peterolayinka/mailgun-webhook-processor

MailGun WebHook Processor

Setup Guide

The resources beolow are required for a successful deployment of this code to AWS manually, but you can use the cloudformation template in the repo for a quick and easy setup.

• Login to AWS
• Create IAM role
  • attach policies (Cloudwatch, SNS, S3, etc..) and neccessary permission
• Create SNS Topic
• Create S3 bucket for storage
• Create API Gateway (REST API)
  • Create POST method
  • Lambda Invocation
  • Enable Lambda Proxy Integration
  • Add the role above to the lambda function
  • Create environment variables as seen in .env.example file
  • Create model to reduce invalid request sent to Lambda
  • click method request to add the new model to request body and set request validator to validate body, query string and headers

Setup with cloudformation

• Login to AWS
• Search and open the cloudformation service
• click on create stack
• select the cloudformation template in this repo
• enter the neccessary paramters as you deem fit
• change the email paramter to an email you control to verify the notification service is working as expected
• continue clicking the next button until the stack creation process starts.
• Refresh the page and click on output to see the API Gateway URL created.
• run npm install to install dependencies
• run npm build to build the project
• copy the index.js file content and paste in the lambda function code section
• Note The lambda function can be seen in the resources tab in cloudformation
• click deploy on the lambda function
• VOILA!
• You can now test the endpoint seen in the output section.
• Ensure to change the event id for multiple test
• Verify you got the email from SNS
• Verify the data is stored in the created S3

Sample payload to test API endpoint

  {
    "signature":
    {
      "timestamp": "1529006854",
      "token": "a8ce0edb2dd8301dee6c2405235584e45aa91d1e9f979f3de0",
      "signature": "50dd7709613e688fd1e2c445b680b1948fe09ea315d472df2c6c8db88154902b"
    },
    "event-data":
    {
      "event": "opened",
      "timestamp": 1529006854.329574,
      "id": "DACSsAdVSeGpLid7TN03WA"
    }
  }

Snippet to generate valid mailgun signature

Please see the test signingKey in the example evnironment file

  const encodedToken = crypto
      .createHmac("sha256", signingKey)
      .update(timestamp.concat(token))
      .digest("hex");

Sample Payload to test Lambda Function

  {
    "resource": "/",
    "path": "/",
    "httpMethod": "POST",
    "headers": null,
    "multiValueHeaders": null,
    "queryStringParameters": null,
    "multiValueQueryStringParameters": null,
    "pathParameters": null,
    "stageVariables": null,
    "requestContext": {
      "resourceId": "tz879dexv5",
      "resourcePath": "/",
      "httpMethod": "POST",
      "extendedRequestId": "Apsg-GFJIAMF1Og=",
      "requestTime": "09/Jun/2021:09:46:46 +0000",
      "path": "/",
      "accountId": "1234567890",
      "protocol": "HTTP/1.1",
      "stage": "test-invoke-stage",
      "domainPrefix": "testPrefix",
      "requestTimeEpoch": 1623232006020,
      "requestId": "2507c2d5-552a-421e-bc61-e4d740311e9b",
      "identity": {
        "cognitoIdentityPoolId": null,
        "cognitoIdentityId": null,
        "apiKey": "test-invoke-api-key",
        "principalOrgId": null,
        "cognitoAuthenticationType": null,
        "userArn": "arn:aws:iam::1234567890:root",
        "apiKeyId": "test-invoke-api-key-id",
        "userAgent": "aws-internal/3 aws-sdk-java/1.11.1014 Linux/5.4.102-52.177.amzn2int.x86_64 OpenJDK_64-Bit_Server_VM/25.292-b10 java/1.8.0_292 vendor/Oracle_Corporation cfg/retry-mode/legacy",
        "accountId": "1234567890",
        "caller": "1234567890",
        "sourceIp": "test-invoke-source-ip",
        "accessKey": "ABCDEFGHIJKLMNOPQRST",
        "cognitoAuthenticationProvider": null,
        "user": "1234567890"
      },
      "domainName": "testPrefix.testDomainName",
      "apiId": "in3trz7mpg"
    },
    "body": "{\n  \"signature\":\n  {\n    \"timestamp\": \"1529006854\",\n    \"token\": \"a8ce0edb2dd8301dee6c2405235584e45aa91d1e9f979f3de0\",\n    \"signature\": \"50dd7709613e688fd1e2c445b680b1948fe09ea315d472df2c6c8db88154902b\"\n  },\n  \"event-data\":\n  {\n    \"event\": \"opened\",\n    \"timestamp\": 1529006854.329574,\n    \"id\": \"DACSsAdVSeGpLid7TN03WA\"\n  }\n}",
    "isBase64Encoded": false
  }