From 8d69b73c9e57cb772156c19770c22ca196704e44 Mon Sep 17 00:00:00 2001
From: Hugo Osvaldo Barrera <hugo@barrera.io>
Date: Tue, 22 Jun 2021 00:50:40 +0200
Subject: [PATCH] Fetch displaynames asynchronously

---
 vdirsyncer/cli/__init__.py |  4 +---
 vdirsyncer/cli/config.py   |  4 +++-
 vdirsyncer/cli/discover.py | 46 +++++++++++++++++++++-----------------
 3 files changed, 30 insertions(+), 24 deletions(-)

diff --git a/vdirsyncer/cli/__init__.py b/vdirsyncer/cli/__init__.py
index 2d914d3..c1db199 100644
--- a/vdirsyncer/cli/__init__.py
+++ b/vdirsyncer/cli/__init__.py
@@ -211,11 +211,9 @@ def discover(ctx, pairs, list):
         conn = aiohttp.TCPConnector(limit_per_host=16)
 
         for pair_name in pairs or config.pairs:
-            pair = config.get_pair(pair_name)
-
             await discover_collections(
                 status_path=config.general["status_path"],
-                pair=pair,
+                pair=config.get_pair(pair_name),
                 from_cache=False,
                 list_collections=list,
                 connector=conn,
diff --git a/vdirsyncer/cli/config.py b/vdirsyncer/cli/config.py
index 40833c4..59e7c45 100644
--- a/vdirsyncer/cli/config.py
+++ b/vdirsyncer/cli/config.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 import json
 import os
 import string
@@ -206,7 +208,7 @@ class Config:
         else:
             return expand_fetch_params(args)
 
-    def get_pair(self, pair_name):
+    def get_pair(self, pair_name: str) -> PairConfig:
         try:
             return self.pairs[pair_name]
         except KeyError as e:
diff --git a/vdirsyncer/cli/discover.py b/vdirsyncer/cli/discover.py
index 877a10c..970bbb9 100644
--- a/vdirsyncer/cli/discover.py
+++ b/vdirsyncer/cli/discover.py
@@ -81,6 +81,7 @@ async def collections_for_pair(
     b_discovered = _DiscoverResult(pair.config_b, connector=connector)
 
     if list_collections:
+        # TODO: We should gather data and THEN print, so it can be async.
         await _print_collections(
             pair.config_a["instance_name"],
             a_discovered.get_self,
@@ -275,27 +276,32 @@ async def _print_collections(
         )
         return
     logger.info(f"{instance_name}:")
+    tasks = []
     for args in discovered.values():
-        collection = args["collection"]
-        if collection is None:
-            continue
+        tasks.append(_print_single_collection(args, instance_name, connector))
 
-        args["instance_name"] = instance_name
-        try:
-            storage = await storage_instance_from_config(
-                args,
-                create=False,
-                connector=connector,
-            )
-            displayname = await storage.get_meta("displayname")
-        except Exception:
-            displayname = ""
+    await asyncio.gather(*tasks)
 
-        logger.info(
-            "  - {}{}".format(
-                json.dumps(collection),
-                f' ("{displayname}")'
-                if displayname and displayname != collection
-                else "",
-            )
+
+async def _print_single_collection(args, instance_name, connector):
+    collection = args["collection"]
+    if collection is None:
+        return
+
+    args["instance_name"] = instance_name
+    try:
+        storage = await storage_instance_from_config(
+            args,
+            create=False,
+            connector=connector,
         )
+        displayname = await storage.get_meta("displayname")
+    except Exception:
+        displayname = ""
+
+    logger.info(
+        "  - {}{}".format(
+            json.dumps(collection),
+            f' ("{displayname}")' if displayname and displayname != collection else "",
+        )
+    )