fix: gracefully handle missing SQLite FTS5 on Windows (#65)

Author: harlan-zw

.github/logos/logo-mark.svg

@@ -1,4 +1,4 @@
-<h1>skilld</h1>
+<h1><a href="https://skilld.dev"><img src=".github/logos/logo-mark.svg" alt="" width="28" height="28" valign="middle"></a> skilld</h1>
 
 [![npm version](https://img.shields.io/npm/v/skilld?color=yellow)](https://npmjs.com/package/skilld)
 [![npm downloads](https://img.shields.io/npm/dm/skilld?color=yellow)](https://npm.chart.dev/skilld)

README.md

@@ -7,7 +7,7 @@ packages:
 overrides:
   global-agent: ^4.1.3
 catalog:
-  '@mariozechner/pi-ai': ^0.63.1
+  '@mariozechner/pi-ai': ^0.64.0
   '@mdream/crawl': ^1.0.3
   '@types/semver': ^7.7.1
   bumpp: ^11.0.1
@@ -36,7 +36,7 @@ catalogs:
     mlly: ^1.8.2
     oxc-parser: ^0.121.0
     p-limit: ^7.3.0
-    sqlite-vec: ^0.1.7
+    sqlite-vec: ^0.1.8
     tinyglobby: ^0.2.15
     unist-util-visit: ^5.1.0
   dev-build:

pnpm-lock.yaml

@@ -6,15 +6,47 @@ export type { ChunkEntity, Document, IndexConfig, IndexPhase, IndexProgress, Sea
 type RetrivInstance = Awaited<ReturnType<typeof getDb>>
 
 export class SearchDepsUnavailableError extends Error {
-  constructor(cause: unknown) {
-    super('Search dependencies unavailable (sqlite-vec or retriv not installed). Search indexing skipped.')
+  constructor(cause: unknown, message?: string) {
+    super(message ?? 'Search dependencies unavailable (sqlite-vec or retriv not installed). Search indexing skipped.')
     this.name = 'SearchDepsUnavailableError'
     this.cause = cause
   }
 }
 
+let _fts5Available: boolean | null = null
+
+/**
+ * Probe whether SQLite FTS5 module is available.
+ * Windows Node.js binaries often ship without FTS5 compiled in.
+ */
+function checkFts5(): boolean {
+  if (_fts5Available !== null)
+    return _fts5Available
+  const nodeSqlite = globalThis.process?.getBuiltinModule?.('node:sqlite') as typeof import('node:sqlite') | undefined
+  if (!nodeSqlite) {
+    _fts5Available = false
+    return false
+  }
+  const db = new nodeSqlite.DatabaseSync(':memory:')
+  try {
+    db.exec('CREATE VIRTUAL TABLE _fts5_probe USING fts5(content)')
+    db.exec('DROP TABLE _fts5_probe')
+    _fts5Available = true
+  }
+  catch {
+    _fts5Available = false
+  }
+  finally {
+    db.close()
+  }
+  return _fts5Available
+}
+
 // Dynamic imports: retriv/chunkers/auto eagerly loads typescript which may not be installed (e.g. npx)
 export async function getDb(config: Pick<IndexConfig, 'dbPath'>) {
+  if (!checkFts5())
+    throw new SearchDepsUnavailableError(new Error('FTS5 module not available'), 'SQLite FTS5 module not available. Search indexing skipped. On Windows, run from WSL where FTS5 is included.')
+
   let createRetriv, autoChunker, sqliteMod, sqliteVec, transformersJs, cachedEmbeddings
   try {
     ;([