0

这可能比它需要的要复杂一些，但我正在使用：

  • MongoDB数据库
  • 火花
  • 自由标记
  • 爪哇

我无法弄清楚如何访问 mongodb 中的嵌入数据以在网站上打印。我希望能够查看记录，找到哪个接口有一个值为“MGMT”的“标签”，然后打印该接口的信息。问题是，我将它们嵌入到“网络”集合中。我如何访问该信息？

重要的代码行：

爪哇：

try {
                        Template helloTemplate = configuration.getTemplate("hello.ftl");

                        DBObject document = collection.findOne();



                        helloTemplate.process(document, writer);

                        System.out.println(writer);
                    } catch (Exception e) {
                        halt(500);
                        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
                    }

完整代码：

.java：

import com.mongodb.*;
import freemarker.template.Configuration;
import freemarker.template.Template;
import spark.Request;
import spark.Response;
import spark.Route;
import spark.Spark;

import java.io.StringWriter;
import java.net.UnknownHostException;
import java.util.HashMap;
import java.util.Map;

/**
 * Created with IntelliJ IDEA.
 * User: sysrjt1
 * Date: 6/13/13
 * Time: 1:09 PM
 * To change this template use File | Settings | File Templates.
 */
public class HelloWorldMongoDBSparkFreemarkerSyle {
    public static void main(String[] args) {
        final Configuration configuration = new Configuration();
        configuration.setClassForTemplateLoading(HelloWorldMongoDBSparkFreemarkerSyle.class, "/");

        MongoClient client = null;
        try {
            client = new MongoClient(new ServerAddress("localhost", 27017 ));
        } catch (UnknownHostException e) {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }

        DB database = client.getDB("systems");
        final DBCollection collection;
        collection = database.getCollection("systems");

        Spark.get(new Route("/") {
            @Override
            public Object handle(Request request, Response response) {
                StringWriter writer = new StringWriter();
                try {
                    Template helloTemplate = configuration.getTemplate("hello.ftl");

                    DBObject document = collection.findOne();



                    helloTemplate.process(document, writer);

                    System.out.println(writer);
                } catch (Exception e) {
                    halt(500);
                    e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
                }
                return writer;
            }
        });
    }
}

我的 HTML 模板（hello.ftl）：

<!DOCTYPE html>
<html>
<head>
    <title>Welcome!</title>
</head>
<body>
    <table>
        <thead>
            <tr>
                <th>Name</th>
                <th>Management IP</th>
                <th>RAM</th>
            </tr>
        </thead>
        <tbody>
            <tr>
                <td>${name}</td>
                <td>${ipAddr}</td> <! -- this line fails -->
                <td>${ram}</td>
            </tr>
        </tbody>
    </table>

     <h1>Server Name: ${name}</h1>
</body>
</html>

来自 MongoDB：

> db.systems.findOne()
{
        "_id" : ObjectId("51b9dde5d05f675ad37ac990"),
        "name" : "abcdev01",
        "networking" : {
                "interface1" : {
                        "name" : "eth0",
                        "ipAddr" : "12.34.45.56",
                        "sNet" : "255.255.255.0",
                        "label" : "MGMT"
                },
                "interface2" : {
                        "name" : "eth1",
                        "ipAddr" : "1.2.3.4"
                }
        },
        "ram" : 102390
}
4

2 回答 2

1

我猜（不知道 MongoDB）失败的行应该是${networking.interface1.ipAddr}. 但可能您想列出所有接口。那么也许你可以这样做：

<#list networing.keySet() as ifname>
  ...
  ${networking[ifname].ipAddr}
  ...
</#list>

虽然，如果您只想打印有关具有给定名称的接口的信息，您应该使用 MongoDB API 发出正确的查询，并且只将该单个接口对象传递给 FreeMarker。

于 2013-06-13T23:04:14.657 回答
0

我想出了我需要的（我认为）java文件：

imports...
public class PACManTest {
    public static void main(String[] args) throws UnknownHostException {
        final Configuration configuration = new Configuration();
        configuration.setClassForTemplateLoading(PACManTest.class, "/");

        MongoClient client = new MongoClient(new ServerAddress("localhost", 27017 ));

        DB database = client.getDB("pacman");
        final DBCollection collection = database.getCollection("servers");

        DBObject document = collection.findOne();
        DBObject tempDoc = new BasicDBObject(); //THIS LINE    

//BELOW FROM : http://stackoverflow.com/questions/10345788/retrieve-sub-document-in-array-as-dbobjects

        BasicDBList networking = (BasicDBList) document.get("networking");
        //System.out.println("networking = " + networking.toString());
        BasicDBObject[] networkArr = networking.toArray(new BasicDBObject[0]);
        String mip = new String();
        for (BasicDBObject dbObj : networkArr) {
            if (dbObj.containsValue("MGMT")){
                 mip =  dbObj.get("ip").toString();
            } else {
               //nothing for right now
            }
        }
        tempDoc = new BasicDBObject().append("name", document.get("name")).append("ram", document.get("ram")).append("mip", mip);

final DBObject finalDocument = tempDoc; //put the temp doc into a final doc
        Spark.get(new Route("/") {
            @Override
            public Object handle(Request request, Response response) {
                StringWriter writer = new StringWriter();
                try {
                    Template PACManTemplate = configuration.getTemplate("pacman.ftl");
                    PACManTemplate.process(finalDocument, writer); //write to the template
                } catch (Exception e) {
                    halt(500);
                    e.printStackTrace();
                }
                return writer;
            }
        });

    }
}

这适用于给定的 ftl：

<table>
    <thead>
    <tr>
        <th>Name</th>
        <th>MGMT IP</th>
        <th>Ram</th>
    </tr>
    </thead>
    <tbody>
        <tr>
            <td>${name}</td>
            <td>${mip}</td>
            <td>${ram}</td>
        </tr>
    </tbody>
</table>

我仍然必须弄清楚如何使用多个对象来做到这一点......我在想 DBObjectList 或者可能是一段时间（cursor.hasNext（））或其他东西，但这是对这个当前问题的答案。

于 2013-06-14T22:05:41.697 回答