make database updating state trackable

data/db.js

@@ -80,6 +80,8 @@ export default class WbDb extends EventTarget {
   #blocked = false;
   /** Whether opening the DB has failed. */
   #failed = false;
+  /** Whether the DB is currently being upgraded. */
+  #upgrading = false;
 
   /** Get the actual database. */
   get db() {
@@ -109,6 +111,11 @@ export default class WbDb extends EventTarget {
     return this.#failed;
   }
 
+  /** Check whether the database is currently being upgraded. */
+  get upgrading() {
+    return this.#upgrading;
+  }
+
   /** Handle the `blocked` event for opening the DB.
    * @param {IDBVersionChangeEvent} event The actual event.
    */
@@ -121,6 +128,10 @@ export default class WbDb extends EventTarget {
    * @param {IDBVersionChangeEvent} event The actual event.
    */
   #handleUpgrade(event) {
+    this.#blocked = false;
+    this.#upgrading = true;
+    this.dispatchEvent(new CustomEvent(WbDb.EVENT_CHANGE));
+
     let {
       oldVersion: old,
       newVersion: now,
@@ -136,6 +147,8 @@ export default class WbDb extends EventTarget {
    */
   #handleError(event) {
     this.#failed = true;
+    this.#blocked = false;
+    this.#upgrading = false;
     this.dispatchEvent(new CustomEvent(WbDb.EVENT_CHANGE));
   }
 
@@ -144,6 +157,7 @@ export default class WbDb extends EventTarget {
    */
   #handleSuccess(event) {
     this.#blocked = false;
+    this.#upgrading = false;
     this.#db = event.target.result;
     this.dispatchEvent(new CustomEvent(WbDb.EVENT_CHANGE));
   }

data/db.test.js

@@ -25,11 +25,13 @@ let inst = null;
  * Uses the `inst` global variable if no `instance` parameter is passed.
  *
  * @param {WbDb=} instance The instance to wait on.
+ * @param {boolean=} anyChange Whether any change is enough (default only open).
  */
-function waitForChange(instance) {
+function waitForChange(instance, anyChange) {
   return new Promise(function(resolve) {
     (instance ?? inst).addEventListener(WbDb.EVENT_CHANGE, function() {
-      resolve();
+      if (anyChange === true || (instance ?? inst).open)
+        resolve();
     });
   });
 }
@@ -99,7 +101,7 @@ export default function() {
       assert.strictEqual(first.db.version, 1, "first instance is version 1");
 
       inst = WbDb.get(true, 2);
-      await waitForChange();
+      await waitForChange(inst, true);
       assert.true(inst.blocked, "second instance blocked");
       assert.false(inst.open, "second instance not open");
       assert.false(inst.failed, "second instance not failed");
@@ -120,9 +122,11 @@ export default function() {
       first.db.close();
 
       let second = WbDb.get(true, 1)
-      await waitForChange(second);
+      await waitForChange(second, true);
-      if (second.blocked)
+      if (second.blocked) {
-        await waitForChange(second);
+        await waitForChange(second, true);
+        assert.true(false, "opening of old db is never blocked");
+      }
 
       assert.false(second.blocked, "second instance not blocked");
       assert.false(second.open, "second instance not open");

data/session_repo.test.js

@@ -22,10 +22,11 @@ let inst = null;
  *
  * @param {WbDb=} instance The instance to wait on.
  */
-function waitForChange(instance) {
+function waitForOpen(instance) {
   return new Promise(function(resolve) {
     (instance ?? inst).addEventListener(WbDb.EVENT_CHANGE, function() {
-      resolve();
+      if ((instance ?? inst).open)
+        resolve();
     });
   });
 }
@@ -59,14 +60,14 @@ export default function() {
 
     QUnit.test("initially no sessions", async function(assert) {
       inst = WbDb.get(true);
-      await waitForChange(inst);
+      await waitForOpen(inst);
       let sessions = await SessionRepo.getAll(inst);
       assert.strictEqual(sessions.length, 0, "no sessions");
     });
 
     QUnit.test("store single session", async function(assert) {
       inst = WbDb.get(true);
-      let req = waitForChange(inst);
+      let req = waitForOpen(inst);
 
       let session = new Session();
       session.ourTeam = "This is us!";
@@ -88,7 +89,7 @@ export default function() {
 
     QUnit.test("store two sessions", async function(assert) {
       inst = WbDb.get(true);
-      let req =  waitForChange(inst);
+      let req = waitForOpen(inst);
 
       let first = new Session();
       first.ourTeam = "Team A";
@@ -130,7 +131,7 @@ export default function() {
 
     QUnit.test("new session reacts to changes", async function(assert) {
       inst = WbDb.get(true);
-      await waitForChange(inst);
+      await waitForOpen(inst);
 
       let session = new Session();
       let id = await SessionRepo.put(session, inst);