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This commit is contained in:
Dheeraj Mummareddy
2018-03-13 12:03:23 -04:00
parent 05a9c030c0
commit 3f9a5a254e
6 changed files with 33 additions and 18 deletions
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serverless/README.md
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@ -18,21 +18,33 @@ Following are optimization katas you should be aware of while building a serverl
applications
* The Lean function
* Concise logic
* Efficient/single purpose code
* ephemeral environment
* Concise logic - Use functions to transform, not transport (utilize some of the
integration available from the provider to transport), and make sure you read only
what you need
* Efficient/single purpose code - avoid conditional/routing logic and break down
into individual functions, avoid "fat"/monolithic functions and control the
dependencies in the function deployment package to reduce the load time for your
function
* ephemeral environment - Utilize container start for expensive initializations
* Eventful Invocations
* Succinct payloads
* resilient routing
* concurrent execution
* Succinct payloads - Scrutinize the event as much as possible, and watch for
payload constraints (async - 128K)
* resilient routing - Understand retry policies and leverage dead letter queues
(SQS or SNS for replays) and remember retries count as invocations
* concurrent execution - lambda thinks of it's scale in terms of concurrency and
its not request based/duration based. Lambda will spin up the number of instances
based on the request.
* Coordinated calls
* Decoupled via APIs
* scale-matched downstream
* secured
* Decoupled via APIs - best practice to setup your application is to have API's as
contracts that ensures separation of concerns
* scale-matched downstream - make sure when Lambda is calling downstream
components, you are matching scale configuration to it (by specifying max
concurrency based on downstream services)
* secured - Always ask a question, do I need a VPC?
* Serviceful operations
* Automated operations
* monitored applications
* Innovation mindset
* Automated - use automated tools to manage and maintain the stack
* monitored applications - use monitoring services to get holistic view of your
serverless applications
## Intent
@ -84,7 +96,8 @@ database service also provided by Amazon.
## AWS lambda function implementation
AWS lambda SDK provides pre-defined interface `com.amazonaws.services.lambda.runtime
[https://aws.amazon.com/sdk-for-java/](AWS Lambda SDK) provides pre-defined interface
`com.amazonaws.services.lambda.runtime
.RequestHandler` to implement our lambda function.
```java
@ -123,9 +136,9 @@ dependencies of the function.
Based on the configuration in `serverless.yml` serverless framework creates following
resources
* cloud formation stack for S3 (ServerlessDeploymentBucket)
* CloudFormation stack for S3 (ServerlessDeploymentBucket)
* IAM Role (IamRoleLambdaExecution)
* cloud watch (log groups)
* CloudWatch (log groups)
* API Gateway (ApiGatewayRestApi)
* Lambda function
* DynamoDB collection