feature #4 - add function, event adapters and class validator

serverless.yml

@@ -49,6 +49,7 @@ custom:
   funcDir: src/4-framework/functions
   baseApi: sbf/v1
   baseApiInternal: api/v1
+  albHttpListenerArn: ${ssm:/exchangerate/infra/alb/arn}
   serverless-offline:
     port: 4000
     stage: dev

src/4-framework/functions/exchangeRate/_handlers.yml

@@ -5,3 +5,17 @@ updateExchangeRate:
     - sqs:
         arn: ${self:provider.environment.SQS_UPDATE_EXCHANGE_RATE_ARN}
         batchSize: 1
+
+getExchangeRate:
+  handler: ${self:custom.funcDir}/exchangeRate/getExchangeRate.handler
+  events:
+    - alb:
+        listenerArn: ${self:custom.albHttpListenerArn}
+        priority: 1
+        conditions:
+          method: GET
+          path: /${self:custom.baseApi}/exchangerate
+          request:
+            parameters:
+              querystrings:
+                baseCurrency: true

src/4-framework/functions/exchangeRate/getExchangeRate.ts

@@ -0,0 +1,25 @@
+'use strict'
+
+import { ALBEvent } from 'aws-lambda'
+import { GetExchangeRateController } from '../../../3-adapters/controller/exchangeRate/getExchangeRateController'
+import { InputGetExchangeRate } from '../../../3-adapters/serializers/exchangeRate/getExchangeRate/input'
+import { ExchangeRateRepository } from '../../repositories/exchangeRateRepository'
+import { albHttpEventNormalizer } from '../../utility/eventAdapters'
+
+function eventAdapter (event: ALBEvent): InputGetExchangeRate {
+  const body = albHttpEventNormalizer(event)
+  return new InputGetExchangeRate(body)
+
+}
+
+exports.handler = async (event: ALBEvent) => {
+  const getExchangeRateController = new GetExchangeRateController(
+		new ExchangeRateRepository()
+	)
+
+  const input = eventAdapter(event)
+
+  const response = await getExchangeRateController.run(input)
+
+  return response
+}

src/4-framework/repositories/exchangeRateRepository.ts

@@ -1,11 +1,16 @@
 import { ExchangeRate } from '../../1-domain/entities/exchangeRate'
 import { ExchangeRateModel } from '../models/dynamo/exchangeRate'
 import { IExchangeRateRepository } from '../../2-business/repositories/iExchangeRateRepository'
+import { CurrencyEnum } from '../../2-business/enums/currencyEnum'
 
 export class ExchangeRateRepository implements IExchangeRateRepository {
   upsert (entity: ExchangeRate): Promise<ExchangeRate> {
     return ExchangeRateModel.create(entity, {
       overwrite: true
     })
   }
+
+  get (baseCurrency: CurrencyEnum): Promise<ExchangeRate> {
+    return ExchangeRateModel.get({ baseCurrency })
+  }
 }

src/4-framework/utility/classValidator.ts

@@ -0,0 +1,11 @@
+import { validateSync } from 'class-validator'
+
+export class InputClassValidator {
+  errors () {
+    const validationErrors = validateSync(this)
+    return validationErrors.map((e) => ({
+      property: e.property,
+      constraints: e.constraints
+    }))
+  }
+}

src/4-framework/utility/eventAdapters.ts

@@ -0,0 +1,15 @@
+import { ALBEvent } from 'aws-lambda'
+
+export const albHttpEventNormalizer = (event: ALBEvent) => {
+  let payload = {}
+  if (event.queryStringParameters) {
+    payload = { ...event.queryStringParameters }
+  }
+
+  if (event.body) {
+    const body = JSON.parse(event.body)
+    payload = { ...payload, ...body }
+  }
+
+  return payload
+}