docs(mnq): Guide to set up Messaging configuration and Terraform NATS (#1696)

Author: Monitob

docs/guides/mnq_with_nats_terraform_provider.md

@@ -0,0 +1,122 @@
+---
+page_title: "Using Scaleway Messaging and Queuing service with NATS Terraform provider"
+description: |-
+Using Scaleway Messaging and Queuing service with NATS Terraform provider
+---
+
+# How to use Scaleway Messaging and Queuing config
+
+This guide shows the combination of Scaleway Messaging and Queuing configuration with to terraform NATS Jetstream
+provider. Il will allow you to provision and manage NATS Jetstream resources.
+
+At the end of this guide, you will have a running NATS server and a configured NATS CLI to interact with it.
+
+## Prerequisites
+
+* First, you will need to set up a new Terraform configuration file
+  with [Scaleway](https://registry.terraform.io/providers/scaleway/scaleway/latest/docs/resources/mnq_namespace)
+  and [Jetstream provider](https://registry.terraform.io/providers/nats-io/jetstream/latest/docs/guides/setup).
+
+```hcl
+terraform {
+  required_providers {
+    scaleway = {
+      source = "scaleway/scaleway"
+    }
+    jetstream = {
+      source  = "nats-io/jetstream"
+      version = "~> 0.0.34"
+    }
+  }
+}
+
+provider "scaleway" {
+  region     = "fr-par"
+  access_key = "<SCW_ACCESS_KEY>"
+  secret_key = "<SCW_SECRET_KEY>"
+  project_id = "<SCW_DEFAULT_PROJECT_ID>"
+}
+```
+
+* Next, you should create a Messaging and Queuing namespace. Check our example below.
+
+```hcl
+resource "scaleway_mnq_namespace" "main" {
+  name     = "mnq-ns"
+  protocol = "nats"
+}
+```
+
+* Before creating your credentials, be aware that due to an
+  ongoing [issue](https://github.com/hashicorp/terraform/issues/516) since 2014, secrets stored in `terraform.tfstate`
+  remain in plain text. While there are methods to remove secrets from state files, they are unreliable and may not
+  function properly with updates to Terraform. It is not recommended to use these workarounds.
+
+---
+
+* Otherwise, the official update on December3, 2020:
+  Terraform 0.14 has added the ability to mark variables as sensitive, which helps keep them out of your logs, so you
+  should add `sensitive = true` to variables!
+
+---
+
+* You can create Credentials easily using the Scaleway provider.
+  Check our example below and more about authenticating with a Credentials
+  File [here](https://docs.nats.io/using-nats/developer/connecting/creds)
+
+```hcl
+resource "scaleway_mnq_credential" "main" {
+  name         = "creds-ns"
+  namespace_id = scaleway_mnq_namespace.main.id
+}
+```
+
+* At this point you have your Namespace and your Credential that means you have a running NATS Server ready to be used.
+
+* Grab a copy of the [NATS CLI](https://github.com/nats-io/jetstream/releases) and configure it with your
+  endpoint. To be practical let's use `contexts` that you can store and easily select the relevant context. Check more
+  details [here](https://docs.nats.io/using-nats/nats-tools/nats_cli#configuration-contexts).
+
+```shell
+nats context save example --server nats://nats.mnq.fr-par.scw.cloud:4222 --description 'Prod.Net Server'
+```
+
+* The output should look like this:
+
+```shell
+NATS Configuration Context "example"
+
+      Description: Prod.Net Server
+      Server URLs: nats://nats.mnq.fr-par.scw.cloud:4222
+             Path: /Your/path/context/example.json
+```
+
+* Try to select your configuration using the NATS CLI:
+
+```shell
+nats context select
+? Select a Context  [Use arrows to move, type to filter]
+> example
+```
+
+* Finally, configure the CLI with the namespace credentials.
+
+```shell
+NATS Configuration Context "example"
+
+      Description: Prod.Net Server
+      Server URLs: nats://nats.mnq.fr-par.scw.cloud:4222
+      Credentials: /Your/path/secret/admin.creds (OK)
+             Path: /Your/path/context/example.json
+```
+
+* You are ready to use the
+  NATS [JetStream Provider](https://registry.terraform.io/providers/nats-io/jetstream/latest/docs):
+
+```hcl
+provider "jetstream" {
+  servers     = scaleway_mnq_namespace.manin.endpoint
+  credentials = "path/ngs_stream_admin.creds"
+  # credential_data = "<SCW_CREDENTIAL_AS_STRING>"
+}
+```