feat(supabase): export DatabaseWithoutInternals utility type (#1935)

Co-authored-by: Katerina Skroumpelou <[email protected]>

Author: 7ttp

packages/core/supabase-js/src/index.ts

@@ -19,7 +19,13 @@ export {
 } from '@supabase/functions-js'
 export * from '@supabase/realtime-js'
 export { default as SupabaseClient } from './SupabaseClient'
-export type { SupabaseClientOptions, QueryResult, QueryData, QueryError } from './lib/types'
+export type {
+  SupabaseClientOptions,
+  QueryResult,
+  QueryData,
+  QueryError,
+  DatabaseWithoutInternals,
+} from './lib/types'
 
 /**
  * Creates a new Supabase Client.

packages/core/supabase-js/src/lib/types.ts

@@ -135,3 +135,17 @@ export type SupabaseClientOptions<SchemaName> = {
 export type QueryResult<T> = T extends PromiseLike<infer U> ? U : never
 export type QueryData<T> = T extends PromiseLike<{ data: infer U }> ? Exclude<U, null> : never
 export type QueryError = PostgrestError
+
+/** @internal Key used for Supabase internal metadata in Database types. */
+type InternalSupabaseKey = '__InternalSupabase'
+
+/**
+ * Strips internal Supabase metadata from Database types.
+ * Useful for libraries defining generic constraints on Database types.
+ *
+ * @example
+ * ```typescript
+ * type CleanDB = DatabaseWithoutInternals<Database>
+ * ```
+ */
+export type DatabaseWithoutInternals<DB> = Omit<DB, InternalSupabaseKey>

packages/core/supabase-js/test/types/index.test-d.ts

@@ -1,5 +1,10 @@
 import { expectError, expectType } from 'tsd'
-import { PostgrestSingleResponse, SupabaseClient, createClient } from '../../src/index'
+import {
+  PostgrestSingleResponse,
+  SupabaseClient,
+  createClient,
+  DatabaseWithoutInternals,
+} from '../../src/index'
 import { Database, Json } from '../types'
 
 const URL = 'http://localhost:3000'
@@ -265,3 +270,42 @@ const supabase = createClient<Database>(URL, KEY)
   // @ts-expect-error should raise error if providing table name not in the schema
   pg13CustomSchemaClient.from('channels_details')
 }
+
+// DatabaseWithoutInternals utility type
+{
+  type TestDatabaseWithInternals = {
+    __InternalSupabase: {
+      PostgrestVersion: '14'
+    }
+    public: {
+      Tables: {
+        users: {
+          Row: { id: number }
+          Insert: { id: number }
+          Update: { id?: number }
+          Relationships: []
+        }
+      }
+      Views: { [_ in never]: never }
+      Functions: { [_ in never]: never }
+      Enums: { [_ in never]: never }
+      CompositeTypes: { [_ in never]: never }
+    }
+  }
+
+  type CleanedDatabase = DatabaseWithoutInternals<TestDatabaseWithInternals>
+
+  // Should have 'public' schema
+  expectType<CleanedDatabase['public']>({} as TestDatabaseWithInternals['public'])
+
+  // Should not have '__InternalSupabase' key
+  type HasInternalKey = '__InternalSupabase' extends keyof CleanedDatabase ? true : false
+  expectType<HasInternalKey>(false)
+
+  // Should work with databases that don't have __InternalSupabase
+  type PlainDatabase = {
+    public: { Tables: {}; Views: {}; Functions: {}; Enums: {}; CompositeTypes: {} }
+  }
+  type CleanedPlainDatabase = DatabaseWithoutInternals<PlainDatabase>
+  expectType<CleanedPlainDatabase>({} as PlainDatabase)
+}