Introduction

Proof of concept for app using FaaS approach.

Current state

• App running using a mLab database with ~500.000 records linked with boxes ids.

To be

• New re-boxing process that will merge two boxes into one.
• Reboxing will create a new box id but with a track of the boxes merged.
• It should be able to perform a query with the new box id and get the records related.

App Model

for a process from a system that has a set of records linked to a main object called "boxes". After the migration the documents will be contained in a new box id. Information about the link of the new box id and the documents is needed.

Environment variables

Environment variables for functions must be defined in the template.yaml file. You can define default values and create an alternative file (env.json) for a local debug.

Environment json format file

{
  "Function": 
  { 
    "EnvVar": "EnvValue"
  } 
}

Local debugging

The following commands allow you to perform a local debug using vscode , sam-cli and docker

• Build the function using the docker lambda python containers.

sam build --use-container

• Start local api after a build using the environment file env.json

sam local start-api --env-vars env.json
# This command will use the .aws-sam/build directory, even you can change the files without reloading the api.

Deployment Information

Once the build is performed it is located in .aws-sam/build directory with a subfolder per each function. In case that the function has 3rd party libraries it is necessary to create a package from this folder to deploy it.

sam build --use-container
cd .aws-sam/build
sam package --template-file template.yaml --s3-bucket YOUR_S3_BUCKET --output-template-file packaged.yaml
sam deploy --region YOUR_REGION --template-file packaged.yaml --stack-name YOUR_STACK_NAME --capabilities CAPABILITY_IAM