Speed up app loading by fetching inventory images concurrently

gui.py

@@ -1302,6 +1302,18 @@ def _on_tab_switched(self, event: tk.Event[ttk.Notebook]) -> None:
             # refresh only if we're switching to the tab
             self.refresh()
 
+    def get_status(self, campaign: DropsCampaign) -> tuple[str, str]:
+        if campaign.active:
+            status_text: str = _("gui", "inventory", "status", "active")
+            status_color: str = "green"
+        elif campaign.upcoming:
+            status_text = _("gui", "inventory", "status", "upcoming")
+            status_color = "goldenrod"
+        else:
+            status_text = _("gui", "inventory", "status", "expired")
+            status_color = "red"
+        return (status_text, status_color)
+
     def refresh(self):
         for campaign in self._campaigns:
             # status
@@ -1341,6 +1353,13 @@ async def add_campaign(self, campaign: DropsCampaign) -> None:
             campaign_frame, text=status_text, takefocus=False, foreground=status_color
         )
         status_label.grid(column=1, row=1, sticky="w", padx=4)
+        # NOTE: We have to save the campaign's frame and status before any awaits happen,
+        # otherwise the len(self._campaigns) call may overwrite an existing frame,
+        # if the campaigns are added concurrently.
+        self._campaigns[campaign] = {
+            "frame": campaign_frame,
+            "status": status_label,
+        }
         # Starts / Ends
         MouseOverLabel(
             campaign_frame,
@@ -1415,10 +1434,6 @@ async def add_campaign(self, campaign: DropsCampaign) -> None:
             self._drops[drop.id] = label = MouseOverLabel(drop_frame)
             self.update_progress(drop, label)
             label.grid(column=0, row=1)
-        self._campaigns[campaign] = {
-            "frame": campaign_frame,
-            "status": status_label,
-        }
         if self._manager.tabs.current_tab() == 1:
             self._update_visibility(campaign)
             self._canvas_update()
@@ -1429,18 +1444,6 @@ def clear(self) -> None:
         self._drops.clear()
         self._campaigns.clear()
 
-    def get_status(self, campaign: DropsCampaign) -> tuple[str, str]:
-        if campaign.active:
-            status_text: str = _("gui", "inventory", "status", "active")
-            status_color: str = "green"
-        elif campaign.upcoming:
-            status_text = _("gui", "inventory", "status", "upcoming")
-            status_color = "goldenrod"
-        else:
-            status_text = _("gui", "inventory", "status", "expired")
-            status_color = "red"
-        return (status_text, status_color)
-
     def update_progress(self, drop: TimedDrop, label: MouseOverLabel) -> None:
         # Returns: main text, alt text, text color
         alt_text: str = ''

twitch.py

@@ -1462,25 +1462,37 @@ async def fetch_inventory(self) -> None:
         campaigns.sort(key=lambda c: c.active, reverse=True)
         campaigns.sort(key=lambda c: c.upcoming and c.starts_at or c.ends_at)
         campaigns.sort(key=lambda c: c.linked, reverse=True)
+
         self._drops.clear()
         self.gui.inv.clear()
         self.inventory.clear()
+        self._mnt_triggers.clear()
         switch_triggers: set[datetime] = set()
         next_hour = datetime.now(timezone.utc) + timedelta(hours=1)
-        for i, campaign in enumerate(campaigns, start=1):
-            status_update(
-                _("gui", "status", "adding_campaigns").format(counter=f"({i}/{len(campaigns)})")
-            )
+        # add the campaigns to the internal inventory
+        for campaign in campaigns:
             self._drops.update({drop.id: drop for drop in campaign.drops})
             if campaign.can_earn_within(next_hour):
                 switch_triggers.update(campaign.time_triggers)
-            # NOTE: this fetches pictures from the CDN, so might be slow without a cache
-            await self.gui.inv.add_campaign(campaign)
-            # this is needed here explicitly, because images aren't always fetched
+            self.inventory.append(campaign)
+        # concurrently add the campaigns into the GUI
+        # NOTE: this fetches pictures from the CDN, so might be slow without a cache
+        for i, coro in enumerate(
+            asyncio.as_completed(
+                [
+                    asyncio.create_task(self.gui.inv.add_campaign(campaign))
+                    for campaign in campaigns
+                ]
+            ),
+            start=1,
+        ):
+            status_update(
+                _("gui", "status", "adding_campaigns").format(counter=f"({i}/{len(campaigns)})")
+            )
+            await coro
+            # this is needed here explicitly, because cache reads from disk don't raise this
             if self.gui.close_requested:
                 raise ExitRequest()
-            self.inventory.append(campaign)
-        self._mnt_triggers.clear()
         self._mnt_triggers.extend(sorted(switch_triggers))
         # trim out all triggers that we're already past
         now = datetime.now(timezone.utc)