# Developing AWS (Advanced)

## Sharding:
Sharding write-heavy partition keys. Distribute work loads evenly across partition keys.

Hotkey - One partition gets too many reads
Hot partiition- one partion receiv higher volume of read-write

## Day 5

Data Velocity & Volume : Kinesis

Example:
Sensor Networks
Click Streams
Log Shipping
Centralizatin

Real-time processing

Kinesis stores data up to 24 hours.
Bottleneck => More shards

Split or Merge Shards as needed.

Producers:
SQS PUT to Kinesis Stream

Consumer

KCL - Kinesis Client Library


Links from Jesse

https://hackmd.io/TnYNDFVTT1Ohfb5qrmAU6g
https://hackmd.io/gv-wMHFgTT63g_sgUK1hfg

**CAP Theorem**

Consistancy Availability Partition Tolerence

SPoF

---
AppSync : fully managed GraphQL

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# Lab 5 Developing microservices on AWS

Build and Run Unit test on the code locally
Generate deployment artifacts and Copy the artifacts to S3 bucket
`aws s3 cp target/tripsearch-1.0.0.jar s3://qls-4160611-bb58f5f7e7f5a9e5-s3bucketlambdacode-y95i7s8z1cl9 --region us-west-2 --profile aws-lab-env`

Create lambda function using the deployment artifact.

aws lambda create-function --function-name microservicesTripSearchFull --runtime java8 --role arn:aws:iam::628405585836:role/microservicesLambdaExecutionRole --handler microservices.lambda.FindAllTripsHandler --code S3Bucket=qls-4160611-bb58f5f7e7f5a9e5-s3bucketlambdacode-y95i7s8z1cl9,S3Key=tripsearch-1.0.0.jar --timeout 15 --description "CloudAir TripSearch microservice - FindAllTrips" --memory-size 1024 --profile aws-lab-env

An output similar to the following will be visible:

{
    "LastUpdateStatus": "Successful",
    "FunctionName": "microservicesTripSearchFull",
    "LastModified": "2021-04-24T16:52:37.328+0000",
    "RevisionId": "95f61dda-0a15-4442-8cc5-a57e625a057b",
    "MemorySize": 1024,
    "State": "Active",
    "Version": "$LATEST",
    "Role": "arn:aws:iam::628405585836:role/microservicesLambdaExecutionRole",
    "Timeout": 15,
    "Handler": "microservices.lambda.FindAllTripsHandler",
    "Runtime": "java8",
    "TracingConfig": {
        "Mode": "PassThrough"
    },
    "CodeSha256": "YPUxKNfDAZRxNb8pj9L9YOJuGKKZrB/AwmWKTXLm8uc=",
    "Description": "CloudAir TripSearch microservice - FindAllTrips",
    "CodeSize": 9737281,
    "FunctionArn": "arn:aws:lambda:us-west-2:628405585836:function:microservicesTripSearchFull",
    "PackageType": "Zip"
}

if the deployment artifact contains multiple handlers, a separate lambda funtion can be created for each handler. (Just chnage the handler name in the command as shown below ):

aws lambda create-function --function-name microservicesTripSearchFromCity --runtime java8 --role arn:aws:iam::628405585836:role/microservicesLambdaExecutionRole --handler microservices.lambda.FindTripsFromCityHandler --code S3Bucket=qls-4160611-bb58f5f7e7f5a9e5-s3bucketlambdacode-y95i7s8z1cl9,S3Key=tripsearch-1.0.0.jar --timeout 15 --description "CloudAir TripSearch microservice - FindTripsFromCity" --memory-size 1024 --profile aws-lab-env


aws lambda create-function --function-name microservicesTripSearchToCity --runtime java8 --role arn:aws:iam::628405585836:role/microservicesLambdaExecutionRole  --handler microservices.lambda.FindTripsToCityHandler --code S3Bucket=qls-4160611-bb58f5f7e7f5a9e5-s3bucketlambdacode-y95i7s8z1cl9,S3Key=tripsearch-1.0.0.jar --timeout 15 --description "CloudAir TripSearch microservice - FindTripsToCity" --memory-size 1024 --profile aws-lab-env

Go to Api Gateway and create a new REST api
Enter API name, path and enable CORS

Create Resource --> Resource wil be created

from actions, choose create method, select GET and continue
Integrate with the Lambda function

Click Save and Test. We will see something like this;

In the integration request, create mapping template and add mapping template. Test the API

aws cloudformation package --template template.yml --s3-bucket qls-4160611-bb58f5f7e7f5a9e5-s3bucketlambdacode-y95i7s8z1cl9 --output-template template-export.yml --profile aws-lab-env

http://qls-4160611-bb58f5f7e7f5a9e5-s3bucketwebsite-hz2ayjsge4m.s3-website-us-west-2.amazonaws.com
aws s3 sync . s3://qls-4160611-bb58f5f7e7f5a9e5-s3bucketwebsite-hz2ayjsge4m --profile aws-lab-env