Better logger formatting

Author: stevebux

internal/helpers/package.json

@@ -1,5 +1,6 @@
 {
   "dependencies": {
+    "pino": "^9.7.0",
     "zod": "^4.1.11"
   },
   "description": "Common helper utilities for NHS Notify Supplier API",

internal/helpers/src/__tests__/logger.test.ts

@@ -0,0 +1,24 @@
+import { createLogger } from "../logger";
+
+describe("createLogger", () => {
+  it("should create a logger with default log level", () => {
+    const logger = createLogger();
+
+    expect(logger.level).toBe("info");
+  });
+
+  it("should create a logger with custom log level", () => {
+    const logger = createLogger({ logLevel: "debug" });
+
+    expect(logger.level).toBe("debug");
+  });
+
+  it("should have expected logging methods", () => {
+    const logger = createLogger();
+
+    expect(typeof logger.info).toBe("function");
+    expect(typeof logger.error).toBe("function");
+    expect(typeof logger.warn).toBe("function");
+    expect(typeof logger.debug).toBe("function");
+  });
+});

internal/helpers/src/index.ts

@@ -7,3 +7,4 @@
 export * from "./version";
 export { default as $Environment } from "./environment";
 export * from "./id-ref";
+export * from "./logger";

internal/helpers/src/logger.ts

@@ -0,0 +1,26 @@
+import pino, { Logger } from "pino";
+
+export type LoggerOptions = {
+  logLevel?: string;
+};
+
+/**
+ * Creates a configured pino logger instance for use across lambdas.
+ *
+ * @param options - Optional configuration for the logger
+ * @param options.logLevel - The log level (defaults to "info")
+ * @returns A configured pino Logger instance
+ */
+export function createLogger(options: LoggerOptions = {}): Logger {
+  const { logLevel = "info" } = options;
+
+  return pino({
+    level: logLevel,
+    formatters: {
+      level: (label) => {
+        return { level: label.toUpperCase() };
+      },
+    },
+    timestamp: () => `,"timestamp":"${new Date(Date.now()).toISOString()}"`,
+  });
+}

lambdas/api-handler/src/config/__tests__/deps.test.ts

@@ -15,14 +15,14 @@ describe("createDependenciesContainer", () => {
     jest.clearAllMocks();
     jest.resetModules();
 
-    // pino
-    jest.mock("pino", () => ({
-      __esModule: true,
-      default: jest.fn(() => ({
+    // @internal/helpers - createLogger
+    jest.mock("@internal/helpers", () => ({
+      createLogger: jest.fn(() => ({
         info: jest.fn(),
         error: jest.fn(),
         warn: jest.fn(),
         debug: jest.fn(),
+        level: "info",
       })),
     }));
 
@@ -49,7 +49,7 @@ describe("createDependenciesContainer", () => {
     // get current mock instances
     const { S3Client } = jest.requireMock("@aws-sdk/client-s3");
     const { SQSClient } = jest.requireMock("@aws-sdk/client-sqs");
-    const pinoMock = jest.requireMock("pino");
+    const { createLogger } = jest.requireMock("@internal/helpers");
     const { LetterRepository, MIRepository } = jest.requireMock(
       "@internal/datastore",
     );
@@ -63,7 +63,7 @@ describe("createDependenciesContainer", () => {
 
     expect(SQSClient).toHaveBeenCalledTimes(1);
 
-    expect(pinoMock.default).toHaveBeenCalledTimes(1);
+    expect(createLogger).toHaveBeenCalledTimes(1);
 
     expect(LetterRepository).toHaveBeenCalledTimes(1);
     const letterRepoCtorArgs = LetterRepository.mock.calls[0];

lambdas/api-handler/src/config/deps.ts

@@ -2,12 +2,13 @@ import { S3Client } from "@aws-sdk/client-s3";
 import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
 import { DynamoDBDocumentClient } from "@aws-sdk/lib-dynamodb";
 import { SQSClient } from "@aws-sdk/client-sqs";
-import pino from "pino";
+import { Logger } from "pino";
 import {
   DBHealthcheck,
   LetterRepository,
   MIRepository,
 } from "@internal/datastore";
+import { createLogger } from "@internal/helpers";
 import { EnvVars, envVars } from "./env";
 
 export type Deps = {
@@ -16,7 +17,7 @@ export type Deps = {
   letterRepo: LetterRepository;
   miRepo: MIRepository;
   dbHealthcheck: DBHealthcheck;
-  logger: pino.Logger;
+  logger: Logger;
   env: EnvVars;
 };
 
