fix: better db location logic

packages/SwingSet/bin/rekernelize.js

@@ -6,24 +6,58 @@ import 'node-lmdb';
 import '@agoric/babel-standalone';
 import '@agoric/install-ses';
 
+import fs from 'fs';
 import path from 'path';
 import process from 'process';
 
 import bundleSource from '@agoric/bundle-source';
 import { openLMDBSwingStore } from '@agoric/swing-store-lmdb';
 
+function fail(message) {
+  console.error(message);
+  process.exit(1);
+}
+
+function dirContains(dirpath, suffix) {
+  try {
+    const files = fs.readdirSync(dirpath);
+    for (const file of files) {
+      if (file.endsWith(suffix)) {
+        return true;
+      }
+    }
+    return false;
+  } catch (e) {
+    return false;
+  }
+}
+
 async function main() {
   const argv = process.argv.slice(2);
 
   let dbDir = '.';
   if (argv.length > 1) {
-    console.error('usage: rekernelize [DBDIR]');
-    process.exit(1);
+    fail('usage: rekernelize [DBDIR_OR_FILE]');
   } else if (argv[0]) {
     dbDir = argv[0];
   }
 
-  const kernelStateDBDir = path.join(dbDir, 'swingset-kernel-state');
+  let kernelStateDBDir;
+  const dbSuffix = '.mdb';
+  if (dbDir.endsWith(dbSuffix)) {
+    kernelStateDBDir = path.dirname(dbDir);
+  } else if (dirContains(dbDir, dbSuffix)) {
+    kernelStateDBDir = dbDir;
+  } else {
+    kernelStateDBDir = path.join(dbDir, 'swingset-kernel-state');
+    if (!dirContains(kernelStateDBDir, dbSuffix)) {
+      kernelStateDBDir = null;
+    }
+  }
+  if (!kernelStateDBDir) {
+    fail(`can't find a database at ${dbDir}`);
+  }
+
   const swingStore = openLMDBSwingStore(kernelStateDBDir);
   const kvStore = swingStore.kvStore;
   assert(kvStore.get('initialized'), 'kernel store not initialized');