Allow custom json replacer function - addresses issues #46

src/buffer-manager.ts

@@ -94,7 +94,7 @@ const send = async (lines: LogDNALogLine[]) => {
         Authorization: `Basic ${btoa(`${opts.ingestionKey}:`)}`,
         'Content-Type': 'application/json',
       },
-      body: utils.stringify({ lines }),
+      body: utils.stringify({ lines }, opts.jsonReplacer),
     });
 
     if (response.ok) {

src/capture.ts

@@ -57,7 +57,7 @@ const generateLogLine = ({ level = 'log', message, lineContext = {}, errorContex
   process({
     timestamp: Math.floor(Date.now() / 1000),
     app: opts.app || window.location.host,
-    line: typeof data.message === 'string' ? data.message : utils.stringify(data.message),
+    line: typeof data.message === 'string' ? data.message : utils.stringify(data.message, opts.jsonReplacer),
     level: data.level,
     meta: {
       sessionId: getSessionId(),

src/logdna.d.ts

@@ -1,7 +1,7 @@
 import { GlobalErrorHandlerPlugin } from './plugins/global-handler';
-declare module 'logdna-browser-2' { }
+declare module 'logdna-browser-2' {}
 
-interface LogDNAMethods { }
+interface LogDNAMethods {}
 
 // This is fallback to 3rd party plugin methods
 // Until TS has better Module Augmentation without
@@ -54,6 +54,7 @@ export type LogDNABrowserOptions = {
   ingestionKey?: string;
   hooks?: HooksOption;
   internalErrorLogger?: Function;
+  jsonReplacer?: (key: string, value: any) => any | undefined;
 };
 
 export type LineContext = object;

src/utils.ts

@@ -1,5 +1,6 @@
 import safeStringify from 'fast-safe-stringify';
 import { HOSTNAME_CHECK, DEFAULT_TAG, SESSION_SCORE_KEY } from './constants';
+import { getOptions } from './init';
 
 import { Tags } from './logdna';
 
@@ -17,7 +18,7 @@ const parseTags = (tags: Tags = []) => {
   return [DEFAULT_TAG, ...tags].filter(tag => tag !== '').join(',');
 };
 
-const stringify = (obj: unknown) => safeStringify(obj);
+const stringify = (obj: unknown, replacer?: ((key: string, value: any) => any) | undefined) => safeStringify(obj, replacer);
 
 const getStackTrace = () => {
   const stack = new Error().stack || '';
@@ -48,7 +49,7 @@ const _randomBetween = (min: number, max: number) => {
 const backOffWithJitter = (base: number, cap: number, lastSleep: number) => Math.min(cap, _randomBetween(base, lastSleep * 3));
 
 const jsonByteSize = (obj: unknown) => {
-  const stringified = stringify(obj);
+  const stringified = stringify(obj, getOptions().jsonReplacer);
   if (window.TextEncoder) {
     return new TextEncoder().encode(stringified).length;
   }

tests/init.spec.ts

@@ -54,6 +54,17 @@ describe('init.ts', () => {
       expect(addDefaultPlugins).toHaveBeenCalled();
       expect(addPluginMethods).toHaveBeenCalled();
     });
+
+    it('should add the JSON replacer', () => {
+      let jsonReplacer = (key: string, value: any) => {
+        if (key === 'password') {
+          return '[redacted]';
+        }
+        return value;
+      };
+      config(INGESTION_KEY, { jsonReplacer });
+      expect(getOptions().jsonReplacer).toEqual(jsonReplacer);
+    });
   });
 
   describe('init', () => {

tests/utils.spec.ts

@@ -31,6 +31,19 @@ describe('Utils', () => {
       };
       expect(utils.stringify(encode)).toEqual('{"data":{"obj":{"obj":"[Circular]"}}}');
     });
+    it('should properly use the JSON replacer function', () => {
+      let obj: any = {
+        email: '[email protected]',
+        password: 'SuperSecretPassword',
+      };
+      let jsonReplacer = (key: string, value: any) => {
+        if (key === 'password') {
+          return '[redacted]';
+        }
+        return value;
+      };
+      expect(utils.stringify(obj, jsonReplacer)).toEqual('{"email":"[email protected]","password":"[redacted]"}');
+    });
   });
 
   describe('jsonByteSize', () => {