Clear cached currencies on update and after APP_KEY is set

src/config.py

@@ -42,6 +42,7 @@
 CRYPTO_COMPARE_BASE_URL = 'https://min-api.cryptocompare.com/data/price?fsym={}&tsyms={}'
 SYMBOLS_PER_REQUEST = 20
 USER_AGENT = 'Alfred Convert/{}'.format(os.getenv('alfred_workflow_version'))
+NOKEY_FILENAME = 'nokey'
 
 # ----------------------------------------------------------------------
 # Unit definition files

src/convert.py

@@ -19,6 +19,7 @@
 
 from workflow import Workflow3, ICON_WARNING, ICON_INFO
 from workflow.background import run_in_background, is_running
+from workflow.update import Version
 from config import (
     bootstrap,
     DEFAULT_UNIT_DEFINITIONS,
@@ -32,6 +33,8 @@
     DEFAULT_SETTINGS,
     HELP_URL,
     ICON_UPDATE,
+    NOKEY_FILENAME,
+    OPENX_APP_KEY,
     THOUSANDS_SEPARATOR,
     UPDATE_SETTINGS,
 )
@@ -44,6 +47,38 @@
 # Q = ureg.Quantity
 
 
+def handle_update(wf):
+    """Clear cache on update.
+
+    Delete cached data if last-run version used a different format,
+    or if user has just added the ``APP_KEY`` for fiat currency
+    exchange rates.
+
+    """
+    nokey = wf.cachefile(NOKEY_FILENAME)
+    clear = False
+
+    # Clear cache if previous version was old
+    lv = wf.last_version_run
+    log.debug('version=%s, last_version=%s', wf.version, lv)
+    if wf.version > Version('3.0') and lv < Version('3.1'):
+        log.debug('clearing cache: saved data is incompatible')
+        clear = True
+
+    if OPENX_APP_KEY:
+        if os.path.exists(nokey):
+            os.unlink(nokey)
+            log.debug('clearing cache: APP_KEY was set')
+            clear = True
+    else:
+        if not os.path.exists(nokey):
+            open(nokey, 'wb').write('')
+
+    if clear:
+        wf.cache_data(CURRENCY_CACHE_NAME, None)
+        log.debug('cleared old cached currencies')
+
+
 class NoToUnits(Exception):
     """Raised if there are no to units (or defaults)."""
 
@@ -390,6 +425,7 @@ def main(wf):
     query = wf.args[0]  # .lower()
     log.debug('query : %s', query)
 
+    handle_update(wf)
     # Create data files if necessary
     bootstrap(wf)
 

src/currency.py

@@ -110,7 +110,7 @@ def load_openx_rates(symbols):
     wanted = set(symbols)
     if not OPENX_APP_KEY:
         log.warning(
-            'Not fetching fiat currency exchange rates: '
+            'not fetching fiat currency exchange rates: '
             'APP_KEY for openexchangerates.org not set. '
             'Please sign up for a free account here: '
             'https://openexchangerates.org/signup/free'
@@ -147,7 +147,7 @@ def load_active_currencies():
     with open(user_currencies) as fp:
         for line in fp:
             line = line.strip()
-            if line.startswith('#'):
+            if not line or line.startswith('#'):
                 continue
 
             symbols.add(line.upper())
@@ -201,7 +201,8 @@ def main(wf):
     start_time = time.time()
     bootstrap(wf)
 
-    log.info('fetching exchange rates from Yahoo! and CryptoCompare.com ...')
+    log.info('fetching exchange rates from OpenExchangeRates.org and '
+             'CryptoCompare.com ...')
 
     rates = wf.cached_data(CURRENCY_CACHE_NAME,
                            fetch_exchange_rates,

src/info.plist

@@ -637,7 +637,7 @@ UPDATE_INTERVAL is the number of minutes between exchange rate updates.</string>
 		<string>APP_KEY</string>
 	</array>
 	<key>version</key>
-	<string>3.2</string>
+	<string>3.2.1</string>
 	<key>webaddress</key>
 	<string></string>
 </dict>