首页 > 解决方案 > 用 Django 和 Kubernetes 部署 prometheus,如何让它爬取 Django 应用程序?

问题描述

我在 Kubernetes 中部署了一个 Django 项目,我正在尝试将 Prometheus 部署为监控工具。我已经成功地完成了项目中需要包含django_prometheus的所有步骤,并且在本地我可以去尝试localhost:9090查询指标。

我还将 Prometheus 部署到我的 Kubernetes 集群中,在kubectl port-forward ...Prometheus pod 上运行后,我可以看到我的 Kubernetes 资源的一些指标。

我有点困惑的是如何使部署的 Django 应用程序指标像其他人一样在 Prometheus 仪表板上可用。我将我的应用程序部署在default命名空间中,并将普罗米修斯部署在monitoring专用命名空间中。我想知道我在这里错过了什么。我是否需要根据工作人员的数量或类似的东西将服务和部署上的端口从 8000 公开到 8005?

我的 Django 应用程序使用 gunicorn 运行,如下supervisord所示:

[program:gunicorn]
command=gunicorn --reload --timeout 200000 --workers=5 --limit-request-line 0 --limit-request-fields 32768 --limit-request-field_size 0 --chdir /code/ my_app.wsgi
apiVersion: v1
kind: Service
metadata:
  name: my_app
  namespace: default
spec:
  ports:
  - name: http
    port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: my-app
  sessionAffinity: None
  type: ClusterIP

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app: my-app
  name: my-app-deployment
  namespace: default
spec:
  progressDeadlineSeconds: 600
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: my-app
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      labels:
        app: my-app
    spec:
      containers:
      - image: ...
        imagePullPolicy: IfNotPresent
        name: my-app
        ports:
        - containerPort: 80
          name: http
          protocol: TCP
      dnsPolicy: ClusterFirst
      imagePullSecrets:
      - name: regcred
      restartPolicy: Always
      schedulerName: default-scheduler
      terminationGracePeriodSeconds: 30

apiVersion: v1
data:
  prometheus.rules: |-
    ... some rules
  prometheus.yml: |-
    global:
      scrape_interval: 5s
      evaluation_interval: 5s
    rule_files:
      - /etc/prometheus/prometheus.rules
    scrape_configs:
      - job_name: prometheus
        static_configs:
        - targets:
          - localhost:9090

      - job_name: my-app
        metrics_path: /metrics
        static_configs:
          - targets:
            - localhost:8000

      - job_name: 'node-exporter'
        kubernetes_sd_configs:
          - role: endpoints
        relabel_configs:
        - source_labels: [__meta_kubernetes_endpoints_name]
          regex: 'node-exporter'
          action: keep

kind: ConfigMap
metadata:
  labels:
    name: prometheus-config
  name: prometheus-config
  namespace: monitoring

标签: djangokubernetesprometheus

解决方案


无需将应用程序暴露在集群之外。

利用 Kubernetes 服务发现,将作业添加到抓取服务、Pod 或两者:

- job_name: 'kubernetes-service-endpoints'
  kubernetes_sd_configs:
  - role: endpoints
  relabel_configs:
  - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_scrape]
    action: keep
    regex: true
  - source_labels: [__address__, __meta_kubernetes_service_annotation_prometheus_io_port]
    action: replace
    regex: ([^:]+)(?::\d+)?;(\d+)
    replacement: $1:$2
    target_label: __address__
  - source_labels: [__meta_kubernetes_service_annotation_prometheus_io_path]
    action: replace
    target_label: __metrics_path__
    regex: (.+)
  - source_labels: [__meta_kubernetes_namespace]
    action: replace
    target_label: namespace
    regex: (.+)
  - regex: __meta_kubernetes_service_label_(.+)
    action: labelmap
  - regex: 'app_kubernetes_io_(.+)'
    action: labeldrop
  - regex: 'helm_sh_(.+)'
    action: labeldrop
- job_name: 'kubernetes-pods'
  kubernetes_sd_configs:
  - role: pod
  relabel_configs:
  - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_scrape]
    action: keep
    regex: true
  - source_labels: [__address__, __meta_kubernetes_pod_annotation_prometheus_io_port]
    action: replace
    regex: ([^:]+)(?::\d+)?;(\d+)
    replacement: $1:$2
    target_label: __address__
  - source_labels: [__meta_kubernetes_pod_annotation_prometheus_io_path]
    action: replace
    target_label: __metrics_path__
    regex: (.+)
  - source_labels: [__meta_kubernetes_namespace]
    action: replace
    target_label: namespace
    regex: (.+)
  - source_labels: [__meta_kubernetes_pod_node_name]
    action: replace
    target_label: host
    regex: (.+)
  - source_labels: [__meta_kubernetes_pod_name]
    action: replace
    target_label: pod
    regex: (.+)
  - regex: __meta_kubernetes_pod_label_(.+)
    action: labelmap
  - regex: 'app_kubernetes_io_(.+)'
    action: labeldrop
  - regex: 'helm_sh_(.+)'
    action: labeldrop

然后,使用以下命令注释服务:

metadata:
  annotations:
    prometheus.io/scrape: "true"
    prometheus.io/port: "80"
    prometheus.io/path: "/metrics"

和部署:

spec:
  template:
    metadata:
     annotations:
      prometheus.io/scrape: "true"
      prometheus.io/port: "80"
      prometheus.io/path: "/metrics"

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