commands: make 'wallet'-mangling in decorator less obscure, and fixes

- some commands expect a 'wallet_path' arg, while others expect 'wallet'
- 'wallet_path' in the end is supposed to be a str,
  'wallet' in the end is supposed to be an Optional[Abstract_Wallet]
- initially, in the decorator, 'wallet' can be a str, in which case
  the decorator replaces it with an Abstract_Wallet (from the daemon)
- Previously the decorator sometimes converted 'wallet_path' to 'wallet'.
  This was because when called from the CLI it was always given 'wallet_path' (and never 'wallet),
  while when called from JSON-RPC it was given either 'wallet' or 'wallet_path' (depending on command).
  Now, the CLI also behaves as JSON-RPC, and hence 'wallet_path' and 'wallet' are fully separate.
- A bug is fixed where, when a command that only optionally takes a 'wallet' (such as gettransaction),
  was called from the JSON-RPC with the arg present, it raised; and when called from CLI with the arg present
  the arg was not actually passed to the command.
- A bug is fixed where if one command calls another command (that both take a 'wallet'),
  it would raise (due to assuming 'wallet' is str and needs to be converted to Abstract_Wallet).
  This fixes #6154.

-----

$ ./run_electrum --testnet daemon -d
$ ./run_electrum --testnet load_wallet -w ~/.electrum/testnet/wallets/default_wallet

$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"gettransaction","params":{"txid":"9f43ff71ea2594873e4e7d15e61254a3661ff2df1af76325c854d9aa199550ce"}}' http://user:pass@127.0.0.1:7777
{"jsonrpc": "2.0", "result": "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", "id": "curltext"}

$ curl --data-binary '{"id":"curltext","jsonrpc":"2.0","method":"gettransaction","params":{"txid":"9f43ff71ea2594873e4e7d15e61254a3661ff2df1af76325c854d9aa199550ce", "wallet":"~/.electrum/testnet/wallets/default_wallet"}}' http://user:pass@127.0.0.1:7777
{"jsonrpc": "2.0", "error": {"code": -32000, "message": "'str' object has no attribute 'db'"}, "id": "curltext"}

electrum/commands.py

@@ -106,6 +106,16 @@ class Command:
             self.options = []
             self.defaults = []
 
+        # sanity checks
+        if self.requires_password:
+            assert self.requires_wallet
+        for varname in ('wallet_path', 'wallet'):
+            if varname in varnames:
+                assert varname in self.options
+        assert not ('wallet_path' in varnames and 'wallet' in varnames)
+        if self.requires_wallet:
+            assert 'wallet' in varnames
+
 
 def command(s):
     def decorator(func):
@@ -119,18 +129,20 @@ def command(s):
             password = kwargs.get('password')
             daemon = cmd_runner.daemon
             if daemon:
-                if (cmd.requires_wallet or 'wallet_path' in cmd.options) and kwargs.get('wallet_path') is None:
-                    # using JSON-RPC, sometimes the "wallet" kwarg needs to be used to specify a wallet
-                    kwargs['wallet_path'] = kwargs.pop('wallet', None) or daemon.config.get_wallet_path()
-                if cmd.requires_wallet:
-                    wallet_path = kwargs.pop('wallet_path')
+                if 'wallet_path' in cmd.options and kwargs.get('wallet_path') is None:
+                    kwargs['wallet_path'] = daemon.config.get_wallet_path()
+                if cmd.requires_wallet and kwargs.get('wallet') is None:
+                    kwargs['wallet'] = daemon.config.get_wallet_path()
+                if 'wallet' in cmd.options:
+                    wallet_path = kwargs.get('wallet', None)
+                    if isinstance(wallet_path, str):
                         wallet = daemon.get_wallet(wallet_path)
                         if wallet is None:
                             raise Exception('wallet not loaded')
                         kwargs['wallet'] = wallet
-            else:
-                # we are offline. the wallet must have been passed if required
-                wallet = kwargs.get('wallet')
+            wallet = kwargs.get('wallet')  # type: Optional[Abstract_Wallet]
+            if cmd.requires_wallet and not wallet:
+                raise Exception('wallet not loaded')
             if cmd.requires_password and password is None and wallet.has_password():
                 raise Exception('Password required')
             return await func(*args, **kwargs)

electrum/daemon.py

@@ -251,8 +251,10 @@ class CommandsServer(AuthenticatedServer):
         kwargs = {}
         for x in cmd.options:
             kwargs[x] = config_options.get(x)
-        if cmd.requires_wallet:
+        if 'wallet_path' in cmd.options:
             kwargs['wallet_path'] = config_options.get('wallet_path')
+        elif 'wallet' in cmd.options:
+            kwargs['wallet'] = config_options.get('wallet_path')
         func = getattr(self.cmd_runner, cmd.name)
         # fixme: not sure how to retrieve message in jsonrpcclient
         try:
@@ -477,7 +479,7 @@ class Daemon(Logger):
         path = standardize_path(path)
         self._wallets[path] = wallet
 
-    def get_wallet(self, path: str) -> Abstract_Wallet:
+    def get_wallet(self, path: str) -> Optional[Abstract_Wallet]:
         path = standardize_path(path)
         return self._wallets.get(path)