Merge pull request #12 from Randomblock1/perf/qpdf-singleton-2438142539747209253

⚡ Optimize QPDF WASM initialization

Author: Randomblock1

src/lib/qpdf.ts

@@ -0,0 +1,29 @@
+import createModule, { type QpdfInstance } from '@neslinesli93/qpdf-wasm';
+import wasmUrl from '@neslinesli93/qpdf-wasm/dist/qpdf.wasm?url';
+
+let qpdfPromise: Promise<QpdfInstance> | null = null;
+
+export function getQpdf(): Promise<QpdfInstance> {
+    if (!qpdfPromise) {
+        qpdfPromise = createModule({
+            locateFile: () => wasmUrl,
+            // @ts-expect-error missing from types
+            noInitialRun: true,
+            preRun: [
+                (module: QpdfInstance) => {
+                    if (module.FS) {
+                        try {
+                            module.FS.mkdir('/input');
+                            module.FS.mkdir('/output');
+                        } catch (e) {
+                            console.warn('Error creating directories:', e);
+                        }
+                    }
+                }
+            ]
+        });
+    }
+    return qpdfPromise;
+}
+
+export type { QpdfInstance };

src/routes/+page.svelte

@@ -5,8 +5,8 @@
         faCircleExclamation,
         faTriangleExclamation
     } from '@fortawesome/free-solid-svg-icons';
-    import createModule, { type QpdfInstance } from '@neslinesli93/qpdf-wasm';
-    import wasmUrl from '@neslinesli93/qpdf-wasm/dist/qpdf.wasm?url';
+    import { type QpdfInstance } from '@neslinesli93/qpdf-wasm';
+    import { getQpdf } from '$lib/qpdf';
 
     import { onMount } from 'svelte';
     import { fileListFromFileArray, convertFileHandlesToFileList, download } from '$lib/file-utils';
@@ -21,23 +21,7 @@
     onMount(async () => {
         // Initialize QPDF WASM module
         try {
-            qpdf = await createModule({
-                locateFile: () => wasmUrl,
-                // @ts-expect-error missing from types
-                noInitialRun: true,
-                preRun: [
-                    (module: QpdfInstance) => {
-                        if (module.FS) {
-                            try {
-                                module.FS.mkdir('/input');
-                                module.FS.mkdir('/output');
-                            } catch (e) {
-                                console.warn('Error creating directories:', e);
-                            }
-                        }
-                    }
-                ]
-            });
+            qpdf = await getQpdf();
             console.log('QPDF WASM module initialized successfully');
         } catch (error) {
             console.error('Failed to initialize QPDF WASM module:', error);

src/routes/decrypt/+page.svelte

@@ -1,8 +1,8 @@
 <script lang="ts">
     import { FontAwesomeIcon } from '@fortawesome/svelte-fontawesome';
     import { faInfoCircle } from '@fortawesome/free-solid-svg-icons';
-    import createModule, { type QpdfInstance } from '@neslinesli93/qpdf-wasm';
-    import wasmUrl from '@neslinesli93/qpdf-wasm/dist/qpdf.wasm?url';
+    import { type QpdfInstance } from '@neslinesli93/qpdf-wasm';
+    import { getQpdf } from '$lib/qpdf';
 
     import { onMount } from 'svelte';
     import { fileListFromFileArray, convertFileHandlesToFileList, download } from '$lib/file-utils';
@@ -15,23 +15,7 @@
     onMount(async () => {
         // Initialize QPDF WASM module
         try {
-            qpdf = await createModule({
-                locateFile: () => wasmUrl,
-                // @ts-expect-error missing from types
-                noInitialRun: true,
-                preRun: [
-                    (module: QpdfInstance) => {
-                        if (module.FS) {
-                            try {
-                                module.FS.mkdir('/input');
-                                module.FS.mkdir('/output');
-                            } catch (e) {
-                                console.warn('Error creating directories:', e);
-                            }
-                        }
-                    }
-                ]
-            });
+            qpdf = await getQpdf();
             console.log('QPDF WASM module initialized successfully');
         } catch (error) {
             console.error('Failed to initialize QPDF WASM module:', error);