How can I delete a blob from the blobstore and its corresponding BlobKeyProperty from the datastore? I've implemented my solution as below, however, while the blob is successfully deleted from the blobstore, the BlobKeyProperty from the datastore is not cleared (ie: companyPerson.profile_pic_blobkey = SOME_RANDOM_STRING here instead of None).
The model file:
class CompanyPerson(ndb.Model):
profile_pic_blobkey = ndb.BlobKeyProperty()
Handler:
from google.appengine.ext.blobstore import BlobInfo
....
blob_info = BlobInfo.get(companyPerson.profile_pic_blobkey)
blob_info.delete()
Edit: Somewhat Solved:-
Well I've got it sorted out, though I don't know if it's the best way since most online references don't mention this step. But basically what I did was to insert
profile_pic_blobkey = None
right after blob_info.delete().
Related
I've been facing a very strange problem in Realm which doesn't occur every time , but it's been really annoying.
I'm saving a lot of information offline which come from a Webservice using realm. I don't get any exception while saving all these information.
Later I'm able to get all these objects by accessing them through MyObject.allObjects().
These objects contains a property which is an UUID, which I use to download the file related to this object and save it locally, after I finish downloading the file, I update my Realm Object with the path of the file, but some times when I do it:
let pred = NSPredicate(format: "UUID = %#", fileId)
print("This is the select \(pred.predicateFormat)")
let results = IssueFile.objects(with: pred) as! RLMResults<IssueFile>
The variable results is empty, but if I check Realm Database via Realm Browser, I can find the item I'm looking for.
So my question is: why some times Realm can't find the object I'm selecting? As I'm saving a lot of information, is there something I should change in the Realm Configuration?
I've already set the UUID as primary key of the table:
+ (NSString *)primaryKey {
return #"UUID";
}
Thanks,
I noticed this in the debug environment where I have to do many re-installs in order to test persistent data storage, initial settings, etc... It may not be relevant in production, but I mention this anyway just to inform other developers.
Any files created by an app in its App Folder are not 'visible' to queries after manual un-install / re-install (from IDE, for instance). The same applies to the 'Encoded DriveID' - it is no longer valid.
It is probably 'by design' but it effectively creates 'orphans' in the app folder until manually cleaned by 'drive.google.com > Manage Apps > [yourapp] > Options > Delete hidden app data'. It also creates problem if an app relies on finding of files by metadata, title, ... since these seem to be gone. As I said, not a production problem, but it can create some frustration during development.
Can any of friendly Googlers confirm this? Is there any other way to get to these files after re-install?
Try this approach:
Use requestSync() in onConnected() as:
#Override
public void onConnected(Bundle connectionHint) {
super.onConnected(connectionHint);
Drive.DriveApi.requestSync(getGoogleApiClient()).setResultCallback(syncCallback);
}
Then, in its callback, query the contents of the drive using:
final private ResultCallback<Status> syncCallback = new ResultCallback<Status>() {
#Override
public void onResult(#NonNull Status status) {
if (!status.isSuccess()) {
showMessage("Problem while retrieving results");
return;
}
query = new Query.Builder()
.addFilter(Filters.and(Filters.eq(SearchableField.TITLE, "title"),
Filters.eq(SearchableField.TRASHED, false)))
.build();
Drive.DriveApi.query(getGoogleApiClient(), query)
.setResultCallback(metadataCallback);
}
};
Then, in its callback, if found, retrieve the file using:
final private ResultCallback<DriveApi.MetadataBufferResult> metadataCallback =
new ResultCallback<DriveApi.MetadataBufferResult>() {
#SuppressLint("SetTextI18n")
#Override
public void onResult(#NonNull DriveApi.MetadataBufferResult result) {
if (!result.getStatus().isSuccess()) {
showMessage("Problem while retrieving results");
return;
}
MetadataBuffer mdb = result.getMetadataBuffer();
for (Metadata md : mdb) {
Date createdDate = md.getCreatedDate();
DriveId driveId = md.getDriveId();
}
readFromDrive(driveId);
}
};
Job done!
Hope that helps!
It looks like Google Play services has a problem. (https://stackoverflow.com/a/26541831/2228408)
For testing, you can do it by clearing Google Play services data (Settings > Apps > Google Play services > Manage Space > Clear all data).
Or, at this time, you need to implement it by using Drive SDK v2.
I think you are correct that it is by design.
