[gdal-dev] Write overviews directly to S3

[Jeremy Palmer]

Hi Even,

On 18/05/2017, at 9:12 PM, Even Rouault <even.rouault at spatialys.com<mailto:even.rouault at spatialys.com>> wrote:
>
> Is is possible to directly write external overview to a S3 bucket? With GDAL
> 2.1.2 I get an error reporting that seek is not supported when writing to
> vsis3:



No, /vsis3/ only supports sequential writing in files (the original use case was to generate and upload a huge CSV file on the fly). I don't have all the details in mind but random writing might not be possible given the S3 API constraints, at least with the multipart upload API which is used currently.

OK thanks for clarifying the situation.




And another constraint of the current implementation is that a /vsis3/ file is either read-only or write-only, but not a mix of both, which would be needed for gdaladdo internal overviews. Perhaps external overview would work, but I'm not completely sure as creating a TIFF file might require seeking.



Perhaps a fully fledged read-write-update file system would be possible, but that wasn't in my initial design constraints.

For now we will work around the issue.

Thank for your help.

Cheers,
Jeremy


________________________________
This message contains information, which may be in confidence and may be subject to legal privilege. If you are not the intended recipient, you must not peruse, use, disseminate, distribute or copy this message. If you have received this message in error, please notify us immediately (Phone 0800 665 463 or info at linz.govt.nz) and destroy the original message. LINZ accepts no responsibility for changes to this email, or for any attachments, after its transmission from LINZ. Thank You.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20170518/e16deef3/attachment.html>