Better debugging experience with HMR
Automatic reload your project when files are modified.
No need to modify your source code. Works in any environment.
Supported Syntax:
- ✅
import X - ✅
from X import Y
Supported Types:
- ✅
Module - ✅
Function - ✅
Class
pip install python-hmrCaution
From v0.3.0, there is only one API, hmr.reload.
Import your dev packages as usual. And add 2 lines for automatically reloading.
importdevimporthmrdev=hmr.reload(dev)If you have multiple modules to reload, you can do it like this.
fromdevimportrun1, run2importhmrrun1, run2=hmr.reload(run1, run2)Now you are ready to go! Try to modify the run1 or run2
and see the magic happen.
When you try to add HMR for a function or class, remember to pass the name of the function or class instance without parenthesis.
fromdevimportRunnerimporthmrRunner=hmr.reload(Runner)
a=Runner()
b=Runner()Important
Here, when both a and b will be updated after reloading. This may be helpful
if you have an expansive state store within the class instance.
However, it's suggested to reinitialize the class instance after reloading.
Use functools.wraps to preserve signature of your function, or the function information will be replaced by the decorator itself.
importfunctoolsdefwork(f):
@functools.wraps(f)defargs(*arg, **kwargs):
returnf(*arg, **kwargs)
returnargsIf your application is stateful, you can exclude the state from being reloaded.
For simplicity, you can group all your state variable into the same .py file like state.py
and exclude that from being reloaded.
Make sure you know what you are doing. This could lead to unexpected behavior and unreproducible bugs.
importdevimporthmrdev=hmr.reload(dev, exclude=["dev.state"])In this way dev/state.py will not be reloaded, the state will persist.
This also apply when reloading a function or class.
fromdevimportrunimporthmrrun=hmr.reload(run, exclude=["dev.state"])Inspired from the following package.