用python继承SinkFunction类将kafaka数据流传入http中的写法
时间: 2024-03-12 10:49:28 浏览: 193
python中,类的继承,实例及结果(必须知道的五点)
在Python中使用Flink,继承`SinkFunction`类将Kafka数据流传入HTTP的写法如下:
```python
import requests
from pyflink.common.serialization import SimpleStringSchema
from pyflink.datastream import StreamExecutionEnvironment
from pyflink.datastream.connectors import FlinkKafkaConsumer, StreamingFileSink
from pyflink.datastream.functions import SinkFunction
class HttpSink(SinkFunction):
def __init__(self, url):
self.url = url
def invoke(self, value):
headers = {'Content-type': 'application/json', 'Accept': 'text/plain'}
response = requests.post(self.url, data=value, headers=headers)
print(response.text)
env = StreamExecutionEnvironment.get_execution_environment()
# Kafka consumer configuration
kafka_props = {
'bootstrap.servers': 'localhost:9092',
'group.id': 'test-group'
}
# Create a FlinkKafkaConsumer instance
kafka_consumer = FlinkKafkaConsumer(
'test-topic',
SimpleStringSchema(),
properties=kafka_props
)
# Add the Kafka source to the execution environment
kafka_stream = env.add_source(kafka_consumer)
# Add the HTTP sink to the execution environment
http_sink = kafka_stream.add_sink(HttpSink('http://localhost:8080'))
http_sink.set_parallelism(1)
env.execute('Kafka to HTTP')
```
在上述代码中,我们定义了一个`HttpSink`类,继承了`SinkFunction`类,并实现了其中的`invoke`方法,该方法将Kafka数据流传入HTTP中。在`invoke`方法中,我们使用`requests`库发送HTTP请求,并将Kafka数据作为请求体传入。然后,我们将该类的实例`http_sink`添加到数据流中,并指定并行度为1。最后,我们通过`env.execute()`方法启动Flink程序。
需要注意的是,上述代码仅为示例代码,实际上需要根据实际需求进行修改。
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