Allow original preservation.

react-native/services/FileStore/index.tsx

@@ -1,12 +1,14 @@
-import * as Crypto from 'expo-crypto'
 import * as FileSystem from 'expo-file-system'
 import type { FileStoreInterface } from '../../types/FileStoreInterface'
+import type { UuidGenerator } from '../UuidGenerator'
 
 /**
  * A wrapper around expo-file-system which stores files in a subdirectory of the
  * document directory and provides a mockable interface.
  */
 export class FileStore implements FileStoreInterface {
+  constructor (private readonly uuidGenerator: UuidGenerator) {}
+
   private subdirectoryName: null | string = null
   private loading = false
   private operationsInProgress = 0
@@ -99,7 +101,7 @@ export class FileStore implements FileStoreInterface {
       try {
         this.operationsInProgress++
 
-        const output = Crypto.randomUUID().toLowerCase()
+        const output = this.uuidGenerator.generate()
 
         await FileSystem.moveAsync({
           from: fileUri,
@@ -112,4 +114,27 @@ export class FileStore implements FileStoreInterface {
       }
     }
   }
+
+  async importPreservingOriginal (fileUri: string): Promise<string> {
+    if (this.loading) {
+      throw new Error('The file store is currently loading.')
+    } else if (this.subdirectoryName === null) {
+      throw new Error('The file store is not loaded.')
+    } else {
+      try {
+        this.operationsInProgress++
+
+        const output = this.uuidGenerator.generate()
+
+        await FileSystem.copyAsync({
+          from: fileUri,
+          to: this.generatePath(output)
+        })
+
+        return output
+      } finally {
+        this.operationsInProgress--
+      }
+    }
+  }
 }

react-native/services/FileStore/readme.md

@@ -6,9 +6,9 @@ document directory and provides a mockable interface.
 ## Usage
 
 ```tsx
-import type { FileStore } from "react-native-app-helpers";
+import type { UuidGenerator, FileStore } from "react-native-app-helpers";
 
-const fileStore = new FileStore();
+const fileStore = new FileStore(new UuidGenerator());
 
 await fileStore.load(`example-subdirectory-name`);
 
@@ -24,6 +24,9 @@ fileStore.generatePath(`9dd60263-682d-41b9-bf39-c3a1183da1b1`);
 // `9dd60263-682d-41b9-bf39-c3a1183da1b1`
 await fileStore.import(`example-file-uri`);
 
+// `9dd60263-682d-41b9-bf39-c3a1183da1b1`
+await fileStore.importPreservingOriginal(`example-file-uri`);
+
 fileStore.unload();
 ```