# Access serverside VTK Object with Python

**URL:** https://discourse.paraview.org/t/access-serverside-vtk-object-with-python/8831
**Category:** ParaView Support
**Created:** [January 24, 2022, 11:02am UTC](https://discourse.paraview.org/t/access-serverside-vtk-object-with-python/8831 "2022-01-24T11:02:18Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Azrael3000](https://discourse.paraview.org/user_avatar/discourse.paraview.org/azrael3000/32/7648_2.png) [@Azrael3000](https://discourse.paraview.org/u/Azrael3000)
#### Post date: [January 24, 2022, 11:02am UTC](https://discourse.paraview.org/t/access-serverside-vtk-object-with-python/8831/1 "2022-01-24T11:02:18Z")

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Hi have a macro that I use to visualize my data with. What I do is take all sources, check whether they are vtkPVDReader and then analyze the data that was read by that reader. On client side this is simply done using

```auto
mb_source = source.SMProxy.GetClientSideObject().GetOutputDataObject(0)

```

where `source` is one of the vtkPVDReader sources and `mb_source` is just a `vtkMultiBlockDataSet` that I can then work with.

Now when using ParaView in client/server mode this no longer works as, without surprise, `GetClientSideObject` returns `None`. I did not manage to find a way to access the multiblock data on the server, so if anybody knows how to do that please let me know.

What I did try so far is to use `source.SMProxy.GetOutputPort(0)` and `.GetClassName()` reports `vtkMultiBlockDataSet` I can’t seem to figure out how to actually access the data.

Thanks in advance for your help,  
Arno

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### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 24, 2022, 12:12pm UTC](https://discourse.paraview.org/t/access-serverside-vtk-object-with-python/8831/2 "2022-01-24T12:12:09Z")

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servermanager.Fetch:[servermanager Module — ParaView/Python 5.9.1 documentation](https://kitware.github.io/paraview-docs/latest/python/paraview.servermanager.html#paraview.servermanager.Fetch)

TBH you should avoid doing that, it is a costly call with big datasets.

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### Author: ![Azrael3000](https://discourse.paraview.org/user_avatar/discourse.paraview.org/azrael3000/32/7648_2.png) [@Azrael3000](https://discourse.paraview.org/u/Azrael3000)
#### Post date: [January 25, 2022, 7:28am UTC](https://discourse.paraview.org/t/access-serverside-vtk-object-with-python/8831/3 "2022-01-25T07:28:11Z")

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Thanks Mathieu, I see what that does and I actually think I can get around it as I only really need the metadata at this point. I have a follow up question regarding that but I will be posting it in a new thread as it might be interesting as standalone question.