fix: disable log prettification on AWS

pino-pretty doesn't seem to work at all when sending logs to AWS
CloudWatch. We also never want prettified logs to be in production, so
this protects us against the case where `NODE_ENV` isn't set in an AWS
context.

Author: rowanmanning

packages/logger/lib/logger.js

@@ -69,11 +69,14 @@ const prettificationAvailable = (() => {
 /**
  * Whether log prettification is allowed. We never allow log
  * prettification if the `NODE_ENV` environment variable is
- * set to "production".
+ * set to "production". We also disallow prettification if the
+ * cloud provider is AWS, pino-pretty does not work well with
+ * CloudWatch logs
  *
  * @type {boolean}
  */
-const prettificationAllowed = appInfo.environment !== 'production';
+const prettificationAllowed =
+	appInfo.environment !== 'production' && appInfo.cloudProvider !== 'aws';
 
 /**
  * Class representing a logger.

packages/logger/test/unit/lib/logger.spec.js

@@ -28,6 +28,7 @@ jest.mock('pino-pretty', () => {
 });
 
 jest.mock('@dotcom-reliability-kit/app-info', () => ({
+	cloudProvider: null,
 	environment: 'production'
 }));
 const appInfo = require('@dotcom-reliability-kit/app-info');
@@ -1085,6 +1086,32 @@ describe('@dotcom-reliability-kit/logger/lib/logger', () => {
 			});
 		});
 
+		describe('when pino-pretty is installed and AWS is detected as a cloud provider', () => {
+			beforeEach(() => {
+				jest.mock('pino-pretty', () => 'mock pino pretty');
+				appInfo.cloudProvider = 'aws';
+
+				// We have to reset all modules because the checks for pino-pretty are done
+				// on module load for performance reasons. This resets the cache and reloads
+				// everything with a new environment.
+				jest.isolateModules(() => {
+					Logger = require('../../../lib/logger');
+				});
+
+				pino.mockClear();
+				logger = new Logger();
+			});
+
+			afterEach(() => {
+				jest.unmock('pino-pretty');
+			});
+
+			it('does not configure the created Pino logger with prettification', () => {
+				const pinoOptions = pino.mock.calls[0][0];
+				expect(pinoOptions.transport).toBeUndefined();
+			});
+		});
+
 		describe('when pino-pretty is not installed and the environment is "development"', () => {
 			beforeEach(() => {
 				appInfo.environment = 'development';