Start container without any servers running

* If SERVER_TYPE environment variable is set 'none' for the docker container, it will run without starting any server

Author: bogsi17

.github/workflows/deploy-data-replica.yml

@@ -8,7 +8,10 @@ if [ "$SERVER_TYPE" == "web" ]; then
 elif [ "$SERVER_TYPE" == "good-job" ]; then
   echo "Starting good-job server..."
   exec "$BIN_DIR"/good_job start
+elif [ "$SERVER_TYPE" == "none" ]; then
+  echo "No server started"
+  exec tail -f /dev/null  # Keep container running
 else
-  echo "SERVER_TYPE variable: '$SERVER_TYPE' unknown. Allowed values ['web','good-job']"
+  echo "SERVER_TYPE variable: '$SERVER_TYPE' unknown. Allowed values ['web','good-job', 'none']"
   exit 1
 fi

bin/docker-start

@@ -10,7 +10,7 @@ resource "aws_appautoscaling_target" "this" {
 
 resource "aws_appautoscaling_policy" "this" {
   for_each           = local.autoscaling_enabled ? var.autoscaling_policies : {}
-  name               = "${var.server_type}-${each.key}-scaling-${var.environment}"
+  name               = "${local.server_type_name}-${each.key}-scaling-${var.environment}"
   policy_type        = "TargetTrackingScaling"
   resource_id        = aws_appautoscaling_target.this[0].resource_id
   scalable_dimension = aws_appautoscaling_target.this[0].scalable_dimension

terraform/app/modules/ecs_service/autoscaling.tf

@@ -9,7 +9,7 @@ terraform {
 }
 
 resource "aws_security_group" "this" {
-  name        = "${var.server_type}-service-${var.environment}"
+  name        = "${local.server_type_name}-service-${var.environment}"
   description = "Security Group for communication with ECS Service"
   vpc_id      = var.network_params.vpc_id
   lifecycle {
@@ -27,7 +27,7 @@ resource "aws_security_group_rule" "egress_all" {
 }
 
 resource "aws_ecs_service" "this" {
-  name                              = "${var.naming_prefix}${var.environment}-${var.server_type}"
+  name                              = "mavis-${var.environment}-${local.server_type_name}"
   cluster                           = var.cluster_id
   task_definition                   = aws_ecs_task_definition.this.arn
   desired_count                     = var.minimum_replica_count
@@ -70,7 +70,7 @@ resource "aws_ecs_service" "this" {
 }
 
 resource "aws_ecs_task_definition" "this" {
-  family                   = "${var.naming_prefix}${var.server_type}-task-definition-${var.environment}"
+  family                   = "mavis-${local.server_type_name}-task-definition-${var.environment}"
   requires_compatibilities = ["FARGATE"]
   network_mode             = "awsvpc"
   cpu                      = var.task_config.cpu
@@ -95,7 +95,7 @@ resource "aws_ecs_task_definition" "this" {
         options = {
           awslogs-group         = var.task_config.log_group_name
           awslogs-region        = var.task_config.region
-          awslogs-stream-prefix = "${var.environment}-${var.server_type}-logs"
+          awslogs-stream-prefix = "${var.environment}-${local.server_type_name}-logs"
         }
       }
       healthCheck = {

terraform/app/modules/ecs_service/main.tf

@@ -6,10 +6,17 @@ variable "environment" {
 
 variable "server_type" {
   type        = string
-  description = "Type of server to be deployed. This is set as an environment variable in the main container, and is used to determine how the application is launched"
+  description = "Type of server to be deployed. This is set as an environment variable in the main container, and is used to determine how the application is launched."
   nullable    = false
 }
 
+variable "server_type_name" {
+  type        = string
+  description = "Name of the server type to be deployed."
+  default     = null
+  nullable    = true
+}
+
 variable "minimum_replica_count" {
   type        = number
   description = "Minimum amount of allowed replicas for the service. Also the replica count when creating th service."
@@ -26,13 +33,6 @@ variable "maximum_replica_count" {
   }
 }
 
-variable "naming_prefix" {
-  type        = string
-  description = "Prefix to be used for naming the ECS service and task definition"
-  default     = "mavis-"
-  nullable    = false
-}
-
 variable "autoscaling_policies" {
   type = map(object({
     predefined_metric_type = string
@@ -116,4 +116,5 @@ variable "container_name" {
 
 locals {
   autoscaling_enabled = var.maximum_replica_count > var.minimum_replica_count
+  server_type_name    = var.server_type_name != null ? var.server_type_name : var.server_type
 }

terraform/app/modules/ecs_service/variables.tf

@@ -0,0 +1,32 @@
+# Data replication module
+
+## Overview
+
+This module can be used to verify data migration tasks on a copy of actual production data before running them on production.
+
+It creates
+
+- A replication of a given database based on a provided snapshot
+- A dedicated ECS service connected to the database
+
+## Setup
+
+This module is managed via a GitHub Actions workflow. To separate it from the rest of the infrastructure, the workflow uses a dedicated IAM role. To set up everything from scratch, manually create the role
+`GithubDeployDataReplicationInfrastructure` based on the policy template `github_data_replication_actions_policy.json` and the trust policy `github_role_<ENVIRONMENT>_trust_policy.json`.
+
+## Usage
+
+### Manage the database replication infrastructure
+
+To create the infrastructure, run the `data-replication-pipeline.yml` workflow and select the 'Recreate' option.
+This will destroy any existing replication infrastructure and create a new replicated database from the latest snapshot.
+
+To destroy the resources, run the `data-replication-pipeline.yml` with the 'Destroy' option.
+
+### Connect to the dedicated ECS task
+
+To connect to the dedicated ECS task, run
+
+```
+./script/shell.sh <ENV>-data-replication
+```

terraform/data_replication/README.md

@@ -10,7 +10,7 @@ resource "aws_ecs_cluster" "cluster" {
 
 resource "aws_cloudwatch_log_group" "ecs_log_group" {
   name              = "${local.name_prefix}-ecs"
-  retention_in_days = 1
+  retention_in_days = 14
   skip_destroy      = false
 }
 
@@ -20,14 +20,14 @@ module "db_access_service" {
   cluster_id            = aws_ecs_cluster.cluster.id
   cluster_name          = aws_ecs_cluster.cluster.name
   environment           = var.environment
-  naming_prefix         = "mavis-data-replication-"
   maximum_replica_count = 1
   minimum_replica_count = 1
   network_params = {
     subnets = local.subnet_list
     vpc_id  = aws_vpc.vpc.id
   }
-  server_type = "good-job"
+  server_type      = "none"
+  server_type_name = "data-replication"
   task_config = {
     environment          = local.task_envs
     secrets              = local.task_secrets
@@ -38,7 +38,7 @@ module "db_access_service" {
     task_role_arn        = aws_iam_role.ecs_task_role.arn
     log_group_name       = aws_cloudwatch_log_group.ecs_log_group.name
     region               = var.region
-    health_check_command = ["CMD-SHELL", "curl -f http://localhost:4000 || exit 1"]
+    health_check_command = ["CMD-SHELL", "echo 'alive' || exit 1"]
   }
   depends_on = [aws_rds_cluster_instance.instance]
 }