AWS & Serverless Flashcards
AWS API Gateway allows you to create, publish, maintain, monitor and secure what?
APIs
Can the APIs you create be scalable by default?
Yes
APIs created can access what two key things?
AWS Web services & Data stored on AWS Cloud
A client hits an registered API endpoint that’s connected to what?
API Gateway
Once the client hits an endpoint the API Gateway receives a method request that is processed through Gateway’s integration. It can respond by calling a Lambda or accessing data through services such as -> DynamoDB, EC2, S3 etc. This process is considered what?
An integrational request.
The AWS API Gateway is considered to be a ____ between your app and AWS services
mediator
An incoming response from the executed service (Lambda or another service) is processed through the Gateway’s integration than returns to the client as a method response. What is this process called?
An integrational response.
You just created a new API what is the next step?
Create a resource
What is a resource?
The path that is the direct endpoint the client can hit in order to trigger an action
Your new API now has a resource what is the next step in order to gain use out of the resourcePath (endpoint)
Add an access method for that resourcePath (REST API HTTP methods… GET, POST etc)
The resource of the new API is set up with an access method, what is the next thing that must be done?
You must stage (or deploy) your API.
When defining an access method for a resource you must specify what?
An integration type -> Lambda Function, HTTP, Mock or other Service.
AWS CloudWatch essentially allows you to do what?
Watch/Monitor -> AWS Cloud resources/services
AWS CloudWatch has logging, and metrics but what another key thing can it do?
send out alerts or alarms about errors or any information.
You create what based on CloudWatch monitoring feedback?
events to be triggered.
These trigger events include:
A Lambda or other cloud services and starting/shutting down instances.
AWS offers an event-driven computing cloud service, that utilizes FaaS on a pay-per-use basis. What is the name of the core service that makes all this work?
AWS Lambda
The benefit of AWS Lambda from a developer sense is that….
You only worry about the code (serveless, amazon takes care of server scaling and systems)
Each Lambda function runs based off of some cloud service or http event. Lambda’s architecture is made up of what 3 three things?
Stateless function, Isolated in its own environment, is its own resource in the AWS system.
The Lambda function is stateless/immutable, it will listen to an “ALLOWED” event/trigger from a resource and make changes/updates to “ALLOWED” resources. When these changes are made what happens next?
The lambda returns an integrational response to AWS API Gateway -> that then returns a payload response to the client.
What is the benefit of AWS Lambda (FaaS) from a business sense.
Big savings ($$). The cost to time ratio of getting the architecture setup is tremendously low in cost and quick in time.
Step Functions are basically what
State Machines
State Machines (step functions) allow you to organize ____ and build a back in architecture that perform different things.
Lambdas
In a state machine architecture it is composed of lambdas but how when lambdas are stateless?
One lambda functions output (data/state) can be used as input in the NEXT lambda function. Hints “Step Functions” they run step by step.
Where do you go in AWS to create state machines?
AWS Step Function service console
A State Machine is made up of a few key parts, but the meat of the state machine can be found in what property of the state machine JSON.
“State”
The states key in the State Machine defines what?
Different states (step functions) that compose to make the state machine.
Each “state” in the state machine has a name, type, resource, resultPath & end. What is the name referring to?
The name of the step function
Each “state” in the state machine has a name, type, resource, resultPath & end. What is the type defining?
What action the state or step function will take/execute. As well as what type of state it is.
Each “state” in the state machine has a name, type, resource, resultPath & end. What is the Resource key referring to?
What Lambda will be called. Typically this key will have a Lambda arn:id to identify the lambda needed.
Each “state” in the state machine has a name, type, resource, resultPath & end. What is the resultPath referring to?
Where you can find in the state’s or step function’s output (object) the data or state changes.
The are multiple ways to get a state machine to began. How can you use a lambda to do this?
A Lambda will listen for an event in order to trigger the 1st step function to execute in the chain.
How does the lambda know what state machine to execute and what is the lambda acting as?
The lambda acts as an execution machine, which will execute the right state machine based on arn:id
What is serverless?
A way to cloud compute client resource changes and application responses without worrying about the server. (Services used will handle provisioning, scaling and allocation of servers)
How does serverless run at large scale?
It uses multiple stateless computation containers (functions) That are event-triggered. The cloud provider manages this.
A middle man must be setup between the client & cloud provider in order to make this all work. What is that middle man?
An API Gateway
FaaS is basically the system architecture used in serverless. What does FaaS stand for.
Functions As A System
Serveless architecture is composed of what 5 things?
Web server, Lamda Functions (FaaS), security token service, user authentication, and database.
