deletions(-)
 delete mode 100644 apps/api/vitest.config.ts

diff --git a/apps/api/src/dtos/leaderboard-field.decorator.ts b/apps/api/src/dtos/leaderboard-field.decorator.ts
index 03154139d..1ab1e9d9f 100644
--- a/apps/api/src/dtos/leaderboard-field.decorator.ts
+++ b/apps/api/src/dtos/leaderboard-field.decorator.ts
@@ -29,29 +29,3 @@ export const IsLeaderboardField = (fields: string[]) => {
     },
   });
 };
-
-if (import.meta.vitest) {
-  const { it, expect } = import.meta.vitest;
-  const { validate } = await import("class-validator");
-
-  class Dto {
-    @IsLeaderboardField(["wins", "kills"])
-    public fields: unknown;
-  }
-
-  const messages = async (fields: unknown) => {
-    const errors = await validate(Object.assign(new Dto(), { fields }));
-    return errors.flatMap((error) => Object.values(error.constraints ?? {}));
-  };
-
-  it("names the values that aren't leaderboard fields", async () => {
-    await expect(messages(["wins", "kills"])).resolves.toEqual([]);
-    await expect(messages(["wins", "nope"])).resolves.toEqual(['unknown leaderboard field: "nope"']);
-    await expect(messages(["nope", 5, "nope", ""])).resolves.toEqual([
-      'unknown leaderboard fields: "nope", 5, ""',
-    ]);
-    await expect(messages("wins")).resolves.toEqual([
-      "fields must be an array of leaderboard fields",
-    ]);
-  });
-}
diff --git a/apps/api/tsconfig.json b/apps/api/tsconfig.json
index 4331b10e2..dd3fcc5f4 100644
--- a/apps/api/tsconfig.json
+++ b/apps/api/tsconfig.json
@@ -1,4 +1,4 @@
 {
   "extends": "../../tsconfig.base.json",
-  "include": ["src", "vitest.config.ts"]
+  "include": ["src"]
 }
\ No newline at end of file
diff --git a/apps/api/vitest.config.ts b/apps/api/vitest.config.ts
deleted file mode 100644
index 2f7603e59..000000000
--- a/apps/api/vitest.config.ts
+++ /dev/null
@@ -1,11 +0,0 @@
-/**
- * Copyright (c) Statsify
- *
- * This source code is licensed under the GNU GPL v3 license found in the
- * LICENSE file in the root directory of this source tree.
- * https://github.com/Statsify/statsify/blob/main/LICENSE
- */
-
-import { config } from "../../vitest.shared.js";
-
-export default await config();

From 49f2e7a6740d7330db861003d562fb0d9e10c3c4 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:55:04 -0400
Subject: [PATCH 6/9] refactor(schemas): leave the getLeaderboardField Map to
 #1008

---
 packages/schemas/src/util/leaderboard-scanner.ts | 14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/packages/schemas/src/util/leaderboard-scanner.ts b/packages/schemas/src/util/leaderboard-scanner.ts
index e4ed16ad1..4260ace0b 100644
--- a/packages/schemas/src/util/leaderboard-scanner.ts
+++ b/packages/schemas/src/util/leaderboard-scanner.ts
@@ -7,7 +7,6 @@
  */
 
 import {
-  type FieldMetadata,
   type LeaderboardEnabledMetadata,
   type LeaderboardMetadata,
   scanMetadata,
@@ -15,8 +14,6 @@ import {
 import { parseAdditionalFields } from "./parse-fields.js";
 import type { Constructor } from "@statsify/util";
 
-const fieldMaps = new Map<Constructor, Map<string, FieldMetadata>>();
-
 export function getLeaderboardFields<T>(constructor: Constructor<T>) {
   const metadata = scanMetadata(constructor);
 
@@ -40,18 +37,13 @@ export function getLeaderboardField<T>(
   key: string,
   leaderboardMustBeEnabled = true,
 ): LeaderboardMetadata {
-  let fields = fieldMaps.get(constructor);
-
-  if (!fields) {
-    fields = new Map(scanMetadata(constructor));
-    fieldMaps.set(constructor, fields);
-  }
+  const metadata = scanMetadata(constructor);
 
-  const field = fields.get(key);
+  const field = metadata.find(([k]) => k === key);
 
   if (!field) throw new Error(`${key} is not a field for ${constructor.name}`);
 
