appengine
java night #2
α
shin1ogawa@

AppEngine
AppEngine
ApiProxy#getDelegate()
Delegate
Web Delegate
Web
ApiProxy
#getCurrentEnvironment()
Environment
(ApplicationID, versionID )

AppEngine
JUnit SDK Web
ApiProy
• Environment
ApiProxy#setEnvironmentForCurrentThread()
• Delegate ApiProxyLocalImpl
ApiProxy#setDelegate()

Environment
•
• ApplicationID, versionID,
• Web SingleThread
•
ApiProxy#setEnvironmentForCurrentThread()

Delegate : ApiProxyLocalImpl
• Delegate
Delegate
•
• WEB-INF/queue.xml
datastore-indexes.xml

Delegate
•
Delegate
• … /
• ApiProxy#getDelegate()
AOP

Delegate
class MyDelegate implements Delegate {
Delegate original = ApiProxy.getDelegate();
public byte[] makeSyncCall(
Environment environment,
String service, String method,
byte[] request) throws ApiProxyException {
System.out.println(service+”:”+method);
return original.makeSyncCall(
environment, service, method, requst);
}
}

makeSyncCall()
byte[] Delegate#makeSyncCall(
Environment environment,
String service,
String method,
byte[] request)
throws ApiProxyException

makeSyncCall()
byte[] Delegate#makeSyncCall(
Environment environment,
String service,
String method,
byte[] request)
throws ApiProxyException

makeSyncCall()
• datastore_v3#GET
• : DatastorePb.GetRequest
• new GetRequest().mergeFrom(byte[])
• GetRequest#keyIterator() Key
Iterator
• : DatastorePb.GetResponse
• new GetResponse().mergeFrom(byte[])
• GetResponse#entityIterator()
Entity Iterator

• Mail
• MailService
Delegate#makeSyncCall() Stub
• makeSyncCall() byte[]
MailServicePb.MailMessage
MailMessage#getCC()...
assert

…

• …
• datastore_v3#GET
• memcache#GET datastore
mamcache#GET
• datastore_v3#PUT/DELETE
• memcache#DELETE datastore

shin1ogawa@