From e757e1f2779d0f6c04451b6ab3c1d825165ae6e9 Mon Sep 17 00:00:00 2001
From: Tyler Goodlet <jgbt@protonmail.com>
Date: Mon, 4 Jul 2022 22:52:25 -0400
Subject: [PATCH] Use `match:` syntax in data feed subs processing

---
 piker/brokers/kraken/feed.py | 95 ++++++++++++++++++++++++------------
 1 file changed, 63 insertions(+), 32 deletions(-)

diff --git a/piker/brokers/kraken/feed.py b/piker/brokers/kraken/feed.py
index 71b75082..2d6ecbf1 100644
--- a/piker/brokers/kraken/feed.py
+++ b/piker/brokers/kraken/feed.py
@@ -117,9 +117,8 @@ async def stream_messages(
                 too_slow_count = 0
                 continue
 
-        if isinstance(msg, dict):
-            if msg.get('event') == 'heartbeat':
-
+        match msg:
+            case {'event': 'heartbeat'}:
                 now = time.time()
                 delay = now - last_hb
                 last_hb = now
@@ -130,11 +129,20 @@ async def stream_messages(
 
                 continue
 
-            err = msg.get('errorMessage')
-            if err:
-                raise BrokerError(err)
-        else:
-            yield msg
+            case {
+                'connectionID': _,
+                'event': 'systemStatus',
+                'status': 'online',
+                'version': _,
+            } as msg:
+                log.info(
+                    'WS connection is up:\n'
+                    f'{msg}'
+                )
+                continue
+
+            case _:
+                yield msg
 
 
 async def process_data_feed_msgs(
@@ -145,37 +153,60 @@ async def process_data_feed_msgs(
 
     '''
     async for msg in stream_messages(ws):
+        match msg:
+            case {
+                'errorMessage': errmsg
+            }:
+                raise BrokerError(errmsg)
 
-        chan_id, *payload_array, chan_name, pair = msg
+            case {
+                'event': 'subscriptionStatus',
+            } as sub:
+                log.info(
+                    'WS subscription is active:\n'
+                    f'{sub}'
+                )
+                continue
 
-        if 'ohlc' in chan_name:
+            case [
+                chan_id,
+                *payload_array,
+                chan_name,
+                pair
+            ]:
+                if 'ohlc' in chan_name:
+                    yield 'ohlc', OHLC(
+                        chan_id,
+                        chan_name,
+                        pair,
+                        *payload_array[0]
+                    )
 
-            yield 'ohlc', OHLC(chan_id, chan_name, pair, *payload_array[0])
+                elif 'spread' in chan_name:
 
-        elif 'spread' in chan_name:
+                    bid, ask, ts, bsize, asize = map(
+                        float, payload_array[0])
 
-            bid, ask, ts, bsize, asize = map(float, payload_array[0])
+                    # TODO: really makes you think IB has a horrible API...
+                    quote = {
+                        'symbol': pair.replace('/', ''),
+                        'ticks': [
+                            {'type': 'bid', 'price': bid, 'size': bsize},
+                            {'type': 'bsize', 'price': bid, 'size': bsize},
 
-            # TODO: really makes you think IB has a horrible API...
-            quote = {
-                'symbol': pair.replace('/', ''),
-                'ticks': [
-                    {'type': 'bid', 'price': bid, 'size': bsize},
-                    {'type': 'bsize', 'price': bid, 'size': bsize},
+                            {'type': 'ask', 'price': ask, 'size': asize},
+                            {'type': 'asize', 'price': ask, 'size': asize},
+                        ],
+                    }
+                    yield 'l1', quote
 
-                    {'type': 'ask', 'price': ask, 'size': asize},
-                    {'type': 'asize', 'price': ask, 'size': asize},
-                ],
-            }
-            yield 'l1', quote
+                # elif 'book' in msg[-2]:
+                #     chan_id, *payload_array, chan_name, pair = msg
+                #     print(msg)
 
-        # elif 'book' in msg[-2]:
-        #     chan_id, *payload_array, chan_name, pair = msg
-        #     print(msg)
-
-        else:
-            print(f'UNHANDLED MSG: {msg}')
-            yield msg
+            case _:
+                print(f'UNHANDLED MSG: {msg}')
+                # yield msg
 
 
 def normalize(
@@ -385,7 +416,7 @@ async def stream_quotes(
             msg_gen = process_data_feed_msgs(ws)
 
             # TODO: use ``anext()`` when it lands in 3.10!
-            typ, ohlc_last = await msg_gen.__anext__()
+            typ, ohlc_last = await anext(msg_gen)
 
             topic, quote = normalize(ohlc_last)