How to lazily add custom readers?

[brucelaughlin]

I have modified the ROMS native reader to read some biological variables. I have ROMS data coming from multiple files in multiple directories, and I would like to add multiple lazy readers to my model, so that readers are only initialized when the simulation reaches a given time.

In the documentation, it says that "add_readers_from_list" or "add_readers_from_file" are lazy by default, but I can't find any documentation about how to make a custom reader lazy before adding it. I tried using "r.is_lazy = True" (which is a property I saw somewhere; can't find the file at this moment) before adding the reader "r", but my code seems to still be initializing all readers before beginning the simulation.

So, how can I make custom readers lazy, specifically a reader modeled after "reader_ROMS_native" ? Must it be done within the reader code itself, or can a property be modified before adding it?

I'll continue reading, including looking at the code of "reader_lazy.py" to see if I can further modify my own reader to make it work as a lazy reader.

Thanks!

[knutfrode]

I believe you can do

>>> from opendrift.readers.reader_lazy import Reader
>>> r = Reader(<file or URL>)