When importing a plugin, if it raised an exception in its `__init__` file, we
ignored it, and still loaded the plugin, in a potentially half-broken state.
This is because maybe_load_plugin_init_method only calls exec_module_from_spec
if the plugin is not already in sys.modules, but exec_module_from_spec
will put the plugin into sys.modules even if it errors.
Consider this patch to test with, enable the "labels" plugin:
```patch
diff --git a/electrum/plugins/labels/__init__.py b/electrum/plugins/labels/__init__.py
index b68127df8e..0d6d95abce 100644
--- a/electrum/plugins/labels/__init__.py
+++ b/electrum/plugins/labels/__init__.py
@@ -21,3 +21,5 @@ async def pull(self: 'Commands', plugin: 'LabelsPlugin' = None, wallet=None, for
arg:bool:force:pull all labels
"""
return await plugin.pull_thread(wallet, force=force)
+
+raise Exception("heyheyhey")
```
I would expect we don't load the labels plugin due to the error, but we do:
```
>>> plugins.get_plugin("labels")
<electrum.plugins.labels.qt.Plugin object at 0x7801df30fb50>
```
Log:
```
$ ./run_electrum -v --testnet -o
0.75 | I | simple_config.SimpleConfig | electrum directory /home/user/.electrum/testnet
0.75 | E | p/plugin.Plugins | cannot initialize plugin labels: Error pre-loading electrum.plugins.labels: Exception('heyheyhey')
Traceback (most recent call last):
File "/home/user/wspace/electrum/electrum/plugin.py", line 148, in exec_module_from_spec
spec.loader.exec_module(module)
File "<frozen importlib._bootstrap_external>", line 883, in exec_module
File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
File "/home/user/wspace/electrum/electrum/plugins/labels/__init__.py", line 25, in <module>
raise Exception("heyheyhey")
Exception: heyheyhey
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/home/user/wspace/electrum/electrum/plugin.py", line 167, in load_plugins
self.maybe_load_plugin_init_method(name)
File "/home/user/wspace/electrum/electrum/plugin.py", line 293, in maybe_load_plugin_init_method
module = self.exec_module_from_spec(init_spec, base_name)
File "/home/user/wspace/electrum/electrum/plugin.py", line 150, in exec_module_from_spec
raise Exception(f"Error pre-loading {path}: {repr(e)}") from e
Exception: Error pre-loading electrum.plugins.labels: Exception('heyheyhey')
0.75 | D | util.profiler | Plugins.__init__ 0.0030 sec
0.84 | I | simple_config.SimpleConfig | electrum directory /home/user/.electrum/testnet
0.89 | I | __main__ | get_default_language: detected default as lang='en_UK'
0.89 | I | i18n | setting language to 'en_UK'
0.89 | I | logging | Electrum version: 4.5.8 - https://electrum.org - https://github.com/spesmilo/electrum
0.89 | I | logging | Python version: 3.10.12 (main, Feb 4 2025, 14:57:36) [GCC 11.4.0]. On platform: Linux-6.8.0-52-generic-x86_64-with-glibc2.35
0.89 | I | logging | Logging to file: /home/user/.electrum/testnet/logs/electrum_log_20250319T161247Z_6605.log
0.89 | I | logging | Log filters: verbosity '*', verbosity_shortcuts ''
0.89 | I | exchange_rate.FxThread | using exchange CoinGecko
0.90 | D | util.profiler | Daemon.__init__ 0.0047 sec
0.90 | I | daemon.Daemon | starting taskgroup.
0.90 | I | daemon.CommandsServer | now running and listening. socktype=unix, addr=/home/user/.electrum/testnet/daemon_rpc_socket
0.90 | I | p/plugin.Plugins | registering hardware bitbox02: ['hardware', 'bitbox02', 'BitBox02']
0.90 | I | p/plugin.Plugins | registering hardware coldcard: ['hardware', 'coldcard', 'Coldcard Wallet']
0.90 | I | p/plugin.Plugins | registering hardware digitalbitbox: ['hardware', 'digitalbitbox', 'Digital Bitbox wallet']
0.90 | I | p/plugin.Plugins | could not find manifest.json of plugin hw_wallet, skipping...
0.90 | I | p/plugin.Plugins | registering hardware jade: ['hardware', 'jade', 'Jade wallet']
0.90 | I | p/plugin.Plugins | registering hardware keepkey: ['hardware', 'keepkey', 'KeepKey wallet']
0.90 | I | p/plugin.Plugins | registering hardware ledger: ['hardware', 'ledger', 'Ledger wallet']
0.90 | I | p/plugin.Plugins | registering hardware safe_t: ['hardware', 'safe_t', 'Safe-T mini wallet']
0.90 | I | p/plugin.Plugins | registering hardware trezor: ['hardware', 'trezor', 'Trezor wallet']
0.90 | I | p/plugin.Plugins | registering wallet type ('2fa', 'trustedcoin')
1.01 | I | p/plugin.Plugins | loaded plugin 'labels'. (from thread: 'GUI')
1.01 | D | util.profiler | Plugins.__init__ 0.1183 sec
```
This allows plugins to document the commands they add.
The docstring is parsed as a regular expression:
arg:<type>:<name>:<description>\n
Types are defined in commands.arg_types.
Note that this commit removes support for single letter
shortcuts in command options.
If a command is not properly documented, a warning is issued
with print(), because no logger is available at this point.
This removes support for Ledger HW.1 and "Nano" (non-S) devices.
These were manufactured/sold around 2015-2016, and are long unsupported by the upstream vendor.
We previously added a deprecation warning to the GUI [0] released in 4.3.3 (2023-01-02), to warn owners of these devices.
This PR now fully removes support.
As a consequence, the unmaintained btchip-python dependency can now be removed, which solves [1].
[0]: 9b82eb6d06
[1]: https://github.com/spesmilo/electrum/issues/9370#issuecomment-2593675364
if they use a software keystore.
This excludes hardware wallets and watching-only wallet.
Also, this forbids creation of new channels in those wallets,
in case lightning was previously enabled.
Fixes#9440
- make plugin commands start with plugin name + underscore
- plugin_name must be passed to the plugin_command decorator
- fixes:
- remove plugin_commands (unneeded)
- func_wrapper must await func()
- setattr(Commands, name, func_wrapper)
- add push/pull commands to labels plugin
