How to modularize schema

[ssmilin]

How to modularize schema using gql provided by apollo. How to write schema in separate file and stitch it
type Rocket {
id: ID!
name: String
type: String
}

type User {
id: ID!
email: String!
trips: [Launch]!
token: String
}

type Mission {
name: String
missionPatch(size: PatchSize): String
}

enum PatchSize {
SMALL
LARGE
}

[KeithGillette]

I built a simple service class to accomplish this in our Apollo Server project, but the logic of getSchemas should be all you need, since it's actually stateless.

import { gql } from 'apollo-angular';
import { readdirSync, readFileSync, statSync } from 'fs';
import { join } from 'path';
import { DocumentNode } from 'graphql';

import { Service } from '../infrastructure/decorators/service.decorator';


const schemaFolder = 'assets/app/core/application/schema';

/** Injectable() service providing GraphQL schema array */
@Service()
export class SchemaService {
	public getSchemas(): DocumentNode[] {
		function buildFilePathList(directoryPath: string): string[] {
			const directoryEntryList = readdirSync(directoryPath);
			const filePathList = [];
			for (const directoryEntry of directoryEntryList) {
				const pathToEntry = join(directoryPath, directoryEntry);
				const isDirectory = statSync(pathToEntry).isDirectory();
				if (isDirectory) {
					filePathList.push(...buildFilePathList(pathToEntry));
				} else {
					filePathList.push(pathToEntry);
				}
			}
			return filePathList;
		}

		return buildFilePathList(schemaFolder)
			.map((filePath: string) => {
				return gql(readFileSync(filePath).toString());
			});
	}
}

Call getSchemas() when creating your ApolloServer instance:

new ApolloServer({
	typeDefs: this.schemaService.getSchemas(),
	// …
});