This guide helps you to get Backstage up and running with Nomad. It's inspired from Deploying with Kubernetes guide.
This example is not for production deployment!
Deployments in Nomad are commonly assigned to their own namespace to isolate services in a multi-tenant environment.
This can be done through Nomad CLI directly:
nomad namespace apply backstage
First, create a Nomad Variable for the PostgreSQL username and password. This will be used by both the PostgreSQL database and Backstage deployments:
# postgres.nv.hcl
path = "nomad/jobs"
namespace = "backstage"
items {
postgres_user = "YmFja3N0YWdl"
postgres_password = "aHVudGVyMg=="
}
The secrets can now be applied to Nomad:
nomad var put @postgres.nv.hclIn order to persist PostgreSQL data we will create a host volume, maybe in a production scenario a CSI volume will be more appropriate. Modify the configuration file of the client node as follow:
# config.hcl
client {
host_volume "postgres" {
path = "/mnt/data"
read_only = false
}
}
Now we can create a Nomad job for the PostgreSQL database deployment itself:
# postgres.hcl
job "postgres" {
datacenters = ["dc1"]
namespace = "backstage"
type = "service"
group "backstage-db" {
count = 1
network {
mode = "host"
port "db" {
static = 5432
to = 5432
}
}
volume "postgres" {
type = "host"
read_only = false
source = "postgres"
}
task "backstage-db" {
service {
name = "database"
provider = "nomad"
port = "db"
}
volume_mount {
volume = "postgres"
destination = "/var/lib/postgresql/data"
read_only = false
}
driver = "docker"
config {
image = "postgres:13.2-alpine"
ports = ["db"]
}
template {
destination = "${NOMAD_SECRETS_DIR}/env.vars"
env = true
change_mode = "restart"
data = <<EOF
{{- with nomadVar "nomad/jobs" -}}
POSTGRES_USER = {{ .postgres_user }}
POSTGRES_PASSWORD = {{ .postgres_password }}
{{- end -}}
EOF
}
}
}
}
Apply the PostgreSQL deployment to the Kubernetes cluster:
$ nomad run postgres.hcl
$ nomad job status -namespace=backstage
ID Type Priority Status Submit Date
postgres service 50 running 2022-10-28T21:35:15-04:00
Now that we have PostgreSQL up and ready to store data, we can create the Backstage instance. This follows similar steps as the PostgreSQL deployment.
For any Backstage configuration secrets, such as authorization tokens, we can create a similar Nomad Variable as we did for PostgreSQL:
# backstage.nv.hcl
path = "nomad/jobs/backstage"
namespace = "backstage"
items {
github_token = "VG9rZW5Ub2tlblRva2VuVG9rZW5NYWxrb3ZpY2hUb2tlbg=="
}
The secrets can now be applied to Nomad:
nomad var put @backstage.nv.hclTo create the Backstage deployment, first create a Docker image. We'll use this image to create a Nomad job. For this example, we'll use the standard host build with the frontend bundled and served from the backend.
First, create a Nomad job file:
# backstage.hcl
job "backstage" {
datacenters = ["dc1"]
namespace = "backstage"
type = "service"
group "backstage-svc" {
count = 1
network {
mode = "host"
port "http" {
to = 7007
}
}
task "backstage-backend" {
service {
name = "database"
provider = "nomad"
port = "http"
}
driver = "docker"
config {
image = "backstage:1.0.0"
ports = ["http"]
}
template {
data = <<EOH
{{ range nomadService "database" }}
POSTGRES_SERVICE_HOST="{{ .Address }}"
POSTGRES_SERVICE_PORT="{{ .Port }}"
{{ end }}
EOH
destination = "local/env.txt"
env = true
}
template {
destination = "${NOMAD_SECRETS_DIR}/env.vars"
env = true
change_mode = "restart"
data = <<EOF
{{- with nomadVar "nomad/jobs" -}}
POSTGRES_USER = {{ .postgres_user }}
POSTGRES_PASSWORD = {{ .postgres_password }}
{{- end -}}
EOF
}
template {
destination = "${NOMAD_SECRETS_DIR}/env2.vars"
env = true
change_mode = "restart"
data = <<EOF
{{- with nomadVar "nomad/jobs/backstage" -}}
GITHUB_TOKEN = {{ .github_token }}
{{- end -}}
EOF
}
}
}
}