@@ -26,7 +27,7 @@ function createDocumentClient(): DynamoDBDocumentClient {
 }
 
 function createLetterRepository(
-  log: pino.Logger,
+  log: Logger,
   environment: EnvVars,
 ): LetterRepository {
   const config = {
@@ -47,7 +48,7 @@ function createDBHealthcheck(environment: EnvVars): DBHealthcheck {
 }
 
 function createMIRepository(
-  log: pino.Logger,
+  log: Logger,
   environment: EnvVars,
 ): MIRepository {
   const config = {
@@ -59,15 +60,7 @@ function createMIRepository(
 }
 
 export function createDependenciesContainer(): Deps {
-  const log = pino({
-    level: envVars.PINO_LOG_LEVEL || "info",
-    formatters: {
-      level: (label) => {
-        return { level: label.toUpperCase() };
-      },
-    },
-    timestamp: () => `,"timestamp":"${new Date(Date.now()).toISOString()}"`,
-  });
+  const log = createLogger({ logLevel: envVars.PINO_LOG_LEVEL });
 
   return {
     s3Client: new S3Client(),

lambdas/upsert-letter/package.json

@@ -3,6 +3,7 @@
     "@aws-sdk/client-dynamodb": "^3.858.0",
     "@aws-sdk/lib-dynamodb": "^3.858.0",
     "@internal/datastore": "*",
+    "@internal/helpers": "*",
     "@nhsdigital/nhs-notify-event-schemas-letter-rendering": "^2.0.1",
     "@nhsdigital/nhs-notify-event-schemas-letter-rendering-v1": "npm:@nhsdigital/nhs-notify-event-schemas-letter-rendering@^1.1.5",
     "@nhsdigital/nhs-notify-event-schemas-supplier-api": "^1.0.8",

lambdas/upsert-letter/src/config/__tests__/deps.test.ts

@@ -10,14 +10,14 @@ describe("createDependenciesContainer", () => {
     jest.clearAllMocks();
     jest.resetModules();
 
-    // pino
-    jest.mock("pino", () => ({
-      __esModule: true,
-      default: jest.fn(() => ({
+    // @internal/helpers - createLogger
+    jest.mock("@internal/helpers", () => ({
+      createLogger: jest.fn(() => ({
         info: jest.fn(),
         error: jest.fn(),
         warn: jest.fn(),
         debug: jest.fn(),
+        level: "info",
       })),
     }));
 
@@ -32,14 +32,14 @@ describe("createDependenciesContainer", () => {
 
   test("constructs deps and wires repository config correctly", async () => {
     // get current mock instances
-    const pinoMock = jest.requireMock("pino");
+    const { createLogger } = jest.requireMock("@internal/helpers");
     const { LetterRepository } = jest.requireMock("@internal/datastore");
 
     // eslint-disable-next-line @typescript-eslint/no-require-imports
     const { createDependenciesContainer } = require("../deps");
     const deps: Deps = createDependenciesContainer();
 
-    expect(pinoMock.default).toHaveBeenCalledTimes(1);
+    expect(createLogger).toHaveBeenCalledTimes(1);
 
     expect(LetterRepository).toHaveBeenCalledTimes(1);
     const letterRepoCtorArgs = LetterRepository.mock.calls[0];

lambdas/upsert-letter/src/config/deps.ts

@@ -1,12 +1,13 @@
 import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
 import { DynamoDBDocumentClient } from "@aws-sdk/lib-dynamodb";
-import pino from "pino";
+import { Logger } from "pino";
 import { LetterRepository } from "@internal/datastore";
+import { createLogger } from "@internal/helpers";
 import { EnvVars, envVars } from "./env";
 
 export type Deps = {
   letterRepo: LetterRepository;
-  logger: pino.Logger;
+  logger: Logger;
   env: EnvVars;
 };
 
@@ -16,7 +17,7 @@ function createDocumentClient(): DynamoDBDocumentClient {
 }
 
 function createLetterRepository(
-  log: pino.Logger,
+  log: Logger,
   // eslint-disable-next-line @typescript-eslint/no-shadow
   envVars: EnvVars,
 ): LetterRepository {
@@ -29,7 +30,7 @@ function createLetterRepository(
 }
 
 export function createDependenciesContainer(): Deps {
-  const log = pino();
+  const log = createLogger();
 
   return {
     letterRepo: createLetterRepository(log, envVars),