By inspection I have concluded that until an app places data in the AppFolder folder, Drive does not sync down to the device however much to try and hassle it. Therefore it is impossible to check for the existence of AppFolder placed by another device, or a prior implementation. I'd assume that this was to try and create a consistent clean install.
I can see that there are a couple of strategies to work around this:
1) Place dummy data on AppFolder and then sync and recheck.
2) Accept that in the first instance there is the possibility of duplicates, as you cannot access the existing file by definition you will create a new copy, and use custom metadata to come up with a scheme to differentiate like-named files and choose which one you want to keep (essentially implement your conflict merge strategy across the two different files).
I've done the second, I have an update number to compare data from different devices and decide which version I want so decide whether to upload, download or leave alone. As my data is an SQLite DB I also have some code to only sync once updates have settled down and I deliberately consider people updating two devices at once foolish and the results are consistent but undefined as to which will win.
I'm attempting to cache data in a file for a Windows Store app, and using the DateCreated value to determine if it is out of date.
I first tried doing this:
var file = await rootFolder.CreateFileAsync(filename, Windows.Storage.CreationCollisionOption.ReplaceExisting);
FileIO.WriteTextAsync(file, contents);
but when it saves the file only the DateModified value is changed, even though the comments for the ReplaceExisting option clearly state that it recreates the file and replaces an existing one.
So I decided to force it to delete the file and recreate it with this:
var file = await rootFolder.CreateFileAsync(filename, Windows.Storage.CreationCollisionOption.ReplaceExisting);
// force delete because windows rt is not doing what it's supposed to in the line above!!
await file.DeleteAsync();
file = await rootFolder.CreateFileAsync(filename);
FileIO.WriteTextAsync(file, contents);
but amazingly, I still get the same result! The file is deleted and recreated with the OLD CREATION DATE!
Is this a bug, or am I doing something wrong here?
This is by design, a feature called "File system tunneling". This KB article explains the behavior and rationale.
The workaround it documents requires registry editing, clearly you cannot rely on that in a Store application. You'll need to find a workaround, like using the last-written timestamp or alternating between two files or keep track of age in a separate file.
Thanks for the comments everyone, it turns out the Modified date IS available but you have to get it through the GetBasicPropertiesAsync() method as shown here: http://msdn.microsoft.com/en-us/library/windows/apps/windows.storage.fileproperties.basicproperties.datemodified.aspx
I am using the Microsoft Azure .NET client libraries to interact with Azure cloud storage. I need to be able to access additional information about each blob in its metadata collection. I am currently using CloudBlobDirectory.ListBlobs() method to get a list of blobs in a particular directory of a directory structure I've devised in the blob names. The ListBlobs() method returns a list of IListBlobItem objects. They only have a couple of properties: Url and references to parent directory and parent container. I need to get to the metadata of the actual blob objects.
I envisioned there would be a way to either cast the IListBlobItem to a BlockBlob object or use the IListBlockItem to get a reference to the BlockBlob, but can't seem to find a way to do that.
My question is: Is there a way to get a BlockBlob object from this method, or do I have to use a different way of getting the actual BlockBlob objects? If different, then can you suggest a way to achieve this, while also being able to filter by the "directory" scheme?
OK... I found a way to do this, and while it seems a little clunky and indirect, it does achieve the main thing I thought should be doable, which is to cast the IListBlobItem directly to a CloudBlockBlob object.
What I am doing is getting the list from the Directory object's ListBlobs() method and then looping over each item in the list and casting the item to a CloudBlockBlob object and then calling the FetchAttributes() method to retrieve the properties (including the metadata). Then add a new "info" object to a new list of info objects. Here's the code I'm using:
CloudBlobDirectory dir = container.GetDirectoryReference(dirPath);
var blobs = dir.ListBlobs(true);
foreach (IListBlobItem item in blobs)
{
CloudBlockBlob blob = (CloudBlockBlob)item;
blob.FetchAttributes();
files.Add(new ImageInfo
{
FileUrl = item.Uri.ToString(),
FileName = item.Uri.PathAndQuery.Replace(restaurantId.ToString().PadLeft(3, '0') + "/", ""),
ImageName = blob.Metadata["Name"]
});
}
The whole "Blob" concept seems needlessly complex and doesn't seem to achieve what I'd have thought would have been one of the main features of the Blob wrapper. That is, a way to expand search capabilities by allowing a query over name, directory, container and metadata. I'd have thought you could construct a linq query that would read somewhat like: "return a list of all blobs in the 'images' container, that are in the 'natural/landscapes/' directory path that have a metadata key of 'category' with the value of 'sunset'". There doesn't seem to be a way to do that and that seems to be a missed opportunity to me. Oh, well.
