Implement dynamic id_pattern changes from server

stechuhr_client/client.py

@@ -41,6 +41,15 @@ EVENT_FORMAT = "llHHI"
 EVENT_SIZE = struct.calcsize(EVENT_FORMAT)
 
 
+def string_to_list(s:str, delimiter: str="\n") -> List[str]:
+    """
+    Split a string to a list derived from a delimiter. If the string contains
+    no delimiter, still return a list containing the string
+    """
+    if delimiter in s:
+        return s.split(delimiter)
+    else:
+        return [s]
 
 
 def repeat(l, index):
@@ -320,16 +329,36 @@ def read_key_input(input_queue, config, logger):
         time.sleep(0.01)
 
 
-def update_id_patterns(config) -> 'Config':
+def update_id_patterns(config, logger) -> 'Config':
+    """
+    Update the id_patterns from the server via http
+    """
     if config["server"]["port"] == 80:
         protocol = "http"
     else:
         protocol = "https"
 
     url = '{}://{}/config/database/id_patterns'.format(protocol, config["server"]["address"].rstrip("/"))
-    r = requests.get(url)
-    print(r.text)
-    # config["client"]["id_patterns"]
+    logger.debug("Requesting id_pattern update at address: {}".format(url))
+
+    # Send request
+    r = requests.get(url, timeout=config["server"]["timeout"])
+
+    # If the response was ok update the pattern if it changed, else display a warning
+    if r.ok:
+        patterns = string_to_list(r.text)
+        if set(patterns) == set(config["client"]["id_patterns"]):
+            logger.debug("No change in serverside id_pattern, so didn't update")
+        else:
+            # Only compile the patterns once we know something changed
+            patterns = [re.compile(p) for p in patterns]
+            config["client"]["id_patterns"] = patterns
+            logger.info("Received a newly updated patterns list from the server")
+    else:
+        logger.warn("Server at \"{}\" responded with {}".format(url, r.status))
+
+    return config
+
 
 def main():
     logger = logging.getLogger(APPLICATION_NAME)
@@ -374,9 +403,10 @@ def main():
         else:
             time.sleep(0.01)
             
+        # Update the patterns at the pace defined by config["server"]["update_frequency"]
         if last_pattern_update is None or time.time() - last_pattern_update > config["server"]["update_frequency"]:
             last_pattern_update = time.time()
-            update_id_patterns(config)
+            config = update_id_patterns(config, logger)
 
 
         time.sleep(0.01)

stechuhr_client/config.py

@@ -26,7 +26,9 @@ address = "127.0.0.1"
 port = 80
 timeout = 5
 verify_cert = true
-update_frequency = 10
+
+# Frequency of requesting pattern updates from the server in seconds
+update_frequency = 600
 
 [client]
 location = "lerchenfeld/mensa"