Developing Real-time resource monitoring via email on AWS using Terraform | by krishna dutt | Feb, 2022

Save the price of monitoring utilizing this system

One of many essential duties as an SRE engineer is to keep up the infrastructure that’s developed for the deployment of the applying. As every of the service exposes the logs in several method, we want plethora of sns and lambdas to observe the infrastructure. This will increase the price of monitoring, which might compel administration to drop this monitoring system.

However what if i say that, we will develop this monitoring system for lower than 24 cents ? And what if i say you can deploy this whole monitoring system with only a single command “Terraform apply”? Seems like one thing that you just wish to know? Hop on the Terraform trip !

Key parts to construct the infrastructure

To be able to create an monitoring system to ship e-mail alerts, we want 3 parts:

1. Occasion Bridge
2. SNS
3. Electronic mail subscription

We will construct a rudimentary monitoring system, by combining all these parts. However the logs we get as e-mail, could be as following:

{“model”:”1.0",”timestamp”:”2022–02–01T12:58:45.181Z”,”requestContext”:“requestId”:”a4ac706f-1aea-4b1d-a6d2–5e6bb58c4f3e”,”functionArn”:”arn:aws:lambda:ap-south-1:498830417177:operate:gggg:$LATEST”,”situation”:”Success”,”approximateInvokeCount”:1,”requestPayload”:{“Data”:[“eventVersion”:”2.1",”eventSource”:”aws:s3",”awsRegion”:”ap-south-1",”eventTime”:”2022–02–01T12:58:43.330Z”,”eventName”:”ObjectCreated:Put”,”userIdentity”:“principalId”:”A341B33DQLH0UH”,”requestParameters”:“sourceIPAddress”:”43.241.67.169",”responseElements”:“x-amz-request-id”:”GX86AGXCNXB5ZYVQ”,”x-amz-id-2":”CPVpR8MNcPsNBzxcF8nOFqXbAIU60/zQlNC6njLp+wNFtC/ZnZF0SFhfMuhLOSpEqMFvvPqLA+tyvaXJSYMXAByR5EuDM0VF”,”s3":“s3SchemaVersion”:”1.0",”configurationId”:”09dae0eb-9352–4d8a-964f-1026c76a5dcc”,”bucket”:“name”:”sddsdsbbb”,”ownerIdentity”:“principalId”:”A341B33DQLH0UH”,”arn”:”arn:aws:s3:::sddsdsbbb”,”object”:“key”:”variables.tf”,”size”:402,”eTag”:”09ba37f25be43729dc12f2b01a32b8e8",”sequencer”:”0061F92E834A4ECD4B”]},”responseContext”:“statusCode”:200,”executedVersion”:”$LATEST”,”responsePayload”:”binary/octet-stream”}

Not really easy to learn proper ? What if we will enhance it, making it legible for anybody to grasp what is going on?

To make it simple to learn, we use the characteristic within the Occasion bridge referred to as enter transformer and enter template. This characteristic helps us in reworking the log in our desired format with out utilizing any lambda operate.

The way in which our infrastructure works is as follows:

1. Our occasion bridge will gather all of the logs from all of the occasions from the AWS account, utilizing occasion filter.

2. As soon as collected, these are despatched to enter transformer to parse and skim our desired parts.

3. After this, we use this parsed information to create our desired format utilizing enter template.

4. This reworked information is printed to the SNS that we now have created.

5. We create a subscription for this SNS, by way of e-mail,SMS or HTTP.

And Voila ! you could have your infrastructure able to replace the adjustments…!

Right here is the whole terraform code:

terraform 
required_providers 
aws = 
supply  = "hashicorp/aws"
model = "~> 3.0"


# Configure the AWS Supplier
supplier "aws" 
area = "ap-south-1" #insert your area code
useful resource "aws_cloudwatch_event_rule" "eventtosns" 
identify = "eventtosns"
event_pattern = jsonencode(

account = [
var.account,#insert  your account number
]

)useful resource "aws_cloudwatch_event_target" "eventtosns" # arn of the goal and rule id of the eventrule
arn  = aws_sns_topic.eventtosns.arn
rule = aws_cloudwatch_event_rule.eventtosns.idinput_transformer 
input_paths = 
Supply      = "$.supply",
detail-type = "$.detail-type",
assets   = "$.assets",
state       = "$.element.state",
standing      = "$.element.standing"

input_template = ""Useful resource identify : <Supply> , Motion identify : <detail-type>,
particulars : <standing> <state>, Arn : <assets>""

useful resource "aws_sns_topic" "eventtosns" 
identify = "eventtosns"
useful resource "aws_sns_topic_subscription" "snstoemail_email-target" 
topic_arn = aws_sns_topic.eventtosns.arn
protocol  = "e-mail"
endpoint  = var.e-mail
# aws_sns_topic_policy.eventtosns:
useful resource "aws_sns_topic_policy" "eventtosns" 
arn = aws_sns_topic.eventtosns.arncoverage = jsonencode(

Id = "default_policy_ID"
Assertion = [

Action = [
"SNS:GetTopicAttributes",
"SNS:SetTopicAttributes",
"SNS:AddPermission",
"SNS:RemovePermission",
"SNS:DeleteTopic",
"SNS:Subscribe",
"SNS:ListSubscriptionsByTopic",
"SNS:Publish",
"SNS:Receive",
]
situation = 
check     = "StringEquals"
variable = "AWS:SourceOwner"
values = [
var.account,
]
Impact = "Enable"
Principal = 
AWS = "*"

Useful resource = aws_sns_topic.eventtosns.arn
Sid      = "__default_statement_ID"
,

Motion = "sns:Publish"
Impact = "Enable"
Principal = 
Service = "occasions.amazonaws.com"

Useful resource = aws_sns_topic.eventtosns.arn
Sid      = "AWSEvents_lambdaless_Idcb618e86-b782-4e67-b507-8d10aaca5f09"
,
]
Model = "2008-10-17"

)

This complete infrastructure may be deployed utilizing Terraform apply on above code.