impl sequential id plugins (#819)

Also introduce a new kind of plugin: event processor

packages/rrweb/rollup.config.js

@@ -93,6 +93,16 @@ const baseConfigs = [
     name: 'rrwebConsoleReplay',
     pathFn: toPluginPath('console', 'replay'),
   },
+  {
+    input: './src/plugins/sequential-id/record/index.ts',
+    name: 'rrwebSequentialIdRecord',
+    pathFn: toPluginPath('sequential-id', 'record'),
+  },
+  {
+    input: './src/plugins/sequential-id/replay/index.ts',
+    name: 'rrwebSequentialIdReplay',
+    pathFn: toPluginPath('sequential-id', 'replay'),
+  },
 ];
 
 let configs = [];

packages/rrweb/src/plugins/sequential-id/record/index.ts

@@ -0,0 +1,31 @@
+import { RecordPlugin } from '../../../types';
+
+export type SequentialIdOptions = {
+  key: string;
+};
+
+const defaultOptions: SequentialIdOptions = {
+  key: '_sid',
+};
+
+export const PLUGIN_NAME = 'rrweb/sequential-id@1';
+
+export const getRecordSequentialIdPlugin: (
+  options?: Partial<SequentialIdOptions>,
+) => RecordPlugin = (options) => {
+  const _options = options
+    ? Object.assign({}, defaultOptions, options)
+    : defaultOptions;
+  let id = 0;
+
+  return {
+    name: PLUGIN_NAME,
+    eventProcessor(event) {
+      Object.assign(event, {
+        [_options.key]: ++id,
+      });
+      return event;
+    },
+    options: _options,
+  };
+};

packages/rrweb/src/plugins/sequential-id/replay/index.ts

@@ -0,0 +1,39 @@
+import type { SequentialIdOptions } from '../record';
+import { ReplayPlugin, eventWithTime } from '../../../types';
+
+type Options = SequentialIdOptions & {
+  warnOnMissingId: boolean;
+};
+
+const defaultOptions: Options = {
+  key: '_sid',
+  warnOnMissingId: true,
+};
+
+export const getReplaySequentialIdPlugin: (
+  options?: Partial<Options>,
+) => ReplayPlugin = (options) => {
+  const { key, warnOnMissingId } = options
+    ? Object.assign({}, defaultOptions, options)
+    : defaultOptions;
+  let currentId = 1;
+
+  return {
+    handler(event: eventWithTime) {
+      if (key in event) {
+        const id = ((event as unknown) as Record<string, number>)[key];
+        if (id !== currentId) {
+          console.error(
+            `[sequential-id-plugin]: expect to get an id with value "${currentId}", but got "${id}"`,
+          );
+        } else {
+          currentId++;
+        }
+      } else if (warnOnMissingId) {
+        console.warn(
+          `[sequential-id-plugin]: failed to get id in key: "${key}"`,
+        );
+      }
+    },
+  };
+};

packages/rrweb/src/record/index.ts

@@ -122,6 +122,17 @@ function record<T = eventWithTime>(
 
   let lastFullSnapshotEvent: eventWithTime;
   let incrementalSnapshotCount = 0;
+  const eventProcessor = (e: eventWithTime): T => {
+    for (const plugin of plugins || []) {
+      if (plugin.eventProcessor) {
+        e = plugin.eventProcessor(e);
+      }
+    }
+    if (packFn) {
+      e = (packFn(e) as unknown) as eventWithTime;
+    }
+    return (e as unknown) as T;
+  };
   wrappedEmit = (e: eventWithTime, isCheckout?: boolean) => {
     if (
       mutationBuffers[0]?.isFrozen() &&
@@ -136,7 +147,7 @@ function record<T = eventWithTime>(
       mutationBuffers.forEach((buf) => buf.unfreeze());
     }
 
-    emit(((packFn ? packFn(e) : e) as unknown) as T, isCheckout);
+    emit(eventProcessor(e), isCheckout);
     if (e.type === EventType.FullSnapshot) {
       lastFullSnapshotEvent = e;
       incrementalSnapshotCount = 0;
@@ -417,8 +428,10 @@ function record<T = eventWithTime>(
           shadowDomManager,
           canvasManager,
           plugins:
-            plugins?.map((p) => ({
+            plugins
-              observer: p.observer,
+              ?.filter((p) => p.observer)
+              ?.map((p) => ({
+                observer: p.observer!,
                 options: p.options,
                 callback: (payload: object) =>
                   wrappedEmit(

packages/rrweb/src/types.ts

@@ -205,7 +205,8 @@ export type SamplingStrategy = Partial<{
 
 export type RecordPlugin<TOptions = unknown> = {
   name: string;
-  observer: (cb: Function, win: IWindow, options: TOptions) => listenerHandler;
+  observer?: (cb: Function, win: IWindow, options: TOptions) => listenerHandler;
+  eventProcessor?: <TExtend>(event: eventWithTime) => eventWithTime & TExtend;
   options: TOptions;
 };
 

packages/rrweb/typings/plugins/sequential-id/record/index.d.ts

@@ -0,0 +1,6 @@
+import { RecordPlugin } from '../../../types';
+export declare type SequentialIdOptions = {
+    key: string;
+};
+export declare const PLUGIN_NAME = "rrweb/sequential-id@1";
+export declare const getRecordSequentialIdPlugin: (options?: Partial<SequentialIdOptions>) => RecordPlugin;

packages/rrweb/typings/plugins/sequential-id/replay/index.d.ts

@@ -0,0 +1,7 @@
+import type { SequentialIdOptions } from '../record';
+import { ReplayPlugin } from '../../../types';
+declare type Options = SequentialIdOptions & {
+    warnOnMissingId: boolean;
+};
+export declare const getReplaySequentialIdPlugin: (options?: Partial<Options>) => ReplayPlugin;
+export {};

packages/rrweb/typings/types.d.ts

@@ -128,7 +128,8 @@ export declare type SamplingStrategy = Partial<{
 }>;
 export declare type RecordPlugin<TOptions = unknown> = {
     name: string;
-    observer: (cb: Function, win: IWindow, options: TOptions) => listenerHandler;
+    observer?: (cb: Function, win: IWindow, options: TOptions) => listenerHandler;
+    eventProcessor?: <TExtend>(event: eventWithTime) => eventWithTime & TExtend;
     options: TOptions;
 };
 export declare type recordOptions<T> = {