distributedlife / conventionaljs

Conventional tests for your JS and TS

conventionaljs

Conventional tests for your JS and TS.

There is only one rule so far and it's incomplete.

• Make sure AWS Lambda event handler input parameters don't escape the file they are defined in.

AWS Lambda Handler Matchers

The following is considered an AWS Lambda handlers if all are true:

• Must be an export of a root source file (file not imported by another source file)
• Looks like one of the following:
  • has JSDoc annotation matching an AWS event type e.g. AWSLambda.DynamoDBStreamEvent for the first param
  • has three params (event, context, callback) in that order and with that name
  • has two params (event, context) is async
  • has one param (event) is async and the function name is called "handler"

The following are considered AWS Lambda Event Types

• AWSLambda.ALBEvent
• AWSLambda.APIGatewayEvent
• AWSLambda.CloudFrontEvent
• AWSLambda.CloudWatchLogsEvent
• AWSLambda.CognitoUserPoolEvent
• AWSLambda.DynamoDBStreamEvent
• AWSLambda.KinesisStreamEvent
• AWSLambda.S3CreateEvent
• AWSLambda.S3Event
• AWSLambda.SNSEvent
• AWSLambda.SQSEvent

Usage

You'll need entente or ts-morph for this.

entente (known entrypoints only at the moment)

const { createProject } = require("entente");
createProject('./src/index.js');

checkProject(project) 

ts-morph (find entrypoints in a source tree)

const compilerOptions = {
  allowJs: true,
  checkJs: true,
  noEmit: true,
  resolveJsonModule: true,
};

const project = new Project({ compilerOptions });
project.resolveSourceFileDependencies();
project.addSourceFilesAtPaths(['./src/**/*.js', "!./src/**/*.spec.js"]);

checkProject(project) 

Todos

• Make it work with commonjs modules. ts-morph is having a hard time here.
• Make sure it doesn't escape through a renamed reference.

Ideas to explore

• express request/response objects are not passed around
• GraphQL response objects are converted to view models before use
• types defined externally to the project can only be passed out of the file where they are first used (don't couple yourself to external objects) -- but you can define them anywhere
• types defined externally to the project can only be used in leaf (files that do not reference other source files) or entrypoint files (files not referened by other source files)