aws-chicago-meetup-226541826

Code for a talk on Lambda & API Gateway at the Dec 2, 2015 AWS Chicago Meetup

Manual Build in the AWS Console

Create the dynamodb table

1. Create a table named cats with a string hash key name
2. Accept all other defaults and create the table

Create the lambda function

1. Create a new function using the simple-mobile-backend template
2. Create the suggested Basic with DynamoDB role if it doesn't already exist
3. Name it cats

Note that this lambda function multiplexes operations based on the body. It doesn't have to work that way.

Test out some lambda invocations:

Create a cat:

{
  "operation": "create",
  "TableName": "cats",
  "Item": {
      "name": "henry",
      "status": "hungry"
  }
}

Get a cat:

{
  "operation": "read",
  "TableName": "cats",
  "Key": {
      "name": "henry"
  }
}

List all cats:

{
  "operation": "read",
  "TableName": "cats",
  "Key": {
      "name": "henry"
  }
}

Update a cat:

{
  "operation": "create",
  "TableName": "cats",
  "Item": {
      "name": "henry",
      "status": "sleepy"
  }
}

Create a new API Gateway API

1. Name it MeetupCats
2. Create a new /cats resource
3. Create a new /{name} resource under /cats
4. Create the following methods with the corresponding mapping templates:

POST /cats

{
  "operation": "create",
  "TableName": "cats",
  "Item": $input.json('$')
}

GET /cats

{
    "operation": "list",
    "TableName": "cats"
}

GET /cats/{name}

{
    "operation": "read",
    "TableName": "cats",
    "Key": {
        "name": "$input.params('name')"
    }
}

PUT /cats/{name}

{
    "operation": "create",
    "TableName": "cats",
    "Item": {
        "name": "$input.params('name')",
        "status": "$input.path('$.status')"
    }
}