About

Serverless function created with npm serverless. GET request to https://u1l461m5nl.execute-api.us-east-1.amazonaws.com/dev/hello-world will return a json blob that is the full event (the 'out-of-the-box' hello-world function):

{"message"{
  "message": "Go Serverless v1.0! Your function executed successfully!",
  "input": {
    "resource": "/hello-world",
    "path": "/hello-world",
    "httpMethod": "GET",
    "headers": {
      "Accept": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
      "Accept-Encoding": "gzip, deflate, br",
      "Accept-Language": "en-US,en;q=0.5",
      "CloudFront-Forwarded-Proto": "https",
      "CloudFront-Is-Desktop-Viewer": "true",
      "CloudFront-Is-Mobile-Viewer": "false",
      "CloudFront-Is-SmartTV-Viewer": "false",
      "CloudFront-Is-Tablet-Viewer": "false",
      "CloudFront-Viewer-Country": "US",
      "Host": "u1l461m5nl.execute-api.us-east-1.amazonaws.com",
      "upgrade-insecure-requests": "1",
      "User-Agent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:61.0) Gecko/20100101 Firefox/61.0",
      "Via": "2.0 ad71fd218ad805257f43d37e2ed4879f.cloudfront.net (CloudFront)",
      "X-Amz-Cf-Id": "-z7z3OFSfoU2i0qtYume4gZF-zbM-pQIXzPhXFtyGOAx0SGbflw5hA==",
      "X-Amzn-Trace-Id": "Root=1-5b76f76b-0afe25381dde3e0003bcc1ba",
      "X-Forwarded-For": "98.161.244.202, 52.46.35.71",
      "X-Forwarded-Port": "443",
      "X-Forwarded-Proto": "https"
    },
    "queryStringParameters": null,
    "pathParameters": null,
    "stageVariables": null,
    "requestContext": {
      "resourceId": "wwkzhe",
      "resourcePath": "/hello-world",
      "httpMethod": "GET",
      "extendedRequestId": "LxuYwGbIoAMFX7w=",
      "requestTime": "17/Aug/2018:16:27:23 +0000",
      "path": "/dev/hello-world",
      "accountId": "441850989636",
      "protocol": "HTTP/1.1",
      "stage": "dev",
      "requestTimeEpoch": 1534523243217,
      "requestId": "6b9ec50e-a23a-11e8-93a1-511793cf37cd",
      "identity": {
        "cognitoIdentityPoolId": null,
        "accountId": null,
        "cognitoIdentityId": null,
        "caller": null,
        "sourceIp": "98.161.244.202",
        "accessKey": null,
        "cognitoAuthenticationType": null,
        "cognitoAuthenticationProvider": null,
        "userArn": null,
        "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:61.0) Gecko/20100101 Firefox/61.0",
        "user": null
      },
      "apiId": "u1l461m5nl"
    },
    "body": null,
    "isBase64Encoded": false
  }
}

Add new function

If the current handler.js file is small, add new functions directly into the handler file. Use the same config for each, starting with module.exports.<functionName> = (event, context, callback) {...} Note: if you use an external package, remember to install it with npm. The serverless quick-start docs do not mention that.

Provisioning infrastructure (e.g. a database)

One can provision a DynamoDB table (noSQL) using CloudFormation Add configuration to the serverless.yml file, using the CloudFormation syntax

Deploy

run sls deploy to deploy the functions.

Metrics

The sls metrics command will return service level information about the number of times the functions have been called and some other metrics. For example:

Service wide metrics
August 17, 2018 11:22 AM - August 18, 2018 11:22 AM

Invocations: 4
Throttles: 0
Errors: 2
Duration (avg.): 73.59ms

To get function level metrics, add the -f flag, followed by the function name. For example: sls metrics -f saveName returns:

saveName
August 17, 2018 11:27 AM - August 18, 2018 11:27 AM

Invocations: 3
Throttles: 0
Errors: 2
Duration (avg.): 40.45ms

(the erros above were caused by forgetting to install the aws-sdk).

The command sls logs -f <function Name> will provide function logs. For example: sls logs -f saveName returns:

START RequestId: 3368b1ed-a315-11e8-b5ab-f564e5b6dd7e Version: $LATEST
2018-08-18 11:33:29.381 (-07:00)  3368b1ed-a315-11e8-b5ab-f564e5b6dd7e  HELLO! Request to save name Alex with age 24
END RequestId: 3368b1ed-a315-11e8-b5ab-f564e5b6dd7e
REPORT RequestId: 3368b1ed-a315-11e8-b5ab-f564e5b6dd7e  Duration: 110.02 ms Billed Duration: 200 ms   Memory Size: 1024 MB  Max Memory Used: 34 MB

Current Functions

Service Information service: hello-world stage: dev region: us-east-1 stack: hello-world-dev api keys: None endpoints: GET - https://u1l461m5nl.execute-api.us-east-1.amazonaws.com/dev/hello-world GET - https://u1l461m5nl.execute-api.us-east-1.amazonaws.com/dev/hello-name functions: helloWorld: hello-world-dev-helloWorld helloName: hello-world-dev-helloName

Removing a service (to prevent incurring charges)

Issue the comman sls remove