adds sqlite option, sanitizes inputs

app.py

@@ -10,7 +10,7 @@
 @app.route(f'/{endpoint}', methods=["POST"])
 def run():
     try:
-        sb.SpotBot(request, tables.HamAlertTable(), discord_http.DiscordHttp()).process()
+        sb.SpotBot(request, tables.create_table_client(), discord_http.DiscordHttp()).process()
     except Exception as _excpt:
         logging.error(f"Exception occurred: {_excpt}")
         return make_response(f"Exception occurred: {_excpt}", 500)

tables.py

@@ -1,25 +1,28 @@
 import logging
 import os
+import sqlite3
 from azure.data.tables import TableServiceClient
 from azure.data.tables import UpdateMode
 
-class HamAlertTable:
-    def __init__(self):
-        connection_string = os.getenv('AzureWebJobsStorage')
-        table_name = os.getenv('TABLE_NAME')
-        table_service_client = TableServiceClient.from_connection_string(conn_str=connection_string)
-        self.table_client = table_service_client.get_table_client(table_name=table_name)
+class BaseAlertTable:
+    def query_for_entity(self, callsign):
+        raise NotImplementedError
+
+    def upsert_entity(self, callsign, messageId):
+        raise NotImplementedError
 
-    def initialize_table(self):
+class HamAlertAzureTable(BaseAlertTable):
+    def __init__(self):
         connection_string = os.getenv('AzureWebJobsStorage')
         table_name = os.getenv('TABLE_NAME')
         table_service_client = TableServiceClient.from_connection_string(conn_str=connection_string)
         self.table_client = table_service_client.get_table_client(table_name=table_name)
 
     def query_for_entity(self, callsign):
-        entities = [ent for ent in self.table_client.query_entities(f"PartitionKey eq '{callsign}' and RowKey eq '{callsign}'")]
+        safe_callsign = callsign.replace("'", "''")
+        entities = [ent for ent in self.table_client.query_entities(f"PartitionKey eq '{safe_callsign}' and RowKey eq '{safe_callsign}'")]
         if len(entities) > 0:
-            logging.info(f"Entity already exists for {callsign}")
+            logging.info(f"Entity already exists for {safe_callsign}")
         return entities[0] if len(entities) > 0 else None
 
     def upsert_entity(self, callsign, messageId):
@@ -28,4 +31,41 @@ def upsert_entity(self, callsign, messageId):
             u'RowKey': callsign,
             u'MessageId': messageId
         }
-        self.table_client.upsert_entity(mode=UpdateMode.REPLACE, entity=entity)
+        self.table_client.upsert_entity(mode=UpdateMode.REPLACE, entity=entity)
+
+class HamAlertSqliteTable(BaseAlertTable):
+    def __init__(self):
+        db_path = os.getenv('SQLITE_DB_PATH', 'ham_alerts.db')
+        self.conn = sqlite3.connect(db_path)
+        self._create_table()
+
+    def _create_table(self):
+        cursor = self.conn.cursor()
+        cursor.execute('''
+            CREATE TABLE IF NOT EXISTS ham_alerts (
+                callsign TEXT PRIMARY KEY,
+                message_id TEXT
+            )
+        ''')
+        self.conn.commit()
+
+    def query_for_entity(self, callsign):
+        cursor = self.conn.cursor()
+        cursor.execute('SELECT callsign, message_id FROM ham_alerts WHERE callsign = ?', (callsign,))
+        result = cursor.fetchone()
+        if result:
+            logging.info(f"Entity already exists for {callsign}")
+            return {'PartitionKey': result[0], 'RowKey': result[0], 'MessageId': result[1]}
+        return None
+
+    def upsert_entity(self, callsign, messageId):
+        cursor = self.conn.cursor()
+        cursor.execute('INSERT OR REPLACE INTO ