Check the number of already registered tokens when createERC20TokenNetwork fails

[pirapira]

When TokenNetworkRegistryProxy tries to call createERC20TokenNetwork() and the call fails because the TokenNetworkRegistry contract already has too many TokenNetworks registered, the code seems to raise a RaidenUnrecoverableError with not much information.

The correct approach is to raise a more specific error:

raiden/raiden/network/proxies/token_network_registry.py

Line 188 in ee3336d

[pirapira]

I think "too many tokens already registered" is a recoverable error.

• which exception shall we raise here?
• where should this exception be handled?

[pirapira]

Perhaps the situation is very similar to that of AlreadyRegisteredTokenAddress.

[pirapira]

Do I need to add an extra check in api/python.py? Perhaps yes.

[pirapira]

I'm trying to understand what to raise where.

[pirapira]

Why does python.py rename an exception RaidenUnrecoverableException into AlreadyRegisteredTokenAddress here?

raiden/raiden/api/python.py

Line 236 in d51edc3

if "Token already registered" in str(e):

Why doesn’t the proxy raise AlreadyRegisteredTokenAddress?