If I'm wrong and way off base here, please let me know.
This approach has been developed for Java, but I hope it can somehow be modified to fit any other supported language. Despite the functionality you ask has not been explicitly developed yet, I think I found a different (hopefully less clunky) way to access CloudBlockBlob data from a ListBlobItem element.
The following code can be used to delete, for example, every blob inside a specific directory.
String blobUri;
CloudBlobClient blobClient = /* Obtain your blob client */
try{
CloudBlobContainer container = /* Obtain your blob container */
for (ListBlobItem blobItem : container.listBlobs(blobPrefix)) {
if (blobItem instanceof CloudBlob) {
blob = (CloudBlob) blobItem;
if (blob.exists()){
System.out.println("Deleting blob " + blob.getName());
blob.delete();
}
}
}
}catch (URISyntaxException | StorageException ex){
Logger.getLogger(BlobOperations.class.getName()).log(Level.SEVERE, null, ex);
}
The previous answers are good. I just wanted to point out 2 things:
1) Nowadays ASYNC programming is recommended to do and supported by Azure SDK as well. So try to use it:
CloudBlobDirectory dir = container.GetDirectoryReference(dirPath);
var blobs = dir.ListBlobs(true);
foreach (IListBlobItem item in blobs)
{
CloudBlockBlob blob = (CloudBlockBlob)item;
await blob.FetchAttributesAsync(); //Use async calls...
}
2) Fetching Metadata in a separate call is not efficient. The code makes 2 HTTP request per blob object. ListBlobs() method supports getting Metadata with as well in one call by setting BlobListingDetails parameter:
CloudBlobDirectory dir = container.GetDirectoryReference(dirPath);
var blobs = dir.ListBlobs(useFlatBlobListing: true, blobListingDetails: BlobListingDetails.Metadata);
I recommend to use second code it it is possible. Since it is the most efficient way to fetch Metadata.
I have a completely empty RavenHQ database that's linked to my Appharbor application. The amount of space the database is currently using is 1.1mb out of an available 25mb for my bronze account. The database previously had records in it, but I have deleted them using "delete collection" in the management studio.
The very first time I call session.Store(myobject), and BEFORE I call .SaveChanges(), I get the following error.
System.InvalidOperationException: Url: "/docs/Raven/Hilo/AccItems"
Raven.Database.Exceptions.OperationVetoedException: PUT vetoed by Raven.Bundles.Quotas.Triggers.DatabaseSizeQoutaForDocumetsPutTrigger because: Database size is 45,347 KB, which is over the allowed quota of 25,600 KB. No more documents are allowed in.
Now, the document is definitely not that big, so I don't know what this error can mean, especially as I don't think I've even hit the database at that point since I haven't closed the session by calling SaveChanges(). Any ideas? Here's the code itself.
XDocument doc = XDocument.Parse(rawXml);
var accItems = ExtractItemsFromFeed(doc);
using (IDocumentSession session = _store.OpenSession())
{
var dbItems = session.Query<AccItem>().ToList();
foreach (var item in accItems)
{
var existingRecord = dbItems.SingleOrDefault(x => x.Source == x.SourceId == cottage.SourceId);
if (existingRecord == null)
{
session.Store(item);
_logger.Info("Saved new item {0}.", item.ShortName);
}
else
{
existingRecord.ShortName = item.ShortName;
_logger.Info("Updated item {0}.", item.ShortName);
}
session.SaveChanges();
}
}
Any other comments about the style of this code would be most welcome, as I was unsure of the best way to approach the "update existing item or create if it isn't there" scenario.
The answer here was as follows.
RavenHQ support found that the database was indeed oversized, but it seemed that the size reported in the Appharbor-branded RavenHQ control panel was incorrect. I had filled up the database way over the limit with a previous faulty version of the code posted above, so the error message I received was actually correct.
Fixing this problem without paying to upgrade the database wasn't straightforward, as it's not possible to shrink the database. As I also wasn't able to delete my single Appharbor/RavenHQ database or create another one that left me with the choice of creating an entirely new Appharbor application, or registering directly with RavenHQ for a new account. I chose the latter. The RavenHQ-branded control panel is slightly different to the Appharbor one, in that it has the ability to create and delete databases.
So to summarize: there doesn't seem to be any benefit to using RavenHQ as an add-on to Appharbor - you might as well go and get a proper free RavenHQ account.