feat: optional payment for server (#5055)

packages/backend/server/src/modules/config.ts

@@ -0,0 +1,30 @@
+import { Module } from '@nestjs/common';
+import { Field, ObjectType, Query } from '@nestjs/graphql';
+
+import { SERVER_FLAVOR } from '../modules';
+
+@ObjectType()
+export class ServerConfigType {
+  @Field({ description: 'server version' })
+  version!: string;
+
+  @Field({ description: 'server flavor' })
+  flavor!: string;
+}
+
+export class ServerConfigResolver {
+  @Query(() => ServerConfigType, {
+    description: 'server config',
+  })
+  serverConfig(): ServerConfigType {
+    return {
+      version: AFFiNE.version,
+      flavor: SERVER_FLAVOR || 'allinone',
+    };
+  }
+}
+
+@Module({
+  providers: [ServerConfigResolver],
+})
+export class ServerConfigModule {}