更简单的 Traefik 2 使用方式
经过一年多的实践，对于使用 Traefik 有了一些更深入的体会，本篇先来介绍如何简化使用，后续会逐步展开聊聊如何在云上使用这款“云原生”工具，以及结合它做一些提升业务效率和开发效率的实践。

在 Traefik 2 使用指南，愉悦的开发体验、配置基于Traefik v2的 Web 服务器 文章中，使用 Traefik 的方案引入了比较多的配置，如果你并不是在一个复杂场景使用，这样的配置是可以简化的。

简化程序配置文件
一般情况下将参数变为配置，更利于在版本控制软件中进行版本管理。在 v2 版本中，因为有了动态配置的概念，传统的固定配置，使用简写的参数来替换，并记录在容器启动配置中，可以在减少分发文件数量的情况下，达到相同的效果。

使用参数取代 traefik.toml
在之前的文章中，我提供了一般情况下，使用的默认配置内容：

[global]
  checkNewVersion = false
  sendAnonymousUsage = false

[log]
  level = "WARN"
  format = "common"

[api]
  dashboard = true
  insecure = true

[ping]

[accessLog]

[providers]
  [providers.docker]
    watch = true
    exposedByDefault = false
    endpoint = "unix:///var/run/docker.sock"
    swarmMode = false
    useBindPortIP = false
    network = "traefik"
  [providers.file]
    watch = true
    directory = "/etc/traefik/config"
    debugLogGeneratedTemplate = true

[entryPoints]
  [entryPoints.http]
    address = ":80"
  [entryPoints.https]
    address = ":443"

想要达到相同的效果，只需要在 command 字段内添加下面的内容即可：

version: '3'

services:

  traefik:
...
    command:
      - "--global.sendanonymoususage=false"
      - "--global.checknewversion=false"
      - "--entrypoints.http.address=:80"
      - "--entrypoints.https.address=:443"
      - "--api=true"
      - "--api.insecure=true"
      - "--api.dashboard=true"
      - "--api.debug=false"
      - "--ping=true"
      - "--log.level=warn"
      - "--log.format=common"
      - "--accesslog=false"
      - "--providers.docker=true"
      - "--providers.docker.watch=true"
      - "--providers.docker.exposedbydefault=false"
      - "--providers.docker.endpoint=unix:///var/run/docker.sock"
      - "--providers.docker.swarmMode=false"
      - "--providers.docker.useBindPortIP=false"
      - "--providers.docker.network=traefik"
      - "--providers.file=true"
      - "--providers.file.watch=true"
      - "--providers.file.directory=/etc/traefik/config"
      - "--providers.file.debugloggeneratedtemplate=true"
...

现在，你就可以将 traefik.toml 配置文件删除掉了。

简化 dashboard.toml
前文中，我们将 Traefik 的内置 dashboard 等路由通过配置文件来定义，像下面这样。

[http.middlewares.dash-compress.compress]
[http.middlewares.dash-auth.basicAuth]
  users = [
    "test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/",
  ]

[http.routers.dashboard-redirect-https]
  rule = "Host(`dashboard.lab.io`, `dashboard.lab.com`)"
  entryPoints = ["http"]
  service = "noop"
  middlewares = ["https-redirect"]
  priority = 100

[http.routers.dashboard]
  rule = "Host(`dashboard.lab.io`, `dashboard.lab.com`)"
  entrypoints = ["https"]
  service = "dashboard@internal"
  middlewares = ["dash-compress"]
  [http.routers.dashboard.tls]

[http.routers.api]
  rule = "Host(`dashboard.lab.io`, `dashboard.lab.com`) && PathPrefix(`/api`)"
  entrypoints = ["https"]
  service = "api@internal"
  middlewares = ["dash-compress"]
  [http.routers.api.tls]

[http.routers.ping]
  rule = "Host(`dashboard.lab.io`, `dashboard.lab.com`) && PathPrefix(`/ping`)"
  entrypoints = ["https"]
  service = "ping@internal"
  middlewares = ["dash-compress"]
  [http.routers.ping.tls]

其实，只需要将配置保留剩下这两条需要被预先定义的“中间件”即可，如果你不需要页面压缩，或者不需要访问密码，那么也可以不对下面的内容进行保存：

[http.middlewares.dash-compress.compress]
[http.middlewares.dash-auth.basicAuth]
  users = [
    "test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/",
  ]

接着在容器配置中添加一些 traefik 能够解析处理的规则在 labels 字段中即可：

version: '3'

services:

  traefik:
...    
    labels:
      - "traefik.enable=true"
      - "traefik.docker.network=traefik"
      # 默认请求转发 https 端口
      - "traefik.http.routers.traefik-dash-default.middlewares=https-redirect@file"
      - "traefik.http.routers.traefik-dash-default.entrypoints=http"
      - "traefik.http.routers.traefik-dash-default.rule=Host(`dashboard.guava.lab.com`)"
      - "traefik.http.routers.traefik-dash-default.service=dashboard@internal"
      # 处理网页
      - "traefik.http.routers.traefik-dash-web.entrypoints=https"
      - "traefik.http.routers.traefik-dash-web.rule=Host(`dashboard.guava.lab.com`) && PathPrefix(`/`)"
      - "traefik.http.routers.traefik-dash-web.tls=true"
      - "traefik.http.routers.traefik-dash-web.service=dashboard@internal"
      # 处理接口
      - "traefik.http.routers.traefik-dash-api.entrypoints=https"
      - "traefik.http.routers.traefik-dash-api.rule=Host(`dashboard.guava.lab.com`) && (PathPrefix(`/api`) || PathPrefix(`/dashboard`))"
      - "traefik.http.routers.traefik-dash-api.tls=true"
      - "traefik.http.routers.traefik-dash-api.service=api@internal"
...

