无法获取图形查询语言工具来读取我的schema.graphql文件

Question

我使用的是Apollo-server-express和Graphql工具。我已经看遍了Graphql-tools文档，但我不能让它工作。我正在尝试将我的schema.graphql文件作为我的typeDefs导入。看起来Graphql工具应该让这件事变得简单，但有些东西并没有落到合适的位置。

index.js

const { ApolloServer } = require("apollo-server-express");
const { makeExecutableSchema } = require('@graphql-tools/schema');
const express = require("express");
const { join } = require("path");
const { loadSchema } = require("@graphql-tools/load");
const { GraphQLFileLoader } = require("@graphql-tools/graphql-file-loader");
const { addResolversToSchema } = require("@graphql-tools/schema");
const app = express();

const resolvers = {
  Query: {
    items: (parent, args, ctx, info) => {
      return ctx.prisma.item.findMany();
    },
  },
  Mutation: {
    makeItem: (parent, args, context, info) => {
      const newItem = context.prisma.item.create({
        data: {
          ...args,
          price: parseInt(Math.ceil(args.price * 100)),
        },
      });
      return newItem;
    },
    deleteItem: (parent, args, context, info) => {
      return context.prisma.item.delete({
        where: {
          id: args.id,
        },
      });
    },
  },
};

const schemaSource = loadSchemaSync(join(__dirname, "schema.graphql"), {
  loaders: [new GraphQLFileLoader()],
});

const schema = makeExecutableSchema({
  typeDefs: schemaSource,
  resolvers,
});

const server = new ApolloServer({
  schema,
  resolvers,
});

server.applyMiddleware({ app });

app.listen(
  { port: 4000 },
  () =>
    console.log(
      `? => Backend server is now running on port http://localhost:4000`
    )
);

schema.graphql

type Query {
  items: [Item!]!
}

type Mutation {
  makeItem(
    piece: String!
    image: String!
    identifier: String!
    price: Float!
    itemNumber: Int!
  ): Item!
  deleteItem(id: ID!): Item!
}

type Item {
  id: ID!
  piece: String!
  image: String!
  identifier: String!
  price: Int!
  itemNumber: Int!
}

在它的当前状态下，我得到一个错误消息：" error : typeDefs必须是一个字符串、数组或schema AST，got对象“

据我所知，makeExecutableSchema应该执行所有必要的步骤，比如将模式更改为字符串。我似乎不知道这里发生了什么，任何帮助都将不胜感激。

Answer 1

loadSchemaSync将使用提供的指针加载GraphQLSchema对象。您应该改用loadTypedefsSync。

const sources = loadTypedefsSync(join(__dirname, "schema.graphql"), {
  loaders: [new GraphQLFileLoader()],
});
const typeDefs = sources.map(source => source.document)
const server = new ApolloServer({ typeDefs, resolvers })

如果您想使用loadSchema，则不需要使用makeExecutableSchema，因为您的模式已经创建。因此，您应该按照docs中所示的方式执行此操作

const schema = loadSchemaSync(join(__dirname, "schema.graphql"), {
  loaders: [new GraphQLFileLoader()],
});

const resolvers = {...};
const schemaWithResolvers = addResolversToSchema({
    schema,
    resolvers,
});
const server = new ApolloServer({ schema: schemaWithResolvers })