fix: check if window is available before using on web env

posthog-web/src/context.ts

@@ -1,9 +1,9 @@
 import { utils } from '../../posthog-core'
 import { version } from '../package.json'
 
-export function getContext(window: Window): any {
+export function getContext(window: Window | undefined): any {
   let context = {}
-  if (window.navigator) {
+  if (window && window.navigator) {
     const userAgent = window.navigator.userAgent
     context = {
       ...context,
@@ -21,6 +21,7 @@ export function getContext(window: Window): any {
       $screen_dpr: window.devicePixelRatio,
     }
   }
+
   context = {
     ...context,
     $lib: 'js',
@@ -114,7 +115,10 @@ function browserVersion(userAgent: string, vendor: string, opera: boolean): numb
   return parseFloat(matches[matches.length - 2])
 }
 
-function os(window: Window): string {
+function os(window: Window | undefined): string {
+  if (!window || !window.navigator) {
+    return ''
+  }
   const a = window.navigator.userAgent
   if (/Windows/i.test(a)) {
     if (/Phone/.test(a) || /WPDesktop/.test(a)) {

posthog-web/src/posthog-web.ts

@@ -19,14 +19,20 @@ export class PostHog extends PostHogCore {
 
     // posthog-js stores options in one object on
     this._storageKey = options?.persistence_name ? `ph_${options.persistence_name}` : `ph_${apiKey}_posthog`
-    this._storage = getStorage(options?.persistence || 'localStorage', window)
+
+    this._storage = getStorage(options?.persistence || 'localStorage', this._getWindow())
     this.setupBootstrap(options)
 
     if (options?.preloadFeatureFlags !== false) {
       this.reloadFeatureFlags()
     }
   }
 
+  _getWindow(): Window | undefined {
+    const _window: Window | undefined = typeof window !== 'undefined' ? window : undefined
+    return _window
+  }
+
   getPersistedProperty<T>(key: PostHogPersistedProperty): T | undefined {
     if (!this._storageCache) {
       this._storageCache = JSON.parse(this._storage.getItem(this._storageKey) || '{}') || {}
@@ -50,6 +56,9 @@ export class PostHog extends PostHogCore {
   }
 
   fetch(url: string, options: PostHogFetchOptions): Promise<PostHogFetchResponse> {
+    // TODO: what to do here?
+    // should we move this to core? https://github.com/PostHog/posthog-js-lite/blob/main/posthog-node/src/fetch.ts
+    // and reuse it here? if window isn't available?
     return window.fetch(url, options)
   }
 
@@ -68,7 +77,7 @@ export class PostHog extends PostHogCore {
   getCommonEventProperties(): any {
     return {
       ...super.getCommonEventProperties(),
-      ...getContext(window),
+      ...getContext(this._getWindow()),
     }
   }
 }

posthog-web/src/storage.ts

@@ -93,9 +93,6 @@ const createStorageLike = (store: any): PostHogStorage => {
 }
 
 const checkStoreIsSupported = (storage: PostHogStorage, key = '__mplssupport__'): boolean => {
-  if (!window) {
-    return false
-  }
   try {
     const val = 'xyz'
     storage.setItem(key, val)