From dfba6bde1efe5b227a9a99bcdab13b9499bc89e7 Mon Sep 17 00:00:00 2001
From: Thomas Ghysels <info@thomasg.be>
Date: Fri, 26 Aug 2022 14:44:09 +0200
Subject: [PATCH] feat: add option to clear cache in @bothrs/translations

---
 packages/translations/README.md    | 23 +++++++++++++++++++++++
 packages/translations/src/index.ts |  3 ++-
 packages/translations/src/types.ts |  2 ++
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/packages/translations/README.md b/packages/translations/README.md
index 4112f74..10fdea5 100644
--- a/packages/translations/README.md
+++ b/packages/translations/README.md
@@ -34,6 +34,7 @@ export function AirtableExample() {
 | -------------- | ------------------------------------------------------- |
 | expirationTime | Time between translation refreshes in ms                |
 | loadPath       | The endpoint from where the translations will be loaded |
+| storagePrefix  | Prefix for the location where the cache is persisted    |
 
 ### Airtable table structure
 
@@ -69,7 +70,29 @@ export function GenericExample() {
 }
 ```
 
+## Refresh translations
+
+If translations change commonly, consider updating the `storagePrefix` to make sure all users are using the latest translations. This prefix acts as a cache-busting mechanism.
+
+```tsx
+import { useTranslations } from '@bothrs/translations'
+import i18next from 'i18next'
+
+export function GenericExample() {
+  const ready = useTranslations({
+    // Increment manually
+    storagePrefix: 'i18n_3_',
+    // Refresh on every app update
+    storagePrefix: 'i18n_' + Constants.manifest?.version + '_',
+  })
+  return <div>{ready ? i18next.t('Ready') : 'Loading'}</div>
+}
+```
+
+## All options
+
 | Name           | Explanation                                             |
 | -------------- | ------------------------------------------------------- |
 | expirationTime | Time between translation refreshes in ms                |
 | loadPath       | The endpoint from where the translations will be loaded |
+| storagePrefix  | Prefix for the location where the cache is persisted    |
diff --git a/packages/translations/src/index.ts b/packages/translations/src/index.ts
index 454ffec..31ed8ec 100644
--- a/packages/translations/src/index.ts
+++ b/packages/translations/src/index.ts
@@ -36,6 +36,7 @@ export function useTranslations(
 }
 
 export function initTranslations({
+  storagePrefix = 'i18n_',
   expirationTime,
   fetchOptions,
   ...options
@@ -54,7 +55,7 @@ export function initTranslations({
     backend: {
       backends: [StorageBackend, MultiloadAdapter],
       backendOptions: [
-        { prefix: 'i18n_', expirationTime },
+        { prefix: storagePrefix, expirationTime },
         { backend: Fetch, backendOption: fetchOptions },
       ],
     },
diff --git a/packages/translations/src/types.ts b/packages/translations/src/types.ts
index ba2defb..eb9fc1e 100644
--- a/packages/translations/src/types.ts
+++ b/packages/translations/src/types.ts
@@ -37,6 +37,8 @@ export interface TranslationRow {
 }
 
 export interface TranslationInitParameters extends InitOptions {
+  /** allows to bust the cache in a declarative way, warning: previous cached versions are kept in storage forever */
+  storagePrefix?: string
   /** expirationTime time between between revalidation intervals, defaults to 1 week */
   expirationTime?: number
   /** Configuration for 'i18next-fetch-backend' */