I was wondering if it is possible to get a specific file in a ZIP from Azure File Storage without downloading and unzipping the whole ZIP.
The problem is that the zip file can be large (>1 gb), while the file in the zip which I need is just a few MB tops.
If it is possible, could you provide an example or link(s)?
Thank you
I was wondering if it is possible to get a specific file in a ZIP from
Azure File Storage without downloading and unzipping the whole ZIP.
No. You would need to download the entire file from storage, unzip the file and then extract the desired file. It is possible to keep the entire downloaded file in memory (in form of stream) and have a zipping library work on that stream instead of saving the entire file on the disk. But you have to read the entire file.
Related
I've found tons of information about how to create and upload a zip file to Azure storage, but I'm trying to see if there's a good way to add content to an existing zip file in blob storage that doesn't involve downloading the whole blob, rebuilding in memory, then uploading again.
My use case involves zipping several hundred, up to several million, items into an archive to be stored in Azure blob storage for later download. I have code that will handle splitting so I don't wind up with a single several-GB size file, but I still run into memory management issues when dealing with large quantities of files. I'm trying to address this by creating the zip file in blob storage, and adding subsequent files to it one by one. I recognize this will incur cost for the additional writes, and that's fine.
I know how to use Append Blobs and Block Blobs, and I have working code to create the zip file and upload, but I can't seem to find out if there's a way to do this. Anyone managed to accomplish this, or able to confirm that this is not possible?
Since you're dealing with zip files, only way to add new files to an existing zip file is to download the blob, add new file to that zip file and then reupload that blob.
I want to download a single file in a remote Zip file that is in the cloud. The zip file is too large for me to download as a whole therefore I have decided to look for a way to download only a single file(XML) that I need within the archive. I have tried and Tested a webclient and web request but it downloads the whole zip file(also too large file for these technuques usually fails). I'm eyeing the SharpZipLib but I dont know how to use it. Is it the right library I should use or there are other available ones I can get and test. Thank you so much.
Suppose, I have a list of MP3 files on my server. And I want a user to download multiple files (which he wants through any means). For, this what i want is to create the zip file dynamically and while saving it into the Output Stream using the dotnetzip or ioniczip libraries.
Well, that's not the perfect solution if the zip file got heavy in size. As, in that scenario the server doesn't support resumable downloads. So, to overcome this approach, I need to handle the zip file structure internally and provide the resume support.
So, is there any library (open source) which i can use to provide resumable dyanamic zip files stream directly to the Output Stream. Or, if possible I will be happy if someone let me know the structure of zip file specially the header content + data content.
Once a download has started, you should not alter the ZIP file anymore. Because then a resume will just result in a broken ZIP file. So make sure your dynamically created ZIP file stays available!
The issue of providing resume-functionality was solved in this article for .NET 1.1, and it is still valid and functional.
In my Windows Azure code I want to download a ZIP file from Blob Storage and unzip it on the fly and store the unzipped contents to the disk. This way I save on first writing the file to the disk and then reading it when doing the extraction.
I'm trying to use DotNetZip for that.
The ZIP file is originally very big, so it is cut into pieces (not multipart archive, but a plain ZIP archive, just cut into smaller files) and each piece is uploaded into Blob Storage. I know how to iterate through all the parts and open each blob when neededn
Azure SDK has CloudBlob.OpenRead() that returns a Stream descendant.
DotNetZip has ZipInputStream class that has a constructor accepting a Stream.
How do I connect these pieces together so that I can download the ZIP file pieces one by one and get them extracted on the fly?
Create your own stream class that will return data from the corresponding CloudBlob according to its position.
Then use this class a input stream for your ZipInputStream.
public sealed class ZipBlobStream : Stream
{
...
http://msdn.microsoft.com/library/system.io.stream.aspx
I have a rar archive, I shake it to the ftp folder to be stored in the folder files.
How do I unzip the archive, that archive would not be seen in the system?
that would not have been possible to users of its intercept.
archive - the secret information, I can not open whatever it could to keep
Load into memory file content and decrypt in memory then you can traverse content without saving this secret data on hard disk or other I/O device.