Merge pull request #83 from axiomhq/islam/dx-391-add-log-level-to-nex…

…t-axiom

configurable log levels per logger instance

__tests__/logLevels.test.ts

@@ -0,0 +1,47 @@
+/**
+ * @jest-environment jsdom
+ */
+// set axiom env vars before importing logger
+process.env.AXIOM_INGEST_ENDPOINT = 'https://example.co/api/test';
+process.env.AXIOM_LOG_LEVEL = 'error';
+import { log, Logger } from '../src/logger';
+
+jest.useFakeTimers();
+
+test('log levels', async () => {
+  global.fetch = jest.fn() as jest.Mock;
+
+  log.info('test');
+  await log.flush();
+  expect(fetch).toHaveBeenCalledTimes(0);
+
+  // test overriding log level per logger
+  let logger = new Logger({}, null, false, 'frontend', 'error');
+  logger.debug('hello');
+  logger.info('hello');
+  logger.warn('hello');
+  await logger.flush();
+  expect(fetch).toHaveBeenCalledTimes(0);
+
+  logger = new Logger({}, null, false, 'frontend', 'warn');
+  logger.info('hello');
+  logger.debug('hello');
+  await logger.flush();
+  expect(fetch).toHaveBeenCalledTimes(0);
+
+  logger = new Logger({}, null, false, 'frontend', 'info');
+  logger.debug('hello');
+  await logger.flush();
+  expect(fetch).toHaveBeenCalledTimes(0);
+
+  logger = new Logger({}, null, false, 'frontend', 'error');
+  logger.warn('warn');
+  logger.error('error');
+  await logger.flush();
+  expect(fetch).toHaveBeenCalledTimes(1);
+
+  logger = new Logger({}, null, false, 'frontend', 'debug');
+  logger.warn('hello');
+  await logger.flush();
+  expect(fetch).toHaveBeenCalledTimes(2);
+});

src/logger.ts

@@ -3,6 +3,7 @@ import { NetlifyInfo } from './platform/netlify';
 import { isNoPrettyPrint, throttle } from './shared';
 
 const url = config.getLogsEndpoint();
+const LOG_LEVEL = process.env.AXIOM_LOG_LEVEL || 'debug';
 
 export interface LogEvent {
   level: string;
@@ -15,6 +16,13 @@ export interface LogEvent {
   netlify?: NetlifyInfo;
 }
 
+export enum LogLevel {
+  debug = 0,
+  info = 1,
+  warn = 2,
+  error = 3,
+}
+
 export interface RequestReport {
   startTime: number;
   statusCode?: number;
@@ -38,13 +46,17 @@ export class Logger {
   public logEvents: LogEvent[] = [];
   throttledSendLogs = throttle(this.sendLogs, 1000);
   children: Logger[] = [];
+  public logLevel: string;
 
   constructor(
     private args: { [key: string]: any } = {},
     private req: RequestReport | null = null,
     private autoFlush: Boolean = true,
-    public source: 'frontend' | 'lambda' | 'edge' = 'frontend'
-  ) {}
+    public source: 'frontend' | 'lambda' | 'edge' = 'frontend',
+    logLevel?: string
+  ) {
+    this.logLevel = logLevel || LOG_LEVEL || 'debug';
+  }
 
   debug = (message: string, args: { [key: string]: any } = {}) => {
     this._log('debug', message, args);
@@ -70,7 +82,11 @@ export class Logger {
   };
 
   _log = (level: string, message: string, args: { [key: string]: any } = {}) => {
+    if (LogLevel[level] < LogLevel[this.logLevel]) {
+      return;
+    }
     const logEvent: LogEvent = { level, message, _time: new Date(Date.now()).toISOString(), fields: this.args || {} };
+
     // check if passed args is an object, if its not an object, add it to fields.args
     if (typeof args === 'object' && args !== null && Object.keys(args).length > 0) {
       logEvent.fields = { ...logEvent.fields, ...args };