enables schema saving in db, initial refactor of db schema for revisions

lib/secret/index.ts

@@ -15,9 +15,13 @@ export class DHSecretClient {
    * @param dhBaseUri uri for hosted Dragon's Hoard instance
    * @param cacheDir path to cache dir
    */
-  constructor(private dhBaseUri: string, private cacheDir: string) {
+  constructor(
+    private dhBaseUri: string,
+    private cacheDir: string,
+  ) {
     this.cacheLocation = this.cacheDir.trim().replace(/\/^/, "") + "/.dh_cache";
     mkdirSync(this.cacheDir, { recursive: true });
+
     this.readDiskCache();
     this.token = this.fetchToken();
   }
@@ -42,12 +46,13 @@ export class DHSecretClient {
   }
 
   private readDiskCache() {
-    const cache = readFileSync(this.cacheLocation, "utf-8");
-
-    if (!cache) {
+    try {
+      const cache = readFileSync(this.cacheLocation, "utf-8");
+      this.cache = JSON.parse(cache || "{}");
+    } catch {
       this.cache = {};
-      this.writeDiskCache();
-    } else this.cache = JSON.parse(cache || "{}");
+      this.writeDiskCache().then(this.readDiskCache);
+    }
   }
   private async writeDiskCache() {
     await writeFile(this.cacheLocation, JSON.stringify(this.cache), "utf-8");