Create Episode 05 - TTLcache with cachetools.py

Author: Pythobit

Season 15 - Interacting with APIs with Python/Episode 05 - TTLcache with cachetools.py

@@ -0,0 +1,25 @@
+# openexchange.py
+import requests
+from cachetools import cached, TTLCache
+
+
+class OpenExchangeClient:
+    BASE_URL = 'https://openexchangerates.org/api'
+
+    def __init__(self, app_id):
+        self.app_id = app_id
+
+    @property
+    @cached(cache=TTLCache(maxsize=2, ttl=900))   # updates TTL - time to live cache
+    def latest(self):
+        return requests.get(f'{self.BASE_URL}/latest.json?app_id={self.app_id}').json()
+
+    def convert(self, from_amount, from_currency, to_currency):
+        rates = self.latest['rates']
+        to_rate = rates[to_currency]
+
+        if from_currency == 'USD':
+            return from_amount * to_rate
+        else:
+            from_in_usd = from_amount / rates[from_currency]
+            return from_in_usd * to_rate