Sanic-Plugins-Framework 0.9.5

增强的中间件系统

Sanic插件框架中的中间件系统既基于又扩展了原生Sanic中间件系统。而不是简单地有两个中间件队列（“请求”和“响应”），SPF中的中间件系统使用五个额外的队列。

• 请求-预：这些中间件在应用程序自己的请求中间件之前运行。

• 请求-后置：这些中间件在应用自身的请求中间件之后运行。

• 响应-前置：这些中间件在应用自身的响应中间件之前运行。

• 响应-后置：这些中间件在应用自身的响应中间件之后运行。

• 清理：这些中间件在所有上述中间件之后运行，在响应发送后运行，即使响应为空也会运行。

因此，作为插件开发者，您可以选择您的中间件是在应用自身的中间件之前还是之后执行。

您还可以为您的插件中的每个中间件分配优先级，以便更精确地控制中间件的执行顺序，尤其是在应用使用多个插件时。

上下文对象管理器

许多人都发现Sanic缺少一个上下文对象。SPF提供了多个上下文对象，可用于不同的目的。

• 共享上下文：所有注册在SPF中的插件都可以访问一个共享的、持久的上下文对象，任何人都可以读取和写入。

• 请求上下文：所有插件都可以访问一个共享的临时上下文对象，任何人都可以读取和写入，该对象在请求开始时创建，在请求完成后删除。

• 插件上下文：所有插件都拥有自己的私有持久上下文对象，只有该插件可以读取和写入。

• 插件请求上下文：所有插件都拥有一个临时私有上下文对象，该对象在请求开始时创建，在请求完成后删除。

安装

使用pip或easy_install安装此扩展。

$ pip install -U sanic-plugins-framework

使用

使用Sanic插件框架编写的简单插件将类似于以下示例

# Source: my_plugin.py
from spf import SanicPlugin
from sanic.response import text

class MyPlugin(SanicPlugin):
    def __init__(self, *args, **kwargs):
        super(MyPlugin, self).__init__(*args, **kwargs)
        # do pre-registration plugin init here.
        # Note, context objects are not accessible here.

    def on_registered(self, context, reg, *args, **kwargs):
        # do post-registration plugin init here
        # We have access to our context and the shared context now.
        context.my_private_var = "Private variable"
        shared = context.shared
        shared.my_shared_var = "Shared variable"

my_plugin = MyPlugin()

# You don't need to add any parameters to @middleware, for default behaviour
# This is completely compatible with native Sanic middleware behaviour
@my_plugin.middleware
def my_middleware(request)
    h = request.headers
    #Do request middleware things here

#You can tune the middleware priority, and add a context param like this
#Priority must be between 0 and 9 (inclusive). 0 is highest priority, 9 the lowest.
#If you don't specify an 'attach_to' parameter, it is a 'request' middleware
@my_plugin.middleware(priority=6, with_context=True)
def my_middleware2(request, context):
    context['test1'] = "test"
    print("Hello world")

#Add attach_to='response' to make this a response middleware
@my_plugin.middleware(attach_to='response', with_context=True)
def my_middleware3(request, response, context):
    # Do response middleware here
    return response

#Add relative='pre' to make this a response middleware run _before_ the
#application's own response middleware
@my_plugin.middleware(attach_to='response', relative='pre', with_context=True)
def my_middleware4(request, response, context):
    # Do response middleware here
    return response

#Add attach_to='cleanup' to make this run even when the Response is None.
#This queue is fired _after_ response is already sent to the client.
@my_plugin.middleware(attach_to='cleanup', with_context=True)
def my_middleware5(request, context):
    # Do per-request cleanup here.
    return None

#Add your plugin routes here. You can even choose to have your context passed in to the route.
@my_plugin.route('/test_plugin', with_context=True)
def t1(request, context):
    words = context['test1']
    return text('from plugin! {}'.format(words))

应用开发者可以在其代码中使用您的插件，如下所示

# Source: app.py
from sanic import Sanic
from spf import SanicPluginsFramework
from sanic.response import text
import my_plugin

app = Sanic(__name__)
spf = SanicPluginsFramework(app)
assoc = spf.register_plugin(my_plugin)

# ... rest of user app here

支持使用配置文件定义在SPF添加到应用时加载的插件列表。

# Source: spf.ini
[plugins]
MyPlugin
AnotherPlugin=ExampleArg,False,KWArg1=True,KWArg2=33.3

# Source: app.py
app = Sanic(__name__)
app.config['SPF_LOAD_INI'] = True
app.config['SPF_INI_FILE'] = 'spf.ini'
spf = SanicPluginsFramework(app)

# We can get the assoc object from SPF, it is already registered
assoc = spf.get_plugin_assoc('MyPlugin')

或者，如果开发者更喜欢使用旧方法（如Flask方式），他们仍然可以这样操作

# Source: app.py
from sanic import Sanic
from sanic.response import text
from my_plugin import MyPlugin

app = Sanic(__name__)
# this magically returns your previously initialized instance
# from your plugin module, if it is named `my_plugin` or `instance`.
assoc = MyPlugin(app)

# ... rest of user app here

贡献

有问题、评论或改进建议？请在Github上创建问题

致谢

Ashley Sommer ashleysommer@gmail.com