Refactor client classes to make their properties private and readonly

where relevant.

src/internal/client.ts

@@ -10,8 +10,8 @@ import { HTTPHeaders } from './http'
  * usage examples.
  */
 export class AWSClient {
-    awsConfig: AWSConfig
-    serviceName: string
+    readonly awsConfig: AWSConfig
+    readonly serviceName: string
 
     private _endpoint?: Endpoint
 
@@ -66,6 +66,6 @@ export class AWSClient {
  * Type alias representing the result of an AWSClient.buildRequest call
  */
 export interface AWSRequest {
-    url: string
-    headers: HTTPHeaders
+    readonly url: string
+    readonly headers: HTTPHeaders
 }

src/internal/event-bridge.ts

@@ -12,11 +12,9 @@ import { HTTPHeaders, HTTPMethod } from './http'
  * Class allowing to interact with Amazon AWS's Event Bridge service
  */
 export class EventBridgeClient extends AWSClient {
-    method: HTTPMethod
-
-    commonHeaders: HTTPHeaders
-
-    signature: SignatureV4
+    private readonly signature: SignatureV4
+    private readonly method: HTTPMethod
+    private readonly commonHeaders: HTTPHeaders
 
     constructor(awsConfig: AWSConfig) {
         super(awsConfig, 'events')
@@ -41,8 +39,8 @@ export class EventBridgeClient extends AWSClient {
 
     /**
      * Sends custom events to Amazon EventBridge so that they can be matched to rules.
-     *  
-     * @param {PutEventsInput} input - The input for the PutEvents operation. 
+     *
+     * @param {PutEventsInput} input - The input for the PutEvents operation.
      * @throws {EventBridgeServiceError}
      * @throws {InvalidSignatureError}
      */

src/internal/kinesis.ts

@@ -18,20 +18,9 @@ https://docs.aws.amazon.com/kinesis/latest/APIReference/API_Operations.html
  * Allows interacting with the Kinesis API.
  */
 export class KinesisClient extends AWSClient {
-    /**
-     * The SignatureV4 object used to sign requests.
-     */
-    signature: SignatureV4
-
-    /**
-     * The common headers that are used for all requests.
-     */
-    commonHeaders: HTTPHeaders
-
-    /**
-     * The version of the Kinesis API that is used for all requests.
-     */
-    serviceVersion: string
+    private readonly signature: SignatureV4
+    private readonly commonHeaders: HTTPHeaders
+    private readonly serviceVersion: string
 
     /**
      * A constructor function that creates a new instance of the Kinesis class.
@@ -583,8 +572,8 @@ export class GetRecordsResponse {
      * The number of milliseconds the GetRecords response is from the
      * tip of the stream, indicating how far behind current time the
      * consumer is.
-     * 
-     * A value of zero indicates that record processing is caught 
+     *
+     * A value of zero indicates that record processing is caught
      * up, and there are no new records to process at this moment.
      */
     millisBehindLatest: number

src/internal/kms.ts

@@ -12,10 +12,9 @@ import { InvalidSignatureError, SignatureV4 } from './signature'
  * Class allowing to interact with Amazon AWS's KMS service
  */
 export class KMSClient extends AWSClient {
-    method: HTTPMethod
-    commonHeaders: HTTPHeaders
-
-    signature: SignatureV4
+    private readonly signature: SignatureV4
+    private readonly method: HTTPMethod
+    private readonly commonHeaders: HTTPHeaders
 
     /**
      * Create a KMSClient

src/internal/s3.ts

@@ -10,7 +10,7 @@ import { InvalidSignatureError, SignatureV4 } from './signature'
 
 /** Class allowing to interact with Amazon AWS's S3 service */
 export class S3Client extends AWSClient {
-    signature: SignatureV4
+    private readonly signature: SignatureV4
 
     /**
      * Create a S3Client
@@ -222,7 +222,9 @@ export class S3Client extends AWSClient {
                 path: `/${bucketName}/${objectKey}`,
                 headers: {
                     Host: this.endpoint.host,
-                    ...(params?.contentDisposition && { 'Content-Disposition': params.contentDisposition }),
+                    ...(params?.contentDisposition && {
+                        'Content-Disposition': params.contentDisposition,
+                    }),
                     ...(params?.contentEncoding && { 'Content-Encoding': params.contentEncoding }),
                     ...(params?.contentLength && { 'Content-Length': params.contentLength }),
                     ...(params?.contentMD5 && { 'Content-MD5': params.contentMD5 }),
@@ -654,7 +656,7 @@ type StorageClass =
 export interface PutObjectParams {
     /**
      * Specifies presentational information for the object.
-     * 
+     *
      * For more information, see https://www.rfc-editor.org/rfc/rfc6266#section-4.
      */
     contentDisposition?: string
@@ -663,15 +665,15 @@ export interface PutObjectParams {
      * Specifies what content encodings have been applied to the object and thus
      * what decoding mechanisms must be applied to obtain the media-type referenced
      * by the ContentType option.
-     * 
+     *
      * For more information, see https://www.rfc-editor.org/rfc/rfc9110.html#field.content-encoding.
      */
     contentEncoding?: string
 
