Simple Service

This pack is a used to deploy a Docker image to as a service job to Nomad.

This is ideal for configuring and deploying a simple web application to Nomad.

Customizing the Docker Image

The docker image deployed can be replaced with a variable. In the example below, we will deploy and run httpd:latest.

nomad-pack run simple_service --var image="httpd:latest"

Customizing Ports

The ports that are exposed via Docker can be customized as well.

In this case, we'll write the port values to a file called ./overrides.hcl:

{
  name = "http"
  port = 8000
},
{
  name = "https"
  port = 8001
}

Then pass the file into the run command:

nomad-pack run simple_service -f ./overrides.hcl`"

Customizing Resources

The application resource limits can be customized:

resources = {
  cpu = 500
  memory = 501
}

Customizing Environment Variables

Environment variables can be added:

env_vars = [
  {
    key = "foo"
    value = 1
  }
]

Consul Service and Load Balancer Integration

Optionally, this pack can configure a Consul service.

If the register_consul_service is unset or set to true, the Consul service will be registered.

Several load balancers in the The Nomad Pack Community Registry are configured to connect to this service with ease.

The NginX and HAProxy packs can be configured to balance over the Consul service deployed by this pack. Just ensure that the "consul_service_name" variable provided to those packs matches this consul_service_name.

The Fabio and Traefik packs are configured to search for Consul services with the specific tags.

To tag this Consul service to work with Fabio, add "urlprefix-<PATH>" to the consul_tags. For instance, to route at the root path, you would add "urlprefix-/". To route at the path "/api/v1", you would add '"urlprefix-/api/v1".

To tag this Consul service to work with Traefik, add "traefik.enable=true" to the consul_tags, also add "traefik.http.routers.http.rule=Path(``)". To route at the root path, you would add "traefik.http.routers.http.rule=Path(`/`)". To route at the path "/api/v1", you would add "traefik.http.routers.http.rule=Path(`/api/v1`)".

register_consul_service = true
 
consul_tags = [
  "urlprefix-/",
  "traefik.enable=true",
  "traefik.http.routers.http.rule=Path(`/`)",
]

Customizing Consul and Upstream Services

Consul configuration can be tweaked and (upstream services)[https://www.nomadproject.io/docs/job-specification/upstreams] can be added as well.

register_consul_service = true
consul_service_name = "app-service-name"
has_health_check = true
health_check = {
  path = "/health"
  interval = "20s"
  timeout  = "3s"
}
upstreams = [
  {
    name = "other-service"
    port = 8001
  }
]