pspring-aws

This framework is member of pspring based family of frameworks. It provides a means to access aws resources with minimal code. boto3 library is used internally for http requests.

All the default variables are listed in defaultvars.py

Annotations / Decorators that come along with this framework are listed below

• @SecretValue(name="",region="",column="",columns=[])

  This is a class decorator can be used to retrieve value of secret in AWS secrets manager. We could also specify a list of columns or a single column name from the secret response to be retrived. A method named "getSecretValue" will be available on the class.

• @DynamoDBTable(tableName="",primaryKey="",sortKey="",ttlColumnName="",ttl="")

  This is a class decorator which can be tagged with a dynamodb table. Once tagged with this decorator, the class will have implementations of get and put methods. get(self,primaryKey,sortKey="",columns="",column="") method can be used to retrive only specific columns put(self,data) can be used to insert data

• @LambdaHandler(type="lambdaproxy")

  This is a class decorator which provides below functionalities. You should implement "handler" method which will be enhanced

  1. debug,info,warn,error - This will log a message will required tracking fields like requestId etc.
  2. handle cold start requests with requestId = "COLD_START_WARMER"
  3. addToLogger method can be used to add a field to all logging messages.
  4. returns a 200 response along with the dictionary returned from the "handler" method as json.
  5. handles all exceptions and returns gracefully a 500 Internal server error.

Below exceptions are available from this framework

• LambdaException
• NotFoundException
• UnAuthorizedException
• InternalServerException
• CreatedException
• RedirectException

• RealTimeSecretsMgrConfigProvider

  This along with https://github.com/vasudevan-palani/appsync-client.git works as a real time secrets manager ( what this means is, you will get notified about the changes to secrets mngr's value as a push event )

    from pspring import Configuration
  
    config = Configuration.getConfig(__name__)
  
    Configuration.initializer([
      RealTimeSecretsMgrConfigProvider(secretId="mysecretId",region="us-east-1")
    ])
  

• SecretsMgrConfigProvider

  ConfigurationProvider for secrets manager in aws to work alongside pspring.Configuration

      from pspring import Configuration
  
      config = Configuration.getConfig(__name__)
  
      Configuration.initializer([
        SecretsMgrConfigProvider(secretId="mysecretId",region="us-east-1")
      ])
  

• SecretsManager

  Utility class to interact with aws secrets manager encapsulating the boiler plate code

    from pspringaws import SecretsManager
  
    secretsmngr = SecretsManager(secretId="mysecretId")
  
    secretsmngr.getSecretValue()
  

• DynamoDBTable

  Utility class to interact with aws dynamodb encapsulating the boiler plate code

    from pspringaws import DynamoDBTable
  
    secretsmngr = DynamoDBTable(tableName="mytable",primaryKey="primaryKey",sortKey="sortKey")
  
    item = secretsmngr.get("primaryKeyValue")
  
    item = secretsmngr.put(primaryKeyValue,item)
  

Example:

from pspring import *
from pspringaws import *


@LambdaHandler()
class MyHandler():
    @Autowired()
    def __init__(self,customerbackend:CustomerBackend, cache:DataCache):
        self.customerbackend = customerbackend
        self.cache = cache

    def handler(self,event,context):
      return self.customerbackend(...)

context.initialize()
newhandler = MyHandler()
def handler(event,context):
    return newhandler.handler(event,context)

To do:

• Support Lambda integration types