google-cloud-datastore

问题 I want to do something like the Expando Model that python supports on app engine. Sometimes you don't want to declare your properties ahead of time. A special model subclass, Expando, changes the behavior of its entities so that any attribute assigned (as long as it doesn't start with an underscore) is saved to the Datastore. How can I do this in Go? 回答1: Note beforehand: There are 2 APIs. The one with import path appengine/datastore uses channels as arguments. The other with import path

问题 I've looked everywhere and wasted a lot of time on something that I think is probably very simple. Thanks for the help in advance. I have a google app engine app using the cloud datastore written in Java. I have an entity class as follows: @Entity public class Student { @Id private Long studentId; @Index private League league; @Index private String year; private String firstName; private String lastName; ... } I have a csv file of 1K students. I need to upload this info into the cloud

问题 I've looked everywhere and wasted a lot of time on something that I think is probably very simple. Thanks for the help in advance. I have a google app engine app using the cloud datastore written in Java. I have an entity class as follows: @Entity public class Student { @Id private Long studentId; @Index private League league; @Index private String year; private String firstName; private String lastName; ... } I have a csv file of 1K students. I need to upload this info into the cloud

问题 I have stored pdf files uploaded by users in the Datastore, as BlobProperties: <form action="/" method="post" enctype="multipart/form-data"> <input type="file" name="pdf"> <input type="submit" value="Upload"> </form> with the following handler: def post(self): p = self.request.get('pdf') if p: person.pdf = p I have also tried this version of the last line: person.pdf = db.Blob(p) which seems to work the same way. I try to display it thus: <embed src="{{ person.pdf }}" width="500" height="375"

问题 I've been trying to get JDO working with parent/child relationships, but I'm not having much success. Using the relationship setup as seen here and queries as seen here, I want to be able to link a child to a parent, then be able to query for all children of a given parent. Unfortunately, I don't seem to be querying the children correctly. I keep getting the error: Class Parent for query has not been resolved. Check the query and any imports/aliases specification Here's what my code looks

问题 This is the model: class Rep(db.Model): author = db.UserProperty() replist = db.ListProperty(str) unique = db.ListProperty(str) date = db.DateTimeProperty(auto_now_add=True) I am writing replist to datastore: L = [] rep = Rep() s = self.request.get('sentence') L.append(s) rep.replist = L rep.put() and retrieve mylist = rep.all().fetch(1) I assume that mylist is a list. How do I print its elements? When I try it I end up with the object; something like [<__main__.Rep object at 0x04593C30>]

问题 Hello iam new to GWT framework. I want to persist my domain objects/entities to google application engine datastore using rpc. A simple implementation to test if i can make multiple rpc calls ( greetServer() , saveStudent() ) Student import javax.jdo.annotations.Extension; import javax.jdo.annotations.IdGeneratorStrategy; import javax.jdo.annotations.PersistenceCapable; import javax.jdo.annotations.Persistent; import javax.jdo.annotations.PrimaryKey; import com.google.gwt.user.client.rpc

问题 I am trying to sort a list of items by my property 'price' but I'm getting error. This is my filter items = ofy().load().type(MyItem.class) .filter("OtherEntityRef", tmpEntity) .order("price").limit(100) .list(); But we I run it, the log shows the erro: Uncaught exception from servlet java.io.IOException: com.google.appengine.repackaged.org.codehaus.jackson.map.JsonMappingException: no matching index found. The suggested index for this query is: <datastore-index kind="MyClass" ancestor="false

问题 What I'm doing is creating a transaction where 1) An entity A has a counter updated to +1 2) A new entity B is written to the datastore. It looks like this: WrappedBoolean result = ofy().transact(new Work<WrappedBoolean>() { @Override public WrappedBoolean run() { // Increment count of EntityA.numEntityBs by 1 and save it entityA.numEntityBs = entityA.numEntityBs +1; ofy().save().entity(entityA).now(); // Create a new EntityB and save it EntityB entityB = new EntityB(); ofy().save().entity

问题 What I'm doing is creating a transaction where 1) An entity A has a counter updated to +1 2) A new entity B is written to the datastore. It looks like this: WrappedBoolean result = ofy().transact(new Work<WrappedBoolean>() { @Override public WrappedBoolean run() { // Increment count of EntityA.numEntityBs by 1 and save it entityA.numEntityBs = entityA.numEntityBs +1; ofy().save().entity(entityA).now(); // Create a new EntityB and save it EntityB entityB = new EntityB(); ofy().save().entity