spesmilo / electrum / 4917020841476096

61%

master: 63%

Build Type

Pull #9655

CirrusCI

Committed by SomberNight

Commit Message

plugins: better handle exceptions in __init__

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/plu... (continued)

Pull Request Pull Request #9655: plugins: better handle exceptions in `__init__`

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