将Neo4j Javascript驱动程序导入角2 CLI时出错

Question

头盔，我有一些模块没有发现错误，而试图使用Neo4j驱动程序在我的角度2 CLI应用程序。

我可能漏掉了什么东西试图导入它。

• 我安装它的时候：ng安装了新4j驱动程序。
• 在我的service.ts：import 'neo4j-driver/lib/browser/neo4j-web';中
• 试图在服务中调用此示例代码： getFromDB()：void{ var neo4j =需要量(‘ne4j-neo4j’).v1；var driver = neo4j.driver("bolt: // localhost"，neo4j.auth.basic("neo4j"，"pisikopat"))；//创建一个会话来运行Cypher语句。//注意:始终确保在使用完会话后关闭它们！var session = driver.session ()；//运行Cypher语句，在记录到达时以流式方式读取结果：.run(“可选匹配(源)-r-(目标)”，其中r不是空返回(源)“) .subscribe({ onNext: function (record) { console.log(record._fields)；}，onCompleted: function (){ // Completed！session.close()；}，onError:函数(错误){console.log(错误)；}}；}

当我ng服务我的应用程序时，我会得到以下错误：

ERROR in ./~/neo4j-driver/lib/v1/internal/ch-node.js
Module not found: Error: Can't resolve 'net' in 'E:\emek\node_modules\neo4j-driver\lib\v1\internal'
 @ ./~/neo4j-driver/lib/v1/internal/ch-node.js 32:11-25 364:2-24
 @ ./~/neo4j-driver/lib/v1/internal/connector.js
 @ ./~/neo4j-driver/lib/v1/driver.js
 @ ./~/neo4j-driver/lib/v1/index.js
 @ ./~/neo4j-driver/lib/index.js
 @ ./src/app/services/heroes.service.ts
 @ ./src/app/app.component.ts
 @ ./src/app/index.ts
 @ ./src/main.ts
 @ multi main

ERROR in ./~/neo4j-driver/lib/v1/internal/ch-node.js
Module not found: Error: Can't resolve 'tls' in 'E:\emek\node_modules\neo4j-driver\lib\v1\internal'
 @ ./~/neo4j-driver/lib/v1/internal/ch-node.js 36:11-25
 @ ./~/neo4j-driver/lib/v1/internal/connector.js
 @ ./~/neo4j-driver/lib/v1/driver.js
 @ ./~/neo4j-driver/lib/v1/index.js
 @ ./~/neo4j-driver/lib/index.js
 @ ./src/app/services/heroes.service.ts
 @ ./src/app/app.component.ts
 @ ./src/app/index.ts
 @ ./src/main.ts
 @ multi main

ERROR in ./~/neo4j-driver/lib/v1/internal/ch-node.js
Module not found: Error: Can't resolve 'readline' in 'E:\emek\node_modules\neo4j-driver\lib\v1\internal'
 @ ./~/neo4j-driver/lib/v1/internal/ch-node.js 92:2-21
 @ ./~/neo4j-driver/lib/v1/internal/connector.js
 @ ./~/neo4j-driver/lib/v1/driver.js
 @ ./~/neo4j-driver/lib/v1/index.js
 @ ./~/neo4j-driver/lib/index.js
 @ ./src/app/services/heroes.service.ts
 @ ./src/app/app.component.ts
 @ ./src/app/index.ts
 @ ./src/main.ts
 @ multi main

角-cli: 1.0.0-beta.15节点:4.5.0os: win32 x64

Answer 1

这可能有点晚了，但无论如何都到了。

首先，您需要改变导入和分配驱动程序的方式。更改：

import 'neo4j-driver/lib/browser/neo4j-web';

至：

import * as neo4j_driver from 'neo4j-driver/lib/browser/neo4j-web.min.js';

然后更改节点外观语法：

var neo4j = require('neo4j-driver').v1;

至：

const neo4j = neo4j_driver.v1;

这将消除您所犯的错误。

然后，实际上您可能会因为没有在uri中分配端口而出现错误。为了获得正确的端口(7474对我不起作用)，我启动了DB并转到localhost:7474的Neo4j浏览器。然后，您必须向下查看页面，其中写着“您作为用户neo4j连接到服务器螺栓://localhost:7687”--我不确定这是默认的还是被分配的，但无论如何。

然后，我在uri中使用了这个端口，而且所有东西现在都在角内工作(尽管如果使用远程连接(例如使用Graphene，并且我找到的唯一文档不适用于JS驱动程序)，则无法使其工作)。

以下是我的完整解决方案：

import {Component, OnInit} from '@angular/core';
import * as neo4j_driver from 'neo4j-driver/lib/browser/neo4j-web.min.js';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent implements OnInit {
  title = 'app works!';

  constructor() {
  }

  ngOnInit() {
    const neo4j = neo4j_driver.v1;
    const uri = 'bolt://localhost:7687';
    const user = 'neo4j';
    const password = '<your password>';
    const driver = neo4j.driver(uri, neo4j.auth.basic(user, password), {maxTransactionRetryTime: 15000});

    // Register a callback to know if driver creation was successful:
    driver.onCompleted = function () {
    // proceed with using the driver, it was successfully instantiated
    };
    // Register a callback to know if driver creation failed.
    // This could happen due to wrong credentials or database unavailability:
    driver.onError = function (error) {
      console.log('Driver instantiation failed', error);
    };

    const session = driver.session();
    const result = session.run('MATCH (a:Person) RETURN a.name ORDER BY a.name');
    const people = [];

    result.subscribe({
      onNext: record => {
        const name = record.get(0);
        people.push(name);
      },
      onCompleted: () => {
        session.close();
        console.log(people);
      },
      onError: error => {
        console.log(error);
      }
    });
  }
}