The document discusses code for making synchronous API calls in AppEngine. It defines a default delegate for API calls and overrides the makeSyncCall method to throw an exception for certain datastore Put calls. The code gets the service and method from HTTP request headers and writes the response bytes to the output stream. It also references a protocolBufferOnHttp method for making API calls over HTTP.

1. appengine ja
night
sapporo#1
AppEngine Lower
shin1ogawa@

4. Delegate

5. final ApiProxy.Delegate defaultDelegate =
ApiProxy.getDelegate();
public byte[] makeSyncCall(
Environment environment, String service,
String method, byte[] request)
throws ApiProxyException {
System.out.println(service + “#” + method);
defaultDelegate.makeSyncCall(
serviceName, methodName, request);
}

7. public byte[] makeSyncCall(
Environment environment, String service,
String method, byte[] request)
throws ApiProxyException {
if (service.equals(“datastore_v3”)
&& method.equalsIgnoreCase(“Put”)
){
throw new CapabilityDisabledException();
}
defaultDelegate.makeSyncCall(
serviceName, methodName, request);
}

11. String service =
req.getHeader(SERVICE_NAME);
String method = req.getHeader(METHOD_NAME);
byte[] requestBytes =
IOUtils.toByteArray(req.getInputStream());
byte[] responseBytes =
ApiProxy.getDelegate().makeSyncCall(
ApiProxy.getCurrentEnvironment(),
service, method, requestBytes);
resp.getOutputStream().write(responseBytes);

12. public byte[] makeSyncCall(
Environment environment, String service,
String method, byte[] request)
throws ApiProxyException {
return protocolBufferOnHttp(
environment, service, method, request);
}
byte[] protocolBufferOnHttp(.....) {
// makeSyncCallServlet Post
// byte[]
}

14. shin1ogawa@