API Gateway+LambdaでJSONを受け取る

API GatewayでHTTP APIを使ってみた

API Gateway（HTTP API）は低レイテンシー、低コストということで使ってみた。
Lambda（Python）でJSONデータを受け取る場合に REST API と HTTP API で取り出し方が違うのでメモする。

#JSONデータ
{
    "operation": "PUT",
    "data": {
        "temp":"28.0",
        "humid":"41.2"
    }
}

HTTP APIの場合

$ curl -v -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"operation": "PUT", "data": {"temp":"28.0","humid":"41.2"}}' https://{API ID}.execute-api.{リージョン}.amazonaws.com/{リソースパス}

# Lambda関数（Python)
import json

def lambda_handler(event, context):
  operation = json.loads(event.get('body', '{}')).get('operation')
  data = json.loads(event.get('body', '{}')).get('data')
  temp = data['temp']
  humid = data['humid']

  print("operation: " + operation)
  print("temp: " + temp)
  print("humid: " + humid)

  return {
    'statusCode': 200,
    'body': json.dumps('OK.')
  }

# lambda_handler 引数eventの中身
event: 
{
    "version": "2.0",
    "routeKey": "POST {リソースパス}",
    "rawPath": "{リソースパス}",
    "rawQueryString": "",
    "headers": {
       省略
       :
    },
    "requestContext": {
       省略
       :
    },
    "body": "{\"operation\":\"PUT\",\"data\":{\"temp\":\"28.0\",\"humid\":\"41.2\"}}",
    "isBase64Encoded": false
}

REST APIの場合

$ curl -v -H "Accept: application/json" -H "Content-type: application/json" -X POST -d '{"operation": "PUT", "data": {"temp":"28.0","humid":"41.2"}}' https://{API ID}.execute-api.{リージョン}.amazonaws.com/{API デプロイのステージ名}

# Lambda関数(Python)
import json

def lambda_handler(event, context):
  operation = event['operation']
  data = event['data']
  temp = data['temp']
  humid = data['humid']

  print("operation: " + operation)
  print("temp: " + temp)
  print("humid: " + humid)

  return {
    'statusCode': 200,
    'body': json.dumps('OK.')
  }

# lambda_handler 引数eventの中身
event: {"operation": "PUT", "data": {"temp": "28.0", "humid": "41.2"}}