[card-client] make Card.get_data more efficient (#1750)

* [card-client] make `Card.get_data` more efficient

* [card-updates] hold a time.time value in data updates
- Helps ensure that stale updates from a server can be ignored

* [card-ui] remove unecessary console logs

Author: valayDave

metaflow/plugins/cards/card_cli.py

@@ -10,6 +10,7 @@
 import re
 from metaflow._vendor import click
 import os
+import time
 import json
 import uuid
 import signal
@@ -454,7 +455,11 @@ def _add_token_html(html):
     def _add_token_json(json_msg):
         if json_msg is None:
             return None
-        return {"reload_token": _reload_token(), "data": json_msg}
+        return {
+            "reload_token": _reload_token(),
+            "data": json_msg,
+            "created_on": time.time(),
+        }
 
     def _safe_call_function(func, *args, **kwargs):
         """

metaflow/plugins/cards/card_client.py

@@ -47,6 +47,7 @@ def __init__(
         self._created_on = created_on
         self._card_ds = card_ds
         self._card_id = id
+        self._data_path = None
 
         # public attributes
         self.hash = hash
@@ -59,12 +60,14 @@ def __init__(
 
     def get_data(self) -> Optional[dict]:
         # currently an internal method to retrieve a card's data.
-        data_paths = self._card_ds.extract_data_paths(
-            card_type=self.type, card_hash=self.hash, card_id=self._card_id
-        )
-        if len(data_paths) == 0:
-            return None
-        return self._card_ds.get_card_data(data_paths[0])
+        if self._data_path is None:
+            data_paths = self._card_ds.extract_data_paths(
+                card_type=self.type, card_hash=self.hash, card_id=self._card_id
+            )
+            if len(data_paths) == 0:
+                return None
+            self._data_path = data_paths[0]
+        return self._card_ds.get_card_data(self._data_path)
 
     def get(self) -> str:
         """

metaflow/plugins/cards/card_modules/main.js

@@ -14,8 +14,6 @@ export const cardData: Writable<types.CardResponse | undefined> =
 (window as any).metaflow_card_update = (
   dataChanges: Record<string, types.CardComponent>
 ) => {
-  console.log("metaflow_card_update", dataChanges, cardData?.update);
-
   cardData?.update((d: any) => {
     const newData: types.CardResponse = { ...d };