[28] Window PowerShell DSC 学习系列----如何用Java调用PowerShell DSC 5.x的oData服务

PowerShell DSC 5.x的Report是基于OData V3的标准，而这个标准是微软提出已经标准化的一个开放的工业标准。在我的另外一篇文章中也提到了有下面的几个Java的开源框架支持调用oData的服务。

Apache Olingo： V2 and V4
SDL OData 框架：V4
odata4j： V1-V3
ODataJClient：V3
Jello 框架： Jello 框架

1.介绍

因为PowerShell DSC 5.x的Report是基于OData V3的标准,所以理论上只有odata4j和ODataJClient的框架支持V3版本；但是实际上odata4j宣传支持，其实代码并没有实现。经过研究论证，只有ODataJClient能够支持PowerShell DSC 5.x的Report是基于OData V3的标准的调用。其核心Jar主要包括两个。

2.Maven或者Gradle依赖

如果我们需要使用，则在我们的Gradle或者Maven文件里面，只需要引入odatajclient-engine，odatajclient-engine-xml会自动引入。
<dependency>
<groupId>com.msopentech.odatajclient</groupId>
<artifactId>odatajclient-engine</artifactId>
<version>0.9.0</version>
</dependency>

当前的release版本是0.9.0，当前正在开发的版本是0.9.1-snapshot，感兴趣的朋友可以到下面的网站去Fork代码 https://github.com/mkostin/ODataJClient

3.使用的前提条件

注意使用的前提条件是：

Apache Maven >= 3.0.3
JDK >= 1.6.0-23

4.代码例子

下面给出1个调用的例子代码，
import java.util.List;
import org.junit.Test;
import com.msopentech.odatajclient.engine.communication.request.retrieve.ODataEntitySetRequest;
import com.msopentech.odatajclient.engine.communication.request.retrieve.ODataRetrieveRequestFactory;
import com.msopentech.odatajclient.engine.communication.response.ODataRetrieveResponse;
import com.msopentech.odatajclient.engine.data.ODataCollectionValue;
import com.msopentech.odatajclient.engine.data.ODataEntity;
import com.msopentech.odatajclient.engine.data.ODataEntitySet;
import com.msopentech.odatajclient.engine.data.ODataLink;
import com.msopentech.odatajclient.engine.data.ODataProperty;
import com.msopentech.odatajclient.engine.format.ODataPubFormat;
import com.msopentech.odatajclient.engine.uri.ODataURIBuilder;

public class RequestEntityTest {
String testODataServiceRootURL="http://dsc-server:8080/PSDSCPullServer.svc/";
@Test
public void testName() throws Exception {
ODataURIBuilder uriBuilder = new ODataURIBuilder(testODataServiceRootURL).appendEntityTypeSegment("Nodes(AgentId='304DC9EE-12D4-11E7-80B8-B9D2EE16DFG9')/Reports");

ODataEntitySetRequest req = ODataRetrieveRequestFactory.getEntitySetRequest(uriBuilder.build());
req.setFormat(ODataPubFormat.ATOM);
ODataRetrieveResponse<ODataEntitySet> res = req.execute();

res.getStatusCode();
res.getStatusMessage();
res.getContentType();
res.getEtag();
res.getHeaderNames();
res.getHeader("DataServiceVersion");

ODataEntitySet entitySet = res.getBody();
System.out.println(entitySet.getCount());
ODataEntity entity=entitySet.getEntities().get(0);

List<ODataLink> lsODataLink= entity.getAssociationLinks();

lsODataLink.forEach( ODataLink ->
{
System.out.println("%%%%%%%%%%%%%%%%%%%%%%%%%%%");
System.out.println(ODataLink);
}

);

ODataProperty oDataPropertyJobID=entity.getProperty("JobId");
System.out.println(".........oDataPropertyJobID:"+oDataPropertyJobID.getValue());

List<ODataProperty> properties = entity.getProperties();

properties.forEach(oDataProperty ->{
System.out.println("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
System.out.println(oDataProperty.getValue());
if( oDataProperty.hasCollectionValue()){
System.out.println("---hasCollectionValue---");
System.out.println(oDataProperty.getName());
ODataCollectionValue oDataCollectionValue= oDataProperty.getCollectionValue();
System.out.println(oDataCollectionValue.getTypeName());
System.out.println(oDataProperty.getPrimitiveValue());
}

if(oDataProperty.hasComplexValue()){
System.out.println("---hasComplexValue---");
System.out.println(oDataProperty.getName());
}

});
}
}

注意，下面的代码，没有和DSC Report OData直接相关，但是显示的是示范代码，调用过程类似，另外需要注意的是DSC Report的查询不支持OData的filter的语法，如果要让其支持，请自己定义实现：

@获取单个的实体

ODataURIBuilder uriBuilder = new ODataURIBuilder(testODataServiceRootURL).
appendEntityTypeSegment("Customer(1)");

ODataEntityRequest req = ODataRetrieveRequestFactory.getEntityRequest(uriBuilder.build());
req.setFormat(ODataPubFormat.JSON_FULL_METADATA);

ODataRetrieveResponse<ODataEntity> res = req.execute();

res.getStatusCode();
res.getStatusMessage();
res.getContentType();
res.getEtag();
res.getHeaderNames();
res.getHeader("DataServiceVersion");

ODataEntity entity = res.getBody();

URI editLink = entity.getEditLink();
List<ODataProperty> properties = entity.getProperties();
ODataProperty property = entity.getProperty("Id");
List<ODataLink> navLinks = getNavigationLinks();
List<ODataLink> assLinks = getAssociationLinks();
List<ODataLink> meLinks = getEditMediaLinks();
List<ODataOperation> operations = getOperations();

@获取实体集

ODataURIBuilder uriBuilder = new ODataURIBuilder(testODataServiceRootURL).
appendEntitySetSegment("Car").top(3);

ODataEntitySetRequest req = ODataRetrieveRequestFactory.getEntitySetRequest(uriBuilder.build());

ODataRetrieveResponse<ODataEntitySet> res = req.execute();
ODataEntitySet entitySet = res.getBody();

URI nextPageLink = getNext();
List<ODataEntity> entities = getEntities();

@Filter的过滤查询

ODataURIBuilder uriBuilder = new ODataURIBuilder(testODataServiceRootURL).
appendEntityTypeSegment("Car").filter("VIN lt 16");

ODataEntitySet result = ODataRetrieveRequestFactory.getEntitySetRequest(
uriBuilder.build()).execute().getBody();
具体的查询格式，请参考微软的一篇文章：https://msdn.microsoft.com/en-us/library/dd541437.aspx

@Basic认证调用

// instructs ODataJClient to send a BasicAuth HTTP header
// for username 'sampleUsername' and password ' samplePassword'
Configuration.setHttpClientFactory(new AbstractBasicAuthHttpClientFactory() {

@Override
protected String getUsername() {
return "sampleUsername";
}

@Override
protected String getPassword() {
return "samplePassword";
}
});

// perform any operation via ODataJClient: all requests will bear the BasicAuth HTTP header

// this restores the default unauthenticated behavior
Configuration.setHttpClientFactory(new DefaultHttpClientFactory());

参考文献：

https://github.com/mkostin/ODataJClient/wiki/User-guide-(Engine)
http://blog.csdn.net/chancein007/article/details/54016636 https://github.com/mkostin/ODataJClient