(core) Prevent logging pointless errors about attachments and data size on shutdown

Summary: As suggested in https://grist.slack.com/archives/CR8HZ4P9V/p1652365399661569?thread_ts=1652364998.893169&cid=CR8HZ4P9V, check if DocStorage is initialized before trying to use it when shutting down, to avoid noisy logging of errors about removing attachments and updating data size.

Test Plan: Tested manually that errors early in loadDoc caused logging of errors about attachments/data size before the changed, but not after.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D3522

app/server/lib/ActiveDoc.ts

@@ -485,6 +485,9 @@ export class ActiveDoc extends EventEmitter {
       // We'll defer syncing usage until everything is calculated.
       const usageOptions = {syncUsageToDatabase: false, broadcastUsageToClients: false};
 
+      // This cleanup requires docStorage, which may have failed to start up.
+      // We don't want to log pointless errors in that case.
+      if (this.docStorage.isInitialized()) {
         // Remove expired attachments, i.e. attachments that were soft deleted a while ago. This
         // needs to happen periodically, and doing it here means we can guarantee that it happens
         // even if the doc is only ever opened briefly, without having to slow down startup.
@@ -504,6 +507,7 @@ export class ActiveDoc extends EventEmitter {
         } catch (e) {
           this._log.error(docSession, "Failed to update data size", e);
         }
+      }
 
       this._syncDocUsageToDatabase(true);
 

app/server/lib/DocStorage.ts

@@ -674,6 +674,10 @@ export class DocStorage implements ISQLiteDB, OnDemandStorage {
     // Note that we don't call _updateMetadata() as there are no metadata tables yet anyway.
   }
 
+  public isInitialized(): boolean {
+    return Boolean(this._db);
+  }
+
   /**
    * Initializes the database with proper settings.
    */