使用Prometheus监控Flask微服务

几行代码，您的应用程序就会生成指标，哇！

为了了解prometheus_ flask_exporter的工作方式，一个简单的示例就足够了：

from flask import Flask
from prometheus_flask_exporter import PrometheusMetrics

app = Flask(__name__)
metrics = PrometheusMetrics(app)

@app.route('/')
def main():
    return 'OK'

这就是您入门所需的一切！通过添加导入和一行以初始化PrometheusMetrics，您可以获取在其注册的Flask应用程序的/ metrics端点上显示的请求持续时间指标和请求计数器，以及从基础Prometheus客户端库获得的任何默认指标。

您可以在GitHub存储库中找到一个易于使用的示例，该示例启动Prometheus和Grafana的实例以及一个演示应用程序以生成如下所示的指标：

README , , Prometheus, .

, README .

. PrometheusMetrics, metrics, , , :

• @metrics.counter(..)

• @metrics.gauge(..)

• @metrics.summary(..)

• @metrics.histogram(..)

, . , . :

from flask import Flask, request
from prometheus_flask_exporter import PrometheusMetrics

app = Flask(__name__)

# group by endpoint rather than path
metrics = PrometheusMetrics(app, group_by='endpoint')

@app.route('/collection/:collection_id/item/:item_id')
@metrics.counter(
    'cnt_collection', 'Number of invocations per collection', labels={
        'collection': lambda: request.view_args['collection_id'],
        'status': lambda resp: resp.status_code
    })
def get_item_from_collection(collection_id, item_id):
    pass

/collection/10002/item/76 , cnt_collection{collection = "10002", status = "200"}, ( ) :

• flask_http_request_duration_seconds - HTTP- Flask ,

• flask_http_request_total - HTTP-

, , , . README , , .

app = Flask(__name__)
metrics = PrometheusMetrics(app)

@app.route('/')
def main():
    pass  # requests tracked by default

@app.route('/skip')
@metrics.do_not_track()
def skip():
    pass  # default metrics are not collected

# custom metric to be applied to multiple endpoints
common_counter = metrics.counter(
    'by_endpoint_counter', 'Request count by endpoints',
    labels={'endpoint': lambda: request.endpoint}
)

@app.route('/common/one')
@common_counter
def endpoint_one():
    pass  # tracked by the custom and the default metrics

@app.route('/common/two')
@common_counter
def endpoint_two():
    pass  # also tracked by the custom and the default metrics

# register additional default metrics
metrics.register_default(
    metrics.counter(
        'by_path_counter', 'Request count by request paths',
        labels={'path': lambda: request.path}
    )
)

, uWSGI Gunicorn. , .

, /metrics Flask, Prometheus.

Prometheus Flask :

scrape_configs:
  - job_name: 'example'

    dns_sd_configs:
      - names: ['app']
        port: 5000
        type: A
        refresh_interval: 5s

GitHub. , Prometheus Flask http://app:5000/metrics, IP-, , Kubernetes Docker Swarm.

, , , , path=None PrometheusMetrics.

from flask import Flask, request
from prometheus_flask_exporter import PrometheusMetrics

app = Flask(__name__)
metrics = PrometheusMetrics(app, path=None)

...

metrics.start_http_server(5099)

start_http_server(port), HTTP-, 5099 . , , Flask, /metrics, URI , register_endpoint(..), .

• rycus86/prometheus_flask_exporter - Prometheus

• prometheus-flask-exporter README - ,

• prometheus-flask-exporter examples - Flask

• PyPI上的prometheus-flask-exporter- 该项目在PyPI上

• prometheus / client_python  -Python的官方Prometheus客户端库

如果您决定尝试一下，请随时在GitHub上发布问题，或留下您的评论，反馈和建议！

谢谢！