32 lines
1.1 KiB
Markdown
32 lines
1.1 KiB
Markdown
# Streaming
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Sanic allows you to stream content to the client with the `stream` method. This method accepts a coroutine callback which is passed a `StreamingHTTPResponse` object that is written to. A simple example is like follows:
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```python
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from sanic import Sanic
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from sanic.response import stream
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app = Sanic(__name__)
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@app.route("/")
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async def test(request):
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async def sample_streaming_fn(response):
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response.write('foo,')
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response.write('bar')
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return stream(sample_streaming_fn, content_type='text/csv')
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```
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This is useful in situations where you want to stream content to the client that originates in an external service, like a database. For example, you can stream database records to the client with the asynchronous cursor that `asyncpg` provides:
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```python
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@app.route("/")
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async def index(request):
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async def stream_from_db(response):
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conn = await asyncpg.connect(database='test')
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async with conn.transaction():
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async for record in conn.cursor('SELECT generate_series(0, 10)'):
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response.write(record[0])
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return stream(stream_from_db)
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``` |