GAE DatastoreService 查询没有得到任何结果?
GAE DatastoreService Query not getting any results?
更新:如果我删除与交易相关的代码,它似乎可以工作,为什么会这样?
我在使用 GAE DatastoreService 处理简单的 hello world 时遇到了问题。我只是想把东西放进去然后列出来,下面的代码应该创建两个实体并放置它们然后查询它们并将它们列出回来。但是我没有取回清单,查询可迭代对象是空的。没有错误发生。
public static void main (String[] args) throws Throwable {
// setup HRD datastore
LocalUserServiceTestConfig lustc = new LocalUserServiceTestConfig ();
LocalDatastoreServiceTestConfig ldstc = new LocalDatastoreServiceTestConfig ();
ldstc.setDefaultHighRepJobPolicyUnappliedJobPercentage (100);
LocalServiceTestHelper helper = new LocalServiceTestHelper (lustc, ldstc).setEnvIsLoggedIn (true)
.setEnvAuthDomain ("localhost")
.setEnvEmail ("test@localhost");
helper.setUp ();
// hello world
try {
DatastoreService service = DatastoreServiceFactory.getDatastoreService ();
Entity e = new Entity ("foo");
e.setProperty ("fooey", new Text ("hello world"));
Transaction t = service.beginTransaction (withXG (true));
service.put (t, e);
e = new Entity ("bar");
e.setProperty ("bary", "goodbye world");
service.put (t, e);
t.commitAsync ().get ();
System.err.println ("foo:");
for (Entity s : service.prepare (new Query ("foo")).asIterable ())
System.err.println (s);
System.err.println ("bar:");
for (Entity s : service.prepare (new Query ("bar")).asIterable ())
System.err.println (s);
} finally {
// teardown
helper.tearDown ();
}
}
我的实际输出:
Mar 11, 2015 4:46:24 PM com.google.appengine.api.datastore.dev.LocalDatastoreService init
INFO: Local Datastore initialized:
Type: High Replication
Storage: In-memory
foo:
bar:
我希望我的实体出现在那里,为什么我看不到它们?
编辑:
我很确定这些是完成这项工作所需的 Maven 罐子:
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-api-1.0-sdk</artifactId>
<version>1.9.18</version>
</dependency>
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-testing</artifactId>
<version>1.9.18</version>
<!--scope>test</scope-->
</dependency>
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-api-stubs</artifactId>
<version>1.9.18</version>
<!--scope>test</scope-->
</dependency>
所有没有父级的查询最终都是一致的。您的 JUnit 设置告诉应用引擎永远不允许最终一致读取。特别是这一行 -
ldstc.setDefaultHighRepJobPolicyUnappliedJobPercentage (100);
改为:
ldstc.setApplyAllHighRepJobPolicy(); // 100% consistent (impractical but easy to test)
一切都会按预期进行。在生产中,您的系统将在这两个设置之间的某个位置工作。最终一致性查询将显示 "some time".
之后的数据
更新:如果我删除与交易相关的代码,它似乎可以工作,为什么会这样?
我在使用 GAE DatastoreService 处理简单的 hello world 时遇到了问题。我只是想把东西放进去然后列出来,下面的代码应该创建两个实体并放置它们然后查询它们并将它们列出回来。但是我没有取回清单,查询可迭代对象是空的。没有错误发生。
public static void main (String[] args) throws Throwable {
// setup HRD datastore
LocalUserServiceTestConfig lustc = new LocalUserServiceTestConfig ();
LocalDatastoreServiceTestConfig ldstc = new LocalDatastoreServiceTestConfig ();
ldstc.setDefaultHighRepJobPolicyUnappliedJobPercentage (100);
LocalServiceTestHelper helper = new LocalServiceTestHelper (lustc, ldstc).setEnvIsLoggedIn (true)
.setEnvAuthDomain ("localhost")
.setEnvEmail ("test@localhost");
helper.setUp ();
// hello world
try {
DatastoreService service = DatastoreServiceFactory.getDatastoreService ();
Entity e = new Entity ("foo");
e.setProperty ("fooey", new Text ("hello world"));
Transaction t = service.beginTransaction (withXG (true));
service.put (t, e);
e = new Entity ("bar");
e.setProperty ("bary", "goodbye world");
service.put (t, e);
t.commitAsync ().get ();
System.err.println ("foo:");
for (Entity s : service.prepare (new Query ("foo")).asIterable ())
System.err.println (s);
System.err.println ("bar:");
for (Entity s : service.prepare (new Query ("bar")).asIterable ())
System.err.println (s);
} finally {
// teardown
helper.tearDown ();
}
}
我的实际输出:
Mar 11, 2015 4:46:24 PM com.google.appengine.api.datastore.dev.LocalDatastoreService init
INFO: Local Datastore initialized:
Type: High Replication
Storage: In-memory
foo:
bar:
我希望我的实体出现在那里,为什么我看不到它们?
编辑:
我很确定这些是完成这项工作所需的 Maven 罐子:
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-api-1.0-sdk</artifactId>
<version>1.9.18</version>
</dependency>
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-testing</artifactId>
<version>1.9.18</version>
<!--scope>test</scope-->
</dependency>
<dependency>
<groupId>com.google.appengine</groupId>
<artifactId>appengine-api-stubs</artifactId>
<version>1.9.18</version>
<!--scope>test</scope-->
</dependency>
所有没有父级的查询最终都是一致的。您的 JUnit 设置告诉应用引擎永远不允许最终一致读取。特别是这一行 -
ldstc.setDefaultHighRepJobPolicyUnappliedJobPercentage (100);
改为:
ldstc.setApplyAllHighRepJobPolicy(); // 100% consistent (impractical but easy to test)
一切都会按预期进行。在生产中,您的系统将在这两个设置之间的某个位置工作。最终一致性查询将显示 "some time".
之后的数据