traefik/docs/content/routing/overview.md
2019-04-15 11:14:05 +02:00

4.7 KiB

Overview

What's Happening to the Requests? {: .subtitle }

Let's zoom on Traefik's architecture and talk about the components that enable the routes to be created.

First, when you start Traefik, you define entrypoints (in their most basic forms, they are port numbers). Then, connected to these entrypoints, routers analyze the incoming requests to see if they match a set of rules. If they do, the router might transform the request using pieces of middleware before forwarding them to your services.

Architecture

Clear Responsibilities

  • Providers discover the services that live on your infrastructure (their IP, health, ...)
  • Entrypoints listen for incomming traffic (ports, ...)
  • Routers analyse the requests (host, path, headers, SSL, ...)
  • Services forward the request to your services (load balancing, ...)
  • Middlewares may update the request or make decisions based on the request (authentication, rate limiting, headers, ...)

Example with a File Provider

Below is an example of a full configuration file for the file provider that forwards http://domain/whoami/ requests to a service reachable on http://private/whoami-service/. In the process, Traefik will make sure that the user is authenticated (using the BasicAuth middleware).

[entryPoints]
   [entryPoints.web]
      address = ":8081" # Listen on port 8081 for incoming requests

[providers]
   [providers.file] # Enable the file provider to define routers / middlewares / services in a file

[http] # http routing section
    [http.routers]
       [http.routers.to-whoami] # Define a connection between requests and services
          rule = "Host(domain) && PathPrefix(/whoami/)"
          middlewares = ["test-user"] # If the rule matches, applies the middleware
          service = "whoami" # If the rule matches, forward to the whoami service (declared below)

    [http.middlewares]
       [http.middlewares.test-user.basicauth] # Define an authentication mechanism
          users = ["test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"]

    [http.services]
       [http.services.whoami.loadbalancer] # Define how to reach an existing service on our infrastructure
          [[http.services.whoami.loadbalancer.servers]]
             url = "http://private/whoami-service"

!!! note "The File Provider"

In this example, we use the [file provider](../providers/file.md).
Even if it is one of the least magical way of configuring Traefik, it explicitly describes every available notion.

!!! note "HTTP / TCP"

In this example, we've defined routing rules for http requests only.
Traefik also supports TCP requests. To add [TCP routers](./routers/index.md) and [TCP services](./services/index.md), declare them in a TCP section like in the following.

??? example "Adding a TCP route for TLS requests on whoami.traefik.io"

    ```toml
    [entryPoints]
       [entryPoints.web]
          address = ":8081" # Listen on port 8081 for incoming requests

    [providers]
       [providers.file] # Enable the file provider to define routers / middlewares / services in a file

    [http] # http routing section
        [http.routers]
           [http.routers.to-whoami] # Define a connection between requests and services
              rule = "Host(`domain`) && PathPrefix(/whoami/)"
              middlewares = ["test-user"] # If the rule matches, applies the middleware
              service = "whoami" # If the rule matches, forward to the whoami service (declared below)

        [http.middlewares]
           [http.middlewares.test-user.basicauth] # Define an authentication mechanism
              users = ["test:$apr1$H6uskkkW$IgXLP6ewTrSuBkTrqE8wj/"]

        [http.services]
           [http.services.whoami.loadbalancer] # Define how to reach an existing service on our infrastructure
              [[http.services.whoami.loadbalancer.servers]]
                 url = "http://private/whoami-service"

       [tcp]
          [tcp.routers]
             [tcp.routers.to-whoami-tcp]
                 rule = "HostSNI(`whoami-tcp.traefik.io`)"
                 service = "whoami-tcp"
                 [tcp.routers.to-whoami-tcp.tls]

          [tcp.services]
             [tcp.services.whoami-tcp.loadbalancer]
                [[tcp.services.whoami-tcp.loadbalancer.servers]]
                   address = "xx.xx.xx.xx:xx"
    ```