Problem with firebase admin database collections method in python

[Juan Antonio Fernández Sánchez]

I used to use this code to get a copy of Firestore database to local, but the last day I find this error suddenly:

google.api_core.exceptions.InvalidArgument: 400 Document parent name "projects/some-niceproject/databases/(default)" lacks "/" at index 43.

This is a summary of it:

grpc._channel._Rendezvous: <_Rendezvous of RPC that terminated with: status = StatusCode.INVALID_ARGUMENT details = "Document parent name "projects/some-niceproject/databases/(default)" lacks "/" at index 43." debug_error_string = "{"created":"@1560895696.899080325","description":"Error received from peer ipv4:172.217.17.10:443","file":"src/core/lib/surface/call.cc","file_line":1046,"grpc_message":"Document parent name "projects/some-niceproject/databases/(default)" lacks "/" at index 43.","grpc_status":3}"

So, my normal way to proceed is, initialize the app, and instanciate the firestore client :

default_app = firebase_admin.initialize_app( credential=cred ) 
firestore_db = firestore.client()

No problem for now, isn't the first time that I do that, but when I do list(collections) the problem appear.

As I think that the problem is that only lack '/' at the end of database path I have been trying to set it, some like this:

print(firestore_db._rpc_metadata_internal) 
[('google-cloud-resource-prefix', 'projects/some-niceproject/databases/(default)')] 
firestore_db._rpc_metadata_internal = [('google-cloud-resource-prefix', 'projects/some-niceproject/databases/(default)/')] 
print(firestore_db._rpc_metadata_internal) 
[('google-cloud-resource-prefix', 'projects/some-niceproject/databases/(default)')]

But without results.

The worst part is that if I set the name of some collection I can access to the documents without problem.

I have tried to downgrade grpcio to older versions (now in 1.21.1) and the same with firebase_admin, without any results.

I can continue the work telling exactly the name of each collection but I would like it not will be necessary because I am working in a package to do more easy the copy of firebase databases.

Any idea about the reason of this new error? Thank you so much!

This question is also in StackOverflow here.