feat: Adding the Terraform module

.github/workflows/terraform.yaml

@@ -0,0 +1,30 @@
+name: Check the Terraform Module
+
+on:
+  pull_request:
+    paths:
+      - '**.tf'
+
+jobs:
+  build:
+    name: Terraform Checks and Plans
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the repository to the runner
+        uses: actions/checkout@v3
+
+      - name: HashiCorp - Setup Terraform
+        uses: hashicorp/setup-terraform@v3
+
+      - name: Terraform Format
+        id: fmt
+        run: terraform fmt -recursive -check
+        continue-on-error: true
+
+      - name: Terraform Init
+        id: init
+        run: terraform init
+
+      - name: Terraform Validate
+        id: validate
+        run: terraform validate -no-color

.gitignore

@@ -1,10 +1,55 @@
+*.idea
+.vscode/
+.coverage
+.tox/
 venv/
 build/
-*.charm
-.coverage
+tests/integration/*-tester/lib/
+
+# Python
+**/venv/**
+*.pyc
+.python-version
+.mypy_cache/
 __pycache__/
 *.py[cod]
-.tox
-.idea/
-tests/integration/*-tester/lib/
-.env
+
+# Charmcraft
+*.charm
+
+# Local .terraform directories
+**/.terraform/*
+
+# .tfstate files
+*.tfstate
+*.tfstate.*
+
+# Crash log files
+crash.log
+crash.*.log
+
+# Exclude all .tfvars files, which are likely to contain sensitive data, such as
+# password, private keys, and other secrets. These should not be part of version
+# control as they are data points which are potentially sensitive and subject
+# to change depending on the environment.
+*.tfvars
+*.tfvars.json
+
+# Ignore override files as they are usually used to override resources locally and so
+# are not checked in
+override.tf
+override.tf.json
+*_override.tf
+*_override.tf.json
+
+# Include override files you do wish to add to version control using negated pattern
+# !example_override.tf
+
+# Include tfplan files to ignore the plan output of command: terraform plan -out=tfplan
+# example: *tfplan*
+
+# Ignore CLI configuration files
+.terraformrc
+terraform.rc
+.terraform.lock.hcl
+

terraform/README.md

@@ -0,0 +1,65 @@
+# Grafana-agent-k8s Terraform Module
+
+This Grafana-agent-k8s Terraform module aims to deploy the [grafana-agent-k8s charm](https://charmhub.io/grafana-agent-k8s) via Terraform.
+
+## Getting Started
+
+### Prerequisites
+
+The following software and tools needs to be installed and should be running in the local environment. Please [set up your environment](https://discourse.charmhub.io/t/set-up-your-development-environment-with-microk8s-for-juju-terraform-provider/13109) before deployment.
+
+- `microk8s`
+- `juju 3.x`
+- `terrafom`
+
+### Module structure
+
+- **main.tf** - Defines the Juju application to be deployed.
+- **variables.tf** - Allows customization of the deployment. Except for exposing the deployment options (Juju model name, channel or application name) also models the charm configuration.
+- **output.tf** - Responsible for integrating the module with other Terraform modules, primarily by defining potential integration endpoints (charm integrations), but also by exposing the application name.
+- **terraform.tf** - Defines the Terraform provider.
+
+## Using Grafana-agent-k8s base module in higher level modules
+
+If you want to use `grafana-agent-k8s` base module as part of your Terraform module, import it like shown below.
+
+```text
+module "grafana-agent-k8s" {
+  source = "git::https://github.com/canonical/grafana-agent-k8s-operator//terraform"
+
+  model_name = "juju_model_name"
+  # Optional Configurations
+  # channel                        = "put the Charm channel here" 
+  # grafana-config = {
+  #   tls_insecure_skip_verify = "put True not to skip the TLS verification"
+  # }
+}
+```
+
+Please see the link to customize the Grafana configuration variables if needed.
+
+- [Grafana configuration option](https://charmhub.io/grafana-agent-k8s/configure)
+
+Create the integrations, for instance:
+
+```text
+resource "juju_integration" "amf-metrics" {
+  model = var.model_name
+
+  application {
+    name     = module.amf.app_name
+    endpoint = module.grafana.metrics_endpoint
+  }
+
+  application {
+    name     = module.grafana.app_name
+    endpoint = module.grafana.metrics_endpoint
+  }
+}
+```
+
+Please check the available [integration pairs](https://charmhub.io/grafana-agent-k8s/integrations).
+
+[Terraform](https://www.terraform.io/)
+
+[Terraform Juju provider](https://registry.terraform.io/providers/juju/juju/latest)

terraform/main.tf

@@ -0,0 +1,16 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+resource "juju_application" "grafana-agent-k8s" {
+  name  = var.app_name
+  model = var.model_name
+
+  charm {
+    name    = "grafana-agent-k8s"
+    channel = var.channel
+  }
+  config = var.grafana_config
+  units  = 1
+  trust  = true
+}
+

terraform/outputs.tf

@@ -0,0 +1,52 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+output "app_name" {
+  description = "Name of the deployed application."
+  value       = juju_application.grafana-agent-k8s.name
+}
+
+output "certificates_endpoint" {
+  description = "Name of the endpoint to get the X.509 certificate using tls-certificates interface."
+  value       = "certificates"
+}
+
+output "send_remote_write_endpoint" {
+  description = "Name of the endpoint to forward client charms metrics and associated alert rules to Prometheus using prometheus_remote_write interface."
+  value       = "send-remote-write"
+}
+
+output "metrics_endpoint" {
+  description = "Name of the endpoint to expose the Prometheus metrics endpoint providing telemetry about the Grafana instance using prometheus_scrape interface."
+  value       = "metrics-endpoint"
+}
+
+output "logging_consumer_endpoint" {
+  description = "Name of the endpoint to send the logs to Loki using loki_push_api interface."
+  value       = "logging-consumer"
+}
+
+output "grafana_dashboards_consumer_endpoint" {
+  description = "Name of the endpoint to provide meaningful dashboards about it's metrics using grafana_dashboard interface."
+  value       = "grafana-dashboards-consumer"
+}
+
+output "grafana_cloud_config_endpoint" {
+  description = "Name of the endpoint to forward telemetry to any Prometheus(or Loki) compatible endpoint using grafana_cloud_config interface."
+  value       = "grafana-cloud-config"
+}
+
+output "receive_ca_cert_endpoint" {
+  description = "Name of the endpoint to get the Self signed X.509 Certificates through the relation with Self Signed Certificates Charm using certificate_transfer interface."
+  value       = "receive-ca-cert"
+}
+
+output "logging_provider_endpoint" {
+  description = "Name of the endpoint provided by Grafana to receive logs from any charm that supports the loki_push_api relation interface."
+  value       = "logging-provider"
+}
+
+output "grafana_dashboards_provider_endpoint" {
+  description = "Name of the endpoint provided by Grafana to provide meaningful dashboards about its metrics to be shown in a Grafana Charm over the grafana-dashboard relation using the grafana-dashboard interface."
+  value       = "grafana-dashboards-provider"
+}

terraform/terraform.tf

@@ -0,0 +1,11 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+terraform {
+  required_providers {
+    juju = {
+      source  = "juju/juju"
+      version = "~> 0.10.1"
+    }
+  }
+}

terraform/variables.tf

@@ -0,0 +1,25 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+variable "model_name" {
+  description = "Name of Juju model to deploy application to"
+  type        = string
+  default     = ""
+}
+
+variable "app_name" {
+  description = "Name of the application in the Juju model"
+  type        = string
+  default     = "grafana"
+}
+
+variable "channel" {
+  description = "The channel to use when deploying a charm "
+  type        = string
+  default     = "latest/stable"
+}
+
+variable "grafana_config" {
+  description = "Additional configurations for the Grafana. Please see the available options: https://charmhub.io/grafana-agent-k8s/configure"
+  default     = {}
+}