28 lines
736 B
Markdown
28 lines
736 B
Markdown
# Signals
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Signals allow you to send notifications to multiple subscribers when the specific event occured.
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Signaling is provided by [Blinker](http://pythonhosted.org/blinker/) library and
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Sanic has few built-in signals:
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* `request_started`: Sent when the request processing has started.
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* `request_finished`: Sent when the request processing has finished.
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## Examples
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```python
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from sanic.signals import request_started
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import my_realtime_stat
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app = Sanic(__name__)
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@request_started.connect
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def collect_stats(request):
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my_realtime_stat.incoming_requests.incr(request.url)
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@request_finished.connect
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def count_errors(response):
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if response.status != 200:
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my_realtime_stat.error_responses.incr(response.status)
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```
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