安装 webpack_loader (webpack-template-loader) 在 assignment_tag 上出现属性错误答案

【问题标题】：Installing webpack_loader (webpack-template-loader) gives attribute error on assignment_tag安装 webpack_loader (webpack-template-loader) 在 assignment_tag 上出现属性错误
【发布时间】：2019-10-18 10:19:42
【问题描述】：

我正在尝试将 webpack-template-loader 添加到我的项目中 (djang=2.2.1, django-webpack-loader===0.2.4, webpack-bundle-tracker=^0.4.3,webpack=^ 4.41.2)。我已尽我所能按照here 的指示进行操作。

我的 settings.py 如下所示：

INSTALLED_APPS = [
    ...
    'webpack_loader',
]


# webpack loader
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'assets'),
)

WEBPACK_LOADER = {
    'DEFAULT': {
        'CACHE': False,
        'BUNDLE_DIR_NAME': 'assets/',
        'POLL_INTERVAL': 0.1,
        'TIMEOUT': None,
        'IGNORE': [r'.+\.hot-update.js', r'.+\.map']
    }
}

在我的 package.json 中，我有以下内容：

{
    ...
    "scripts": {
        "build": "webpack --config ./webpack/prod.config.js",
        "build-dev": "webpack --config ./webpack/dev.config.js --display-error-details"
    },
    "dependencies": {
        "webpack": "^4.41.2",
        "webpack-bundle-tracker": "^0.4.3",
        "webpack-cli": "^3.3.9"
    }
}

并运行 npm run build-dev 正确构建我的包而不会出错。在将'webpack_loader' 添加到INSTALLED_APPS 时，我的服务器停止转动，并且出现错误：

Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/django/template/utils.py", line 66, in __getitem__
    return self._engines[alias]
KeyError: 'django'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/lib/python3.6/threading.py", line 916, in _bootstrap_inner
    self.run()
  File "/usr/local/lib/python3.6/threading.py", line 864, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/utils/autoreload.py", line 54, in wrapper
    fn(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/runserver.py", line 117, in inner_run
    self.check(display_num_errors=True)
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 390, in check
    include_deployment_checks=include_deployment_checks,
  File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 377, in _run_checks
    return checks.run_checks(**kwargs)
  File "/usr/local/lib/python3.6/site-packages/django/core/checks/registry.py", line 72, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/usr/local/lib/python3.6/site-packages/django/contrib/admin/checks.py", line 79, in check_dependencies
    for engine in engines.all():
  File "/usr/local/lib/python3.6/site-packages/django/template/utils.py", line 90, in all
    return [self[alias] for alias in self]
  File "/usr/local/lib/python3.6/site-packages/django/template/utils.py", line 90, in <listcomp>
    return [self[alias] for alias in self]
  File "/usr/local/lib/python3.6/site-packages/django/template/utils.py", line 81, in __getitem__
    engine = engine_cls(params)
  File "/usr/local/lib/python3.6/site-packages/django/template/backends/django.py", line 25, in __init__
    options['libraries'] = self.get_templatetag_libraries(libraries)
  File "/usr/local/lib/python3.6/site-packages/django/template/backends/django.py", line 43, in get_templatetag_libraries
    libraries = get_installed_libraries()
  File "/usr/local/lib/python3.6/site-packages/django/template/backends/django.py", line 108, in get_installed_libraries
    for name in get_package_libraries(pkg):
  File "/usr/local/lib/python3.6/site-packages/django/template/backends/django.py", line 121, in get_package_libraries
    module = import_module(entry[1])
  File "/usr/local/lib/python3.6/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 994, in _gcd_import
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 678, in exec_module
  File "<frozen importlib._bootstrap>", line 219, in _call_with_frames_removed
  File "/usr/local/lib/python3.6/site-packages/webpack_loader/templatetags/webpack_loader.py", line 50, in <module>
    @register.assignment_tag
AttributeError: 'Library' object has no attribute 'assignment_tag'

我正在努力解决这个问题，我在 deprecated assignment 标签上看到了this 问题，但我不确定如何或在哪里覆盖它，从错误消息来看，它似乎是引导问题的副产品，而不是根本原因。

谁能解释一下为什么我会看到这个错误？

【问题讨论】：

标签： django webpack

【解决方案1】：

我将其添加为结束问题的答案，但这并不是特别令人满意，所以如果有人想在这背后添加逻辑，我肯定会更改已接受的答案以获得更好的答案。

问题与导入有关，特别是在 webpack_loader 处理 assignment_tag，因为它应该已导入：

assignment_tag = register.simple_tag if VERSION >= (1, 9) else register.assignment_tag
@assignment_tag
def get_files(bundle_name, extension=None, config='DEFAULT'):
    ...

无论出于何种原因，三元运算符也没有将版本重新设置为 > 1.9。

当我们像应用程序一样添加 repo（而不是使用 pipenv）时，问题就消失了。

不是一个很好的解决方案，但仍然是一个解决方案

【讨论】：