Snappy SliceAssembly java.lang.NullPointerException

Has someone managed to run SliceAssembly in Snappy?

I can’t get it to work no matter what I do, and the NullPointerException error is too generic for me to debug.

Currently I am trying to run slice assembly and then apply-orbit. I don’t have enough local memory to test the scenes on my local PC and I have not been able to apply the command line GPT SliceAssembly graph either to error check.

product_list - []
products = snappy.jpy.array(‘org.esa.snap.core.datamodel.Product’, len(product_list))
for count in range(len(product_list)):
products[count] = snappy.ProductIO.readProduct(str(product_list[count]))
parameters = HashMap()
parameters.put(“selectedPolarisations”, “VV”)
result_SA = snappy.GPF.createProduct(“SliceAssembly”, parameters, products)

If anyone has working code I would love a snippet showing which hashmap parameters you provide and how you input two (or more) scenes. In my code I only use the parameter selectedPolarisation and use the jpy.array snap.core.datamodel method to input two products that after they are read by

Are you using the latest updates? There were fixes to slice assembly to support the product format changes.

I am actually not sure. I am using _unix_6_0 but I am not sure if it includes the latest changes. I see my GUI is 6.0.6.

I pull my image from dockerhub mmoor/snap-with-python
Which pulls the snap debian base image from:
Which downloads v 6_0 from

Would this version have the recent changes or should I build the image from scratch or something?

After getting the installer and installing SNAP, you need to update the modules to get the latest changes.

snap --modules --update-all --nosplash
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Great this has fixed this and slice assembly is working, thank you.
Now to see what it broke :slight_smile: