图形质量从Oracle DB中提取数据:查询响应结果集，但未出现在Graphql解析器窗口中 [英] GraphQL & Pulling Data from Oracle DB: Query Responds with the Resultset and Doesn't Come to The Graphql resolver Window

问题描述

我是GraphQL的新手.

I am new to GraphQL.

开始开发GraphQL应用程序以从oracle数据库中提取数据.

Started developing an GraphQL app to pull the data from oracle database.

这是一个非常简单的应用程序.查询以resultset响应，并且可以在console.log中看到结果；但是，它不会出现在graphql窗口(响应/解析器窗口)中.引发错误

It is very simple application. The query responds with the resultset and can be seen results in console.log; however, it doesn't come to the graphql window (response/resolver window). It throws the error

对于非User.email不能返回null

Cannot return null for non User.email

我在oracle连接中尝试了promise.不确定，为什么它不在GraphQL中显示数据.

I tried the promise in the oracle connection. Not sure, why it is not showing the data in GraphQL.

UserType.js

UserType.js

module.exports = new GraphQLObjectType({
  name: 'User',

  fields: () => {
    return{
      id: { type: GraphQLID },
      email: { type: new GraphQLNonNull(GraphQLString) }
    }
  }
});

DBConnection.js

DBConnection.js

module.exports = oraPool => {
  return  {
    getUsers(apiKey){
      return oracledb.createPool(oraConfig).then(function() {
    console.log("Connection Pool created");
    return oracledb.getConnection().then(function(conn) {
      return conn.execute(
        //`SELECT 'User ' || JSON_OBJECT ('id' VALUE id, 'email' VALUE email) FROM users where id = :id`
        `SELECT  * FROM users WHERE id = :id`
        ,[apiKey]).then(result => {
          //console.log(result.metaData);
          console.log(humps.camelizeKeys(result.rows[0]));
          conn.close();
          return humps.camelizeKeys(result.rows[0]);
        })
        .catch(function(err) {
          console.log(err.message);
          return connection.close();
        });
      })
      .catch(function(err) {
        console.error(err.message);
      });
    })
      }
    }
  }

Type.js

const RootQueryType = new GraphQLObjectType({
  name: 'RootQueryType',

  fields: {
    user: {
      type: UserType,
      args: {
    key: { type: new GraphQLNonNull(GraphQLString) }
      },
      resolve: (obj, args, { oraPool }) => {
    return oradb(oraPool).getUsers(args.key);
      }

    }
  }
});

推荐答案

这段代码很复杂，我建议从头开始.例如，您每次运行查询时都在调用createPool.您应该在应用初始化期间创建池.

This code is pretty tangled, I recommend starting from scratch. For example, you're calling createPool each time a query is run. You should create the pool during the initialization of your app instead.

尽管您说这将是一个简单的应用程序，但它可能会不断发展.从头开始创建GraphQL服务器并非易事.我建议通过join-monster带来一些帮助.不幸的是，join-monster不再被积极开发.但是它非常稳定，比从头开始要好得多.这是一个很好的工作原理概述: https://github.com/stems/join-monster/tree/master/src

Although you said this will be a simple app, it could always grow. Creating a from scratch GraphQL server isn't trivial. I recommend bringing in some help via join-monster. Unfortunately, join-monster is no longer being actively developed. But it's pretty stable and it's a lot better than starting from scratch. Here's a nice overview of how it works: https://github.com/stems/join-monster/tree/master/src

我最近在GraphQL上进行了演讲，您可以在这里看到:

I recently did a talk on GraphQL which you can see here: https://www.slideshare.net/DanielMcGhan/intro-to-graphql-for-database-developers

对于该演示，我采用了一个简单的API模式，该模式在 https://www.dropbox.com/s/cnvyrlik7irtbwm/graphql-api.zip?dl=0

For the demo, I took a simple API pattern I describe in this blog series and adapted it to be a GraphQL server on the common EMP and DEPT demo tables. You can access the code here: https://www.dropbox.com/s/cnvyrlik7irtbwm/graphql-api.zip?dl=0

此外，我的另一位同事在这里谈论GraphQL: https://blogs.oracle.com/opal/demo:- graphql-with-node-oracledb

Also, another one of my colleagues talks about GraphQL here: https://blogs.oracle.com/opal/demo:-graphql-with-node-oracledb

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