Possible Issue with adios2 v.2.9.1 python module

[PhysicsDan]

Hello,

Describe the bug
Unable to read data from adios2 file produced from WarpX PIC code when using 2.9.1

To Reproduce

1. Data is produced via WarpX pic code which uses adios2 v2.9.1 to store the data. Adios2 is installed via conda forge.
2. Using bpls I can see the data is correctly written to the file.
3. Using the available_variables function from adios2 python module returns an empty list (Note: Previously worked in v. 2.8.3)

import adios2

fp = adios2.open("myfile.py", "r")
print(fp.available_variables())

Note: openpmd-api also correctly can see the contents of the file.

Expected behavior
I should see the same variables that are displayed when running bpls

Desktop (please complete the following information):

• OS/Platform: CentOS
• Build adios2 nompi_py311hc31d2c9_102

Additional context

Thanks

Following up

[anagainaru]

Hey Dan, adios 2.9 is when BP5 became the default engine. For BP5 you have to inspect variables within steps, you can no longer do this before BeginStep. Could you trying modifying your code and see if it works?

[PhysicsDan]

Hi Ana,
Apologies for the late reply! Yes thanks I had missed that change - all working now.
Thanks for the help