单独抽象保存的 default.toml 配置
虽然我们将 90% 的内容都迁移到了 compose 配置文件中，但是还是有一些内容暂时是不好进行重写的，比如下面提到的“内容Gzip压缩”和“HTTP转发HTTPS”：

# 提供 Gzip 压缩
[http.middlewares.gzip.compress]

# tricks 实现，提供 HTTP 默认转发 HTTPS
# https://github.com/containous/traefik/issues/4863#issuecomment-491093096
[http.services]
  [http.services.noop.LoadBalancer]
     [[http.services.noop.LoadBalancer.servers]]
        url = "" # or url = "localhost"

[http.routers]
  [http.routers.https-redirect]
    entryPoints = ["http"]
    rule = "HostRegexp(`{any:.*}`)"
    middlewares = ["https-redirect"]
    service = "noop"

[http.middlewares.https-redirect.redirectScheme]
  scheme = "https"

这里倒不是说不能够在应用内配置，而是如果这两个中间件在应用内配置，会出现每个应用都需要配置重复配置的问题。尽管独立的配置会让应用的可迁移性更好，然而这份配置可以提供不论是在本地、私有云，还是公有云 SLB 环境下的一致行为，维护一份配置，总比维护几份要来的方便，不是吗？

完整的容器配置
一如既往，这里给出完整的 compose 配置：

version: '3'

services:

  traefik:
    container_name: traefik
    image: traefik:v2.3.4
    restart: always
    ports:
      - 80:80
      - 443:443
    networks:
      - traefik
    command:
      - "--global.sendanonymoususage=false"
      - "--global.checknewversion=false"
      - "--entrypoints.http.address=:80"
      - "--entrypoints.https.address=:443"
      - "--api=true"
      - "--api.insecure=true"
      - "--api.dashboard=true"
      - "--api.debug=false"
      - "--ping=true"
      - "--log.level=warn"
      - "--log.format=common"
      - "--accesslog=false"
      - "--providers.docker=true"
      - "--providers.docker.watch=true"
      - "--providers.docker.exposedbydefault=false"
      - "--providers.docker.endpoint=unix:///var/run/docker.sock"
      - "--providers.docker.swarmMode=false"
      - "--providers.docker.useBindPortIP=false"
      - "--providers.docker.network=traefik"
      - "--providers.file=true"
      - "--providers.file.watch=true"
      - "--providers.file.directory=/etc/traefik/config"
      - "--providers.file.debugloggeneratedtemplate=true"
    volumes:
      # 仅限标准的 Linux 环境
      - /etc/localtime:/etc/localtime:ro
      - /etc/timezone:/etc/timezone:ro
      - /var/run/docker.sock:/var/run/docker.sock:ro
      - ./config/:/etc/traefik/config/:ro
      - ./ssl/:/data/ssl/:ro
    labels:
      - "traefik.enable=true"
      - "traefik.docker.network=traefik"
      # 默认请求转发 https 端口
      - "traefik.http.routers.traefik-dash-default.middlewares=https-redirect@file"
      - "traefik.http.routers.traefik-dash-default.entrypoints=http"
      - "traefik.http.routers.traefik-dash-default.rule=Host(`dashboard.guava.lab.com`)"
      - "traefik.http.routers.traefik-dash-default.service=dashboard@internal"
      # 处理网页
      - "traefik.http.routers.traefik-dash-web.entrypoints=https"
      - "traefik.http.routers.traefik-dash-web.rule=Host(`dashboard.guava.lab.com`) && PathPrefix(`/`)"
      - "traefik.http.routers.traefik-dash-web.tls=true"
      - "traefik.http.routers.traefik-dash-web.service=dashboard@internal"
      # 处理接口
      - "traefik.http.routers.traefik-dash-api.entrypoints=https"
      - "traefik.http.routers.traefik-dash-api.rule=Host(`dashboard.guava.lab.com`) && (PathPrefix(`/api`) || PathPrefix(`/dashboard`))"
      - "traefik.http.routers.traefik-dash-api.tls=true"
      - "traefik.http.routers.traefik-dash-api.service=api@internal"
    healthcheck:
      test: ["CMD-SHELL", "wget -q --spider --proxy off localhost:8080/ping || exit 1"]
      interval: 3s
      retries: 12
    logging:
      driver: "json-file"
      options:
        max-size: "1m"

networks:
  traefik:
    external: true

最后
官方在前一阵推出了 https://traefik.io/traefik-pilot/，除了作为统一的管理中心之外，还提供了许多有用的中间件，比如请求/响应头改写、IP 禁止名单、IP地址转换、fail2ban 等等。

因为暂时官方无意将 pilot 开源（可能也会是长期状况），如果你不介意“联公网”使用，可以试试注册 pilot 使用。

--EOF