     /**
      * Size of the body in bytes. This parameter is useful when the size of the body cannot be
      * determined automatically.
-     * 
+     *
      * For more information, see https://www.rfc-editor.org/rfc/rfc9110.html#name-content-length.
      */
     contentLength?: string
@@ -680,15 +682,15 @@ export interface PutObjectParams {
      * The base64-encoded 128-bit MD5 digest of the message (without the headers) according to RFC 1864.
      * This header can be used as a message integrity check to verify that the data is the same data that
      * was originally sent.
-     * 
+     *
      * Although it is optional, we recommend using the Content-MD5 mechanism as an end-to-end integrity
      * check.
      */
     contentMD5?: string
 
     /**
      * A standard MIME type describing the format of the contents.
-     * 
+     *
      * For more information, see https://www.rfc-editor.org/rfc/rfc9110.html#name-content-type.
      */
     contentType?: string

src/internal/secrets-manager.ts

@@ -13,17 +13,9 @@ import { InvalidSignatureError, SignatureV4 } from './signature'
  * Class allowing to interact with Amazon AWS's SecretsManager service
  */
 export class SecretsManagerClient extends AWSClient {
-    /**
-     * HTTP Method to use when interacting with the Secrets Manager service.
-     */
-    method: HTTPMethod
-
-    /**
-     * HTTP headers to use accross all requests to the Secrets Manager service.
-     */
-    commonHeaders: HTTPHeaders
-
-    signature: SignatureV4
+    private readonly signature: SignatureV4
+    private readonly method: HTTPMethod
+    private readonly commonHeaders: HTTPHeaders
 
     /**
      * Create a SecretsManagerClient

src/internal/sqs.ts

@@ -71,19 +71,24 @@ export class SQSClient extends AWSClient {
              * See https://docs.aws.amazon.com/AWSSimpleQueueService/latest/APIReference/API_SendMessage.html#SQS-SendMessage-request-MessageAttributes
              * for more information.
              */
-            const attributeParameters = Object.entries(options.messageAttributes).reduce((params, [name, attribute], i) => {
-                const valueParameterSuffix = attribute.type === 'Binary' ? 'BinaryValue' : 'StringValue'
-                return Object.assign(params, {
-                    [`MessageAttribute.${i + 1}.Name`]: name,
-                    [`MessageAttribute.${i + 1}.Value.${valueParameterSuffix}`]: attribute.value,
-                    [`MessageAttribute.${i + 1}.Value.DataType`]: attribute.type
-                })
-            }, {} as Record<string, string>)
-            body = { ...body, ...attributeParameters };
+            const attributeParameters = Object.entries(options.messageAttributes).reduce(
+                (params, [name, attribute], i) => {
+                    const valueParameterSuffix =
+                        attribute.type === 'Binary' ? 'BinaryValue' : 'StringValue'
+                    return Object.assign(params, {
+                        [`MessageAttribute.${i + 1}.Name`]: name,
+                        [`MessageAttribute.${i + 1}.Value.${valueParameterSuffix}`]:
+                            attribute.value,
+                        [`MessageAttribute.${i + 1}.Value.DataType`]: attribute.type,
+                    })
+                },
+                {} as Record<string, string>
+            )
+            body = { ...body, ...attributeParameters }
         }
 
         if (typeof options.delaySeconds !== 'undefined') {
-            body = { ...body, DelaySeconds: options.delaySeconds };
+            body = { ...body, DelaySeconds: options.delaySeconds }
         }
 
         const signedRequest: SignedHTTPRequest = this.signature.sign(
@@ -249,7 +254,7 @@ export interface SendMessageOptions {
      * The message attributes
      */
     messageAttributes?: {
-        [name: string]: { type: 'String' | 'Number' | 'Binary', value: string }
+        [name: string]: { type: 'String' | 'Number' | 'Binary'; value: string }
     }
 
     /**

src/internal/ssm.ts

@@ -12,9 +12,9 @@ import { InvalidSignatureError, SignatureV4 } from './signature'
  * Class allowing to interact with Amazon AWS's Systems Manager service
  */
 export class SystemsManagerClient extends AWSClient {
-    method: HTTPMethod
-    commonHeaders: HTTPHeaders
-    signature: SignatureV4
+    private readonly signature: SignatureV4
+    private readonly method: HTTPMethod
+    private readonly commonHeaders: HTTPHeaders
 
     /**
      * Create a SystemsManagerClient