Consul Integration

Running Aralez as service mesh for Nomad services with Consul

Make sure you have access to Consul API. Add Consul servers in upstreams file. If consul authentication is enabled , get API token and add to config file. All configs except authentication at virtual host / path level are working as with configuration via plain config file .

Aralez can be deployed, both as Nomad services or as a stand-alone application. The only requirement is access to API of consul servers, and Nomad services ServicePort & ServiceAddress

Below is minimal upstreams file for Consul.

provider: "consul"
sticky_sessions: 172000
to_https: false
rate_limit: 500000
x4xx_limit: 100000
server_headers:
  - "X-Global-For-Servers:Something"
client_headers:
  - "X-Global-For-Clients:Something"
#authorization:
#  type: "basic"
#  data: "root:toor"
#  type: "jwt"
#  data: "910517d9-f9a1-48de-8826-dbadacbd84af-cb6f830e-ab16-47ec-9d8f-0090de732774"
#    type: "apikey"
#    data: "5ecbf799-1343-4e94-a9b5-e278af5cd313-56b45249-1839-4008-a450-a60dc76d2bae"
consul:
  servers:
    - "http://consul1:8500"
    - "http://consul2:8500"
    - "http://consul3:8500"
  token: "8e2db809-845b-45e1-8b47-2c8356a09da0-a4370955-18c2-4d6e-a8f8-ffcc0b47be81" # Consul server access token, If Consul auth is enabled

The rest of configuration parameters Aralez will take and periodically update from Consul’s API

Deploying service

configuration of upstreams is done trough TAGs in nomad job definition in format aralez.key=value.
In order to filter services, Aralez will query Consul for services with hardcoded tag aralez.service=yes. Only services with this tag will be configured as upstreams. 2 more mandatory tags for services are required. "aralez.host=your.example.com" and "aralez.path=/". To populate configure internal routing .

All other parameters, as with file config parameter are optional .

Minimal tags in Nomad job definition file. :

 tags = [
    "aralez.service=yes",
    "aralez.host=nginx.blablabla.com",
    "aralez.path=/",
]

Full list of supported tags.

tags = [
    "aralez.service=yes",
    "aralez.host=nginx.example.com",
    "aralez.path=/",
    
    "aralez.rate=1",
    "aralez.4xx_rate=10",
    "aralez.to_https=true",
    "aralez.client_header=X-Some:Some Random Header",
    "aralez.client_header=X-Emos:Redaeh Modnar Emos",
    "aralez.server_header=X-From:Aralez & Consul",
    "aralez.server_header=X-Mrof: Lusnoc & Zelara",
]

You can duplicate as many as neede aralez.client_header & aralez.server_header keys . All values after = will be applied as client/server side headers.

Full Example of a Nomad job definition file, used for internal testing.

job "nginx" {
  meta {
    uuid = uuidv4()
  }
  datacenters = ["eu-ams-1"]
  type = "service"
  constraint {
    attribute = node.unique.name
    operator  = "regexp"
    value     = "consul[0-9]"
  }
  update {
    max_parallel      = 1
    min_healthy_time  = "10s"
    healthy_deadline  = "3m"
    progress_deadline = "10m"
    auto_revert       = false
    canary            = 0
  }
  migrate {
    max_parallel     = 1
    health_check     = "checks"
    min_healthy_time = "10s"
    healthy_deadline = "5m"
  }
  group "NginX" {
    network {
      port "nginx" { to = 80 }
    }
    constraint {
      operator = "distinct_hosts"
      value    = "true"
    }
    count = 3
    restart {
      attempts = 2
      interval = "30m"
      delay    = "15s"
      mode     = "fail"
    }
    task "server" {
      service {
        port = "nginx"
        tags = [
          "aralez.service=yes",
          "aralez.host=nginx.example.com",
          "aralez.path=/",
          "aralez.rate=10",
          "aralez.4xx_rate=5",
          "aralez.to_https=true",
          "aralez.client_header=X-Some:Some Random Header",
          "aralez.client_header=X-Emos:Redaeh Modnar Emos",
          "aralez.server_header=X-From:Aralez & Consul",
          "aralez.server_header=X-Mrof: Lusnoc & Zelara",
        ]
        check {
          type     = "http"
          port     = "nginx"
          path     = "/"
          interval = "5s"
          timeout  = "2s"
        }
      }
      driver = "docker"
      config {
        image      = "nginx:latest"
        force_pull = true
        ports = ["nginx"]
      }
    }
  }
}

This will:

Here: are some more Nomad job definition files