-  const { store, leaderboard } = field;
+  const [, { store, leaderboard }] = field;
 
   if (!leaderboard.enabled && leaderboardMustBeEnabled)
     throw new Error(

From 649e8dc7ab0ac3b41345519a574778ff39381fad Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 5 Nov 2026 00:31:25 -0500
Subject: [PATCH 7/9] refactor(api): drop the quoting comment in
 IsLeaderboardField

---
 apps/api/src/dtos/leaderboard-field.decorator.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/apps/api/src/dtos/leaderboard-field.decorator.ts b/apps/api/src/dtos/leaderboard-field.decorator.ts
index 1ab1e9d9f..ceed19a78 100644
--- a/apps/api/src/dtos/leaderboard-field.decorator.ts
+++ b/apps/api/src/dtos/leaderboard-field.decorator.ts
@@ -19,7 +19,6 @@ export const IsLeaderboardField = (fields: string[]) => {
         const value: unknown = args?.value;
         if (!Array.isArray(value)) return `${args?.property} must be an array of leaderboard fields`;
 
-        // Quoted so an empty string or a stray space still shows
         const invalid = new Set(
           value.filter((field) => !fieldSet.has(field)).map((field) => JSON.stringify(field))
         );

From a9fccf6e74a2a5e3735dd251aade288eb5d562d8 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 5 Nov 2026 00:42:14 -0500
Subject: [PATCH 8/9] refactor(api): validate one leaderboard field per
 IsLeaderboardField check

---
 apps/api/src/dtos/guild-rankings.dto.ts       |  5 +--
 .../src/dtos/leaderboard-field.decorator.ts   | 32 +++++++++++--------
 apps/api/src/dtos/player-rankings.dto.ts      |  4 ++-
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/apps/api/src/dtos/guild-rankings.dto.ts b/apps/api/src/dtos/guild-rankings.dto.ts
index 0859127b8..60fc81dc1 100644
--- a/apps/api/src/dtos/guild-rankings.dto.ts
+++ b/apps/api/src/dtos/guild-rankings.dto.ts
@@ -8,14 +8,15 @@
 
 import { ApiProperty } from "@nestjs/swagger";
 import { Guild, getLeaderboardFields } from "@statsify/schemas";
+import { IsArray, IsString, MaxLength, MinLength } from "class-validator";
 import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
-import { IsString, MaxLength, MinLength } from "class-validator";
 
 const fields = getLeaderboardFields(Guild).map(([key]) => key);
 
 export class GuildRankingDto {
   @ApiProperty({ enum: fields, type: [String] })
-  @IsLeaderboardField(fields)
+  @IsArray()
+  @IsLeaderboardField(fields, { each: true })
   public fields: string[];
 
   @IsString()
diff --git a/apps/api/src/dtos/leaderboard-field.decorator.ts b/apps/api/src/dtos/leaderboard-field.decorator.ts
index ceed19a78..db6428d8a 100644
--- a/apps/api/src/dtos/leaderboard-field.decorator.ts
+++ b/apps/api/src/dtos/leaderboard-field.decorator.ts
@@ -6,25 +6,29 @@
  * https://github.com/Statsify/statsify/blob/main/LICENSE
  */
 
-import { ValidateBy } from "class-validator";
+import { ValidateBy, type ValidationOptions } from "class-validator";
 
-export const IsLeaderboardField = (fields: string[]) => {
+export const IsLeaderboardField = (fields: string[], options?: ValidationOptions) => {
   const fieldSet = new Set(fields);
 
-  return ValidateBy({
-    name: "isLeaderboardField",
-    validator: {
-      validate: (value) => Array.isArray(value) && value.every((field) => fieldSet.has(field)),
-      defaultMessage: (args) => {
-        const value: unknown = args?.value;
-        if (!Array.isArray(value)) return `${args?.property} must be an array of leaderboard fields`;
+  return ValidateBy(
+    {
+      name: "isLeaderboardField",
+      validator: {
+        validate: (value) => fieldSet.has(value),
+        defaultMessage: (args) => {
+          const value = args?.value;
+          if (value === undefined) return `${args?.property} is required`;
 
-        const invalid = new Set(
-          value.filter((field) => !fieldSet.has(field)).map((field) => JSON.stringify(field))
-        );
+          const values = options?.each && Array.isArray(value) ? value : [value];
+          const invalid = new Set(
+            values.filter((field) => !fieldSet.has(field)).map((field) => JSON.stringify(field))
+          );
 
-        return `unknown leaderboard field${invalid.size === 1 ? "" : "s"}: ${[...invalid].join(", ")}`;
+          return `unknown leaderboard field${invalid.size === 1 ? "" : "s"}: ${[...invalid].join(", ")}`;
+        },
       },
     },
-  });
+    options
+  );
 };
diff --git a/apps/api/src/dtos/player-rankings.dto.ts b/apps/api/src/dtos/player-rankings.dto.ts
index 0414cfaf2..f627bcc00 100644
--- a/apps/api/src/dtos/player-rankings.dto.ts
+++ b/apps/api/src/dtos/player-rankings.dto.ts
@@ -7,6 +7,7 @@
  */
 
 import { ApiProperty } from "@nestjs/swagger";
+import { IsArray } from "class-validator";
 import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
 import { Player, getLeaderboardFields } from "@statsify/schemas";
 import { UuidDto } from "./uuid.dto.js";
@@ -15,6 +16,7 @@ const fields = getLeaderboardFields(Player).map(([key]) => key);
 
 export class PlayerRankingsDto extends UuidDto {
   @ApiProperty({ enum: fields, type: [String] })
-  @IsLeaderboardField(fields)
+  @IsArray()
+  @IsLeaderboardField(fields, { each: true })
   public fields: string[];
 }

From 4687a554b64d2c346b9638d12b4ef709da337ae4 Mon Sep 17 00:00:00 2001
From: Cody <36463298+ugcodrr@users.noreply.github.com>
Date: Thu, 5 Nov 2026 00:42:14 -0500
Subject: [PATCH 9/9] fix(api): name the unknown field in leaderboard errors

---
 apps/api/src/dtos/guild-leaderboard.dto.ts  | 4 ++--
 apps/api/src/dtos/player-leaderboard.dto.ts | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/apps/api/src/dtos/guild-leaderboard.dto.ts b/apps/api/src/dtos/guild-leaderboard.dto.ts
index 483977c3a..6b98ee790 100644
--- a/apps/api/src/dtos/guild-leaderboard.dto.ts
+++ b/apps/api/src/dtos/guild-leaderboard.dto.ts
@@ -9,7 +9,6 @@
 import { ApiProperty } from "@nestjs/swagger";
 import { Guild, getLeaderboardFields } from "@statsify/schemas";
 import {
-  IsEnum,
   IsInt,
   IsOptional,
   IsString,
@@ -17,12 +16,13 @@ import {
   Min,
   MinLength,
 } from "class-validator";
+import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
 import { Transform } from "class-transformer";
 
 const fields = getLeaderboardFields(Guild).map(([key]) => key);
 
 export class GuildLeaderboardDto {
-  @IsEnum(fields)
+  @IsLeaderboardField(fields)
   @ApiProperty({ enum: fields })
   public field: string;
 
diff --git a/apps/api/src/dtos/player-leaderboard.dto.ts b/apps/api/src/dtos/player-leaderboard.dto.ts
index 0e39b70ed..8ef1d3e35 100644
--- a/apps/api/src/dtos/player-leaderboard.dto.ts
+++ b/apps/api/src/dtos/player-leaderboard.dto.ts
@@ -7,7 +7,8 @@
  */
 
 import { ApiProperty, PartialType } from "@nestjs/swagger";
-import { IsEnum, IsInt, IsOptional, Min } from "class-validator";
+import { IsInt, IsOptional, Min } from "class-validator";
+import { IsLeaderboardField } from "./leaderboard-field.decorator.js";
 import { Player, getLeaderboardFields } from "@statsify/schemas";
 import { PlayerDto } from "./player.dto.js";
 import { Transform } from "class-transformer";
@@ -15,7 +16,7 @@ import { Transform } from "class-transformer";
 const fields = getLeaderboardFields(Player).map(([key]) => key);
 
 export class PlayerLeaderboardDto extends PartialType(PlayerDto) {
-  @IsEnum(fields)
+  @IsLeaderboardField(fields)
   @ApiProperty({ enum: fields })
   public field: string;