feat: adding the ability source the username from the configuration (#5)

README.md

@@ -36,6 +36,18 @@ The `terraform-docs` utility is used to generate this README. Follow the below s
 2. Fetch the `terraform-docs` binary (https://terraform-docs.io/user-guide/installation/)
 3. Run `terraform-docs markdown table --output-file ${PWD}/README.md --output-mode inject .`
 
+## Using Secrets Manager
+
+The `slack` configuration can be sourced from AWS Secrets Manager, using the `var.slack.secret_name`. The secret should be a JSON object reassembling the `slack` configuration.
+
+```json
+{
+  "channel": "#channel",
+  "username": "username",
+  "webhook_url": "https://hooks.slack.com/services/..."
+}
+```
+
 <!-- BEGIN_TF_DOCS -->
 ## Requirements
 

locals.tf

@@ -22,4 +22,6 @@ locals {
   slack_webhook_url = local.enable_slack_secret ? jsondecode(data.aws_secretsmanager_secret_version.slack[0].secret_string)["webhook_url"] : try(var.slack.webhook_url, null)
   ## The slack channel to post to 
   slack_channel = local.enable_slack_secret ? jsondecode(data.aws_secretsmanager_secret_version.slack[0].secret_string)["channel"] : try(var.slack.channel, null)
+  ## slack_username to use  
+  slack_username = local.enable_slack_secret ? jsondecode(data.aws_secretsmanager_secret_version.slack[0].secret_string)["username"] : try(var.slack.username, null)
 }

main.tf

@@ -47,7 +47,7 @@ module "slack" {
   lambda_function_tags     = var.tags
   recreate_missing_package = false
   slack_channel            = local.slack_channel
-  slack_username           = var.slack.username
+  slack_username           = local.slack_username
   slack_webhook_url        = local.slack_webhook_url
   sns_topic_name           = var.sns_topic_name
   tags                     = var.tags