Loopback discoverAndBuildModels不生成模型

Question

我正在尝试让Loopback发现并构建我的第一个表.我在他们的页面底部使用了这个简单的例子:

http://docs.strongloop.com/display/LB/Database+discovery+API#DatabasediscoveryAPI-Exampleofbuildingmodelsviadiscovery

我看到了我正在发现的表的输出,但API Explorer没有显示表或任何新生成的端点.此外,不使用新表对象更新model-config.js文件.以下是在服务器启动时完成的代码的基本部分:

var loopback = require('loopback');
var boot = require('loopback-boot');
var DataSource = require('loopback-datasource-juggler').DataSource;
var mysqlSource = require('./datasources.json');
var dataSource = new DataSource('mssql', mysqlSource.mysqlserver);

var app = module.exports = loopback();

// Set up the /favicon.ico
app.use(loopback.favicon());

// request pre-processing middleware
app.use(loopback.compress());

// -- Add your pre-processing middleware here --

dataSource.discoverAndBuildModels('CATS', {owner: 'mamacat'}, function (err, models) {
    models.Cat.find(function (err, cat) {
        if (err) {
            console.error(err);
        } else {
            console.log(cat);
        }
        dataSource.disconnect();
    });
});

// boot scripts mount components like REST API
boot(app, __dirname);

总而言之,这样运行,没有错误.但没有新的模型显示http://localhost:3000/explorer

Answer 1

似乎发现脚本仅显示输出并且不创建模型文件.我在loopback docs上找到了一些说明:

http://docs.strongloop.com/display/public/LB/Discovering+models+from+relational+databases

在基本程序一节中,第二步:

2.使用fs.writeFile()将输出保存在common/models/model-name.json中.

所以你可以尝试以下方法:

1. 在yourloopbackproject/server/datasources.json文件中设置mysql数据:

{
  "db": {
    "name": "db",
    "connector": "memory"
  },
  "accountDs": {
    "host": "mysqlServerName",
    "port": 3306,
    "database": "databaseName",
    "username": "username",
    "password": "password!",
    "name": "accountDs",
    "connector": "mysql"
  }
}

2. 如果不存在,则创建models文件夹:yourloopbackproject/common/models.

3. 在yourloopbackproject/server/bin文件夹上创建discovery-and-build.js脚本:

var path = require('path');
var fs = require('fs');
var app = require(path.resolve(__dirname, '../server'));
var outputPath = path.resolve(__dirname, '../../common/models');

var dataSource = app.dataSources.accountDs;

function schemaCB(err, schema) {
  if(schema) {
    console.log("Auto discovery success: " + schema.name);
    var outputName = outputPath + '/' +schema.name + '.json';
    fs.writeFile(outputName, JSON.stringify(schema, null, 2), function(err) {
      if(err) {
        console.log(err);
      } else {
        console.log("JSON saved to " + outputName);
      }
    });
  }
  if(err) {
    console.error(err);
    return;
  }
  return;
};

dataSource.discoverSchema('tableName',{schema:'schemaName'},schemaCB);

此脚本基于:http://www.reddit.com/r/strongloop/comments/2upy76/autodiscoveryjs_recipe/

4. 脚本执行后,您将在models文件夹中找到.json文件.转到基本过程部分的步骤3 :http: //docs.strongloop.com/display/public/LB/Discovering+models+from+relational+databases

5. 按照以下步骤通过REST公开您的模型:http: //docs.strongloop.com/display/public/LB/Exposing+models+over+REST

我希望这有帮助!