split query resolvers into separate files

src/index.ts

@@ -1,7 +1,7 @@
 import { readFileSync } from "fs";
 import { ApolloServer } from "@apollo/server";
 import { startStandaloneServer } from "@apollo/server/standalone";
-import { resolvers } from "./resolvers";
+import { MergedResolvers } from "./resolvers";
 import { ServerContext } from "./ServerContext";
 import { UnoptimizedInMemoryRepository } from "./repositories/UnoptimizedInMemoryRepository";
 import { TimedApiBasedRepositoryLoader } from "./loaders/TimedApiBasedRepositoryLoader";
@@ -11,7 +11,7 @@ const typeDefs = readFileSync("./schema.graphqls", "utf8");
 async function main() {
   const server = new ApolloServer<ServerContext>({
     typeDefs,
-    resolvers,
+    resolvers: MergedResolvers,
     introspection: process.env.NODE_ENV !== "production",
   });
 

src/mergedResolvers.ts

@@ -1,29 +1,9 @@
 import { Coordinates, Eta, OrderedStop, Resolvers } from "./generated/graphql";
 import { ServerContext } from "./ServerContext";
+import { QueryResolvers } from "./resolvers/QueryResolvers";
 
-export const resolvers: Resolvers<ServerContext> = {
-  Query: {
-    systems: async (parent, args, contextValue, info) => {
-      const systems = await contextValue.repository.getSystems();
-      return systems.map(({
-        name,
-        id
-      }) => ({
-        name,
-        id
-      }));
-    },
-    system: async (parent, args, contextValue, info) => {
-      if (!args.id) return null;
-      const system = await contextValue.repository.getSystemById(args.id);
-      if (system === null) return null;
-
-      return {
-        name: system.name,
-        id: system.id,
-      };
-    }
-  },
+export const MergedResolvers: Resolvers<ServerContext> = {
+  ...QueryResolvers,
   System: {
     routes: async (parent, args, contextValue, info) => {
       return await contextValue.repository.getRoutesBySystemId(parent.id);

src/resolvers/QueryResolvers.ts

@@ -0,0 +1,20 @@
+import { ServerContext } from "../ServerContext";
+import { Resolvers } from "../generated/graphql";
+
+export const QueryResolvers: Resolvers<ServerContext> = {
+  Query: {
+    systems: async (parent, args, contextValue, info) => {
+      return await contextValue.repository.getSystems();
+    },
+    system: async (parent, args, contextValue, info) => {
+      if (!args.id) return null;
+      const system = await contextValue.repository.getSystemById(args.id);
+      if (system === null) return null;
+
+      return {
+        name: system.name,
+        id: system.id,
+      };
+    }
+  },
+}