驱动程序配置

此页面描述了 Neo4j GraphQL 库驱动程序的配置。

Neo4j 驱动程序

要使 Neo4j GraphQL 库正常工作，必须在 Neo4jGraphQL 实例（或 OGM）的构造过程中传入 Neo4j JavaScript 驱动程序 的实例，或者在每次请求时将驱动程序、会话或事务传入 context.executionContext。

此页面中的示例假设 Neo4j 数据库在“bolt://localhost:7687”上运行，用户名为“username”，密码为“password”。

Neo4j GraphQL 库

Neo4jGraphQL 构造函数中的驱动程序

import { ApolloServer } from "@apollo/server";
import { startStandaloneServer } from "@apollo/server/standalone";
import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });

const server = new ApolloServer({
    schema: await neoSchema.getSchema(),
});

await startStandaloneServer(server, {
    context: async ({ req }) => ({ req }),
});

上下文中的驱动程序

import { ApolloServer } from "@apollo/server";
import { startStandaloneServer } from "@apollo/server/standalone";
import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });

const server = new ApolloServer({
    schema: await neoSchema.getSchema(),
});

await startStandaloneServer(server, {
    context: async ({ req }) => ({ req, executionContext: driver }),
});

上下文中的会话

import { ApolloServer } from "@apollo/server";
import { startStandaloneServer } from "@apollo/server/standalone";
import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);
const session = driver.session();

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });

const server = new ApolloServer({
    schema: await neoSchema.getSchema(),
});

await startStandaloneServer(server, {
    context: async ({ req }) => ({ req, executionContext: session }),
});

上下文中的事务

import { ApolloServer } from "@apollo/server";
import { startStandaloneServer } from "@apollo/server/standalone";
import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);
const session = driver.transaction();
const transaction = session.beginTransaction();

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });

const server = new ApolloServer({
    schema: await neoSchema.getSchema(),
});

await startStandaloneServer(server, {
    context: async ({ req }) => ({ req, executionContext: transaction }),
});

OGM

import { OGM } from "@neo4j/graphql-ogm";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const ogm = new OGM({ typeDefs, driver });

数据库兼容性

使用 Neo4jGraphQL 或 OGM 实例上可用的 checkNeo4jCompat 方法来确保指定的 DBMS 具有所需的版本，并且具有必要的可用函数和过程。如果 DBMS 不兼容，checkNeo4jCompat 将抛出 Error，其中包含不兼容性的详细信息。

Neo4jGraphQL

import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });
await neoSchema.checkNeo4jCompat();

OGM

import { OGM } from "@neo4j/graphql-ogm";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const ogm = new OGM({ typeDefs, driver });
await ogm.checkNeo4jCompat();

指定 Neo4j 数据库

通过 context 中的 sessionConfig 下的 database 字段指定要在 DBMS 中使用的数据库，所有解析器都共享该 context。

import { ApolloServer } from '@apollo/server';
import { startStandaloneServer } from '@apollo/server/standalone';
import { Neo4jGraphQL } from "@neo4j/graphql";
import neo4j from "neo4j-driver";

const typeDefs = `#graphql
    type User {
        name: String
    }
`;

const driver = neo4j.driver(
    "bolt://localhost:7687",
    neo4j.auth.basic("username", "password")
);

const neoSchema = new Neo4jGraphQL({ typeDefs, driver });

const server = new ApolloServer({
    schema: await neoSchema.getSchema(),
});

await startStandaloneServer(server, {
    context: async ({ req }) => ({ req, sessionConfig: { database: "my-database" }}),
});