Rewrite migration 17 without idb

We ran into issues when doing async operations inside of an IndexedDB
`onupgradeneeded` handler. The errors were ‘The transaction is not active’ or
‘Transaction has finished’. The following documentation confirmed that
transactions are committed/terminated when control returns to the event loop:

Spec
- https://www.w3.org/TR/IndexedDB/#transaction-lifetime-concept
- https://www.w3.org/TR/IndexedDB/#upgrade-transaction-construct

Stack Overflow
- https://stackoverflow.com/a/11059085
- https://stackoverflow.com/a/27338944

Since the initial database migration is so critical, I decided to avoid `idb`
with promise support for IndexedDB for now, but will reconsider using it for
other tasks in the future to improve readability of IndexedDB code.

js/modules/migrations/17/index.js

@@ -1,39 +1,63 @@
-const idb = require('idb');
 const Message = require('../../types/message');
 
 
 exports.run = async (transaction) => {
-  const db = idb.upgradeDBFromTransaction(transaction);
-  const tx = db.transaction;
-  const messagesStore = tx.objectStore('messages');
+  const messagesStore = transaction.objectStore('messages');
 
   console.log('Initialize messages schema version');
-  await exports._initializeMessageSchemaVersion(messagesStore);
+  const numUpgradedMessages = await _initializeMessageSchemaVersion(messagesStore);
+  console.log('Complete messages schema version initialization', { numUpgradedMessages });
 
   console.log('Create index from attachment schema version to attachment');
   messagesStore.createIndex('schemaVersion', 'schemaVersion', { unique: false });
-
-  await db.transaction.complete;
 };
 
-// NOTE: We disable `no-await-in-loop` because we want this migration to happen
-// in sequence and not in parallel:
-// https://eslint.org/docs/rules/no-await-in-loop#when-not-to-use-it
-exports._initializeMessageSchemaVersion = async (messagesStore) => {
-  let cursor = await messagesStore.openCursor();
-  while (cursor) {
-    const message = cursor.value;
-    console.log('Initialize schema version for message:', message.id);
+const _initializeMessageSchemaVersion = messagesStore =>
+  new Promise((resolve, reject) => {
+    const messagePutOperations = [];
 
-    const messageWithSchemaVersion = Message.initializeSchemaVersion(message);
+    const cursorRequest = messagesStore.openCursor();
+    cursorRequest.onsuccess = (event) => {
+      const cursor = event.target.result;
+      const hasMoreData = Boolean(cursor);
+      if (!hasMoreData) {
+        // eslint-disable-next-line more/no-then
+        return Promise.all(messagePutOperations)
+          .then(() => resolve(messagePutOperations.length));
+      }
+
+      const message = cursor.value;
+      const messageWithSchemaVersion = Message.initializeSchemaVersion(message);
+      messagePutOperations.push(new Promise((resolvePut) => {
+        console.log(
+          'Initialize schema version for message:',
+          messageWithSchemaVersion.id
+        );
+
+        resolvePut(putItem(
+          messagesStore,
+          messageWithSchemaVersion,
+          messageWithSchemaVersion.id
+        ));
+      }));
+
+      return cursor.continue();
+    };
+
+    cursorRequest.onerror = event =>
+      reject(event.target.error);
+  });
+
+//    putItem :: IDBObjectStore -> Item -> Key -> Promise Item
+const putItem = (store, item, key) =>
+  new Promise((resolve, reject) => {
     try {
-      // eslint-disable-next-line no-await-in-loop
-      await messagesStore.put(messageWithSchemaVersion, message.id);
+      const request = store.put(item, key);
+      request.onsuccess = event =>
+        resolve(event.target.result);
+      request.onerror = event =>
+        reject(event.target.error);
     } catch (error) {
-      console.log('Failed to put message with initialized schema version:', message.id);
+      reject(error);
     }
-
-    // eslint-disable-next-line no-await-in-loop
-    cursor = await cursor.continue();
-  }
-};
+  });