Simplified constructors and xray configuration

src/config/DependencyInjection.ts

@@ -0,0 +1,21 @@
+import { LambdaClient } from '@aws-sdk/client-lambda';
+import { S3Client } from '@aws-sdk/client-s3';
+import * as AWSXRay from 'aws-xray-sdk';
+import { Container, Service } from 'typedi';
+import { IInvokeConfig } from '../models';
+import { Configuration } from '../utils/Configuration';
+
+@Service()
+export class DependencyInjection {
+	public static register() {
+		const config: IInvokeConfig = Configuration.getInstance().getInvokeConfig();
+
+		Container.set(LambdaClient, AWSXRay.captureAWSv3Client(new LambdaClient(config.params)));
+		Container.set(S3Client, AWSXRay.captureAWSv3Client(new S3Client(config)));
+
+		const isOffline = (process.env.IS_OFFLINE ?? false) as boolean;
+		if (isOffline) {
+			// Needed for later.
+		}
+	}
+}

src/handler.ts

@@ -1,15 +1,6 @@
+import { DependencyInjection } from './config/DependencyInjection';
 import { certGen } from './functions/certGen';
 
-const isOffline: boolean = !process.env.BRANCH || process.env.BRANCH === 'local';
+DependencyInjection.register();
 
-let credentials = {};
-
-if (isOffline) {
-	credentials = {
-		accessKeyId: 'accessKey1',
-		secretAccessKey: 'verySecretKey1',
-	};
-}
-
-export { credentials };
 export { certGen as handler };

src/services/CertificateGenerationService.ts

@@ -4,7 +4,7 @@ import { GetObjectOutput } from '@aws-sdk/client-s3';
 import { getProfile } from '@dvsa/cvs-feature-flags/profiles/vtx';
 import { toUint8Array } from '@smithy/util-utf8';
 import moment from 'moment';
-import { Inject, Service } from 'typedi';
+import { Service } from 'typedi';
 import {
 	ICertificatePayload,
 	ICustomDefect,
@@ -51,15 +51,12 @@ import { S3BucketService } from './S3BucketService';
  */
 @Service()
 class CertificateGenerationService {
-	private readonly s3Client: S3BucketService;
-	private readonly config: Configuration;
-	private readonly lambdaClient: LambdaService;
-
-	constructor(@Inject() s3Client: S3BucketService, @Inject() lambdaClient: LambdaService) {
-		this.s3Client = s3Client;
-		this.config = Configuration.getInstance();
-		this.lambdaClient = lambdaClient;
-	}
+	private readonly config: Configuration = Configuration.getInstance();
+
+	constructor(
+		private s3Client: S3BucketService,
+		private lambdaClient: LambdaService
+	) {}
 
 	/**
 	 * Generates MOT certificate for a given test result

src/services/CertificateUploadService.ts

@@ -1,5 +1,5 @@
 import { PutObjectCommandOutput } from '@aws-sdk/client-s3';
-import { Inject, Service } from 'typedi';
+import { Service } from 'typedi';
 import { IGeneratedCertificateResponse } from '../models';
 import { S3BucketService } from './S3BucketService';
 
@@ -8,11 +8,7 @@ import { S3BucketService } from './S3BucketService';
  */
 @Service()
 class CertificateUploadService {
-	private readonly s3BucketService: S3BucketService;
-
-	constructor(@Inject() s3BucketService: S3BucketService) {
-		this.s3BucketService = s3BucketService;
-	}
+	constructor(private s3BucketService: S3BucketService) {}
 
 	/**
 	 * Uploads a generated certificate to S3 bucket

src/services/LambdaService.ts

@@ -1,23 +1,14 @@
 import { InvocationRequest, InvocationResponse, InvokeCommand, LambdaClient } from '@aws-sdk/client-lambda';
-import { Inject, Service } from 'typedi';
-import { IInvokeConfig } from '../models';
+import { Service } from 'typedi';
 import { ERRORS } from '../models/Enums';
 import { HTTPError } from '../models/HTTPError';
-import { Configuration } from '../utils/Configuration';
-
-import AWSXRay from 'aws-xray-sdk';
 
 /**
  * Service class for invoking external lambda functions
  */
 @Service()
 class LambdaService {
-	public readonly lambdaClient: LambdaClient;
-
-	constructor(@Inject() lambdaClient: LambdaClient) {
-		const config: IInvokeConfig = Configuration.getInstance().getInvokeConfig();
-		this.lambdaClient = AWSXRay.captureAWSv3Client(new LambdaClient({ ...lambdaClient, ...config.params }));
-	}
+	constructor(private lambdaClient: LambdaClient) {}
 
 	/**
 	 * Invokes a lambda function based on the given parameters

src/services/S3BucketService.ts

@@ -8,22 +8,14 @@ import {
 	PutObjectCommandOutput,
 	S3Client,
 } from '@aws-sdk/client-s3';
-import AWSXRay from 'aws-xray-sdk';
-import { Inject, Service } from 'typedi';
-import { IS3Config } from '../models';
-import { Configuration } from '../utils/Configuration';
+import { Service } from 'typedi';
 
 /**
  * Service class for communicating with Simple Storage Service
  */
 @Service()
 class S3BucketService {
-	public readonly s3Client: S3Client;
-
-	constructor(@Inject() s3Client: S3Client) {
-		const config: IS3Config = Configuration.getInstance().getS3Config();
-		this.s3Client = AWSXRay.captureAWSv3Client(new S3Client({ ...s3Client, ...config }));
-	}
+	constructor(private s3Client: S3Client) {}
 
 	/**
 	 * Uploads a file to an S3 bucket