From 418da1ba8b3a6639921f3f85e214d46f0fedb305 Mon Sep 17 00:00:00 2001
From: Ben White <ben@posthog.com>
Date: Mon, 26 Aug 2024 13:53:22 +0100
Subject: [PATCH 1/2] Added flag for historical migration

---
 posthog-core/src/index.ts | 8 +++++++-
 posthog-core/src/types.ts | 2 ++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/posthog-core/src/index.ts b/posthog-core/src/index.ts
index 2a49f266..edf9032f 100644
--- a/posthog-core/src/index.ts
+++ b/posthog-core/src/index.ts
@@ -61,6 +61,7 @@ export abstract class PostHogCoreStateless {
   private captureMode: 'form' | 'json'
   private removeDebugCallback?: () => void
   private disableGeoip: boolean = true
+  private historicalMigration: boolean = false
   public disabled = false
 
   private defaultOptIn: boolean = true
@@ -106,6 +107,7 @@ export abstract class PostHogCoreStateless {
     this.featureFlagsRequestTimeoutMs = options?.featureFlagsRequestTimeoutMs ?? 3000 // 3 seconds
     this.disableGeoip = options?.disableGeoip ?? true
     this.disabled = options?.disabled ?? false
+    this.historicalMigration = options?.historicalMigration ?? false
     // Init promise allows the derived class to block calls until it is ready
     this._initPromise = Promise.resolve()
     this._isInitialized = true
@@ -573,12 +575,16 @@ export abstract class PostHogCoreStateless {
       this.setPersistedProperty<PostHogQueueItem[]>(PostHogPersistedProperty.Queue, refreshedQueue.slice(items.length))
     }
 
-    const data = {
+    const data: Record<string, any> = {
       api_key: this.apiKey,
       batch: messages,
       sent_at: currentISOTime(),
     }
 
+    if (this.historicalMigration) {
+      data.historical_migration = true
+    }
+
     const payload = JSON.stringify(data)
 
     const url =
diff --git a/posthog-core/src/types.ts b/posthog-core/src/types.ts
index 1bcf5caa..7dc09816 100644
--- a/posthog-core/src/types.ts
+++ b/posthog-core/src/types.ts
@@ -39,6 +39,8 @@ export type PostHogCoreOptions = {
   /** Whether to post events to PostHog in JSON or compressed format. Defaults to 'form' */
   captureMode?: 'json' | 'form'
   disableGeoip?: boolean
+  /** Special flag to indicate ingested data is for a historical migration. */
+  historicalMigration?: boolean
 }
 
 export enum PostHogPersistedProperty {

From 697f33e0ee8a263b15d6d022454947d29d23da23 Mon Sep 17 00:00:00 2001
From: Ben White <ben@posthog.com>
Date: Mon, 26 Aug 2024 13:54:41 +0100
Subject: [PATCH 2/2] Updated packages

---
 posthog-node/CHANGELOG.md | 5 +++++
 posthog-node/package.json | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/posthog-node/CHANGELOG.md b/posthog-node/CHANGELOG.md
index a09d5c73..a3385f24 100644
--- a/posthog-node/CHANGELOG.md
+++ b/posthog-node/CHANGELOG.md
@@ -1,8 +1,13 @@
 # Next
 
+# 4.2.0 - 2024-08-26
+
+1. Added `historicalMigration` option for use in tools that are migrating large data to PostHog
+
 # 4.1.1 - 2024-08-20
 
 1. Local evaluation returns correct results on `undefined/null` values
+
 # 4.1.0 - 2024-08-14
 
 1. chore: change host to new address.
diff --git a/posthog-node/package.json b/posthog-node/package.json
index d029dc2e..ad304d43 100644
--- a/posthog-node/package.json
+++ b/posthog-node/package.json
@@ -1,6 +1,6 @@
 {
   "name": "posthog-node",
-  "version": "4.1.1",
+  "version": "4.2.0",
   "description": "PostHog Node.js integration",
   "repository": {
     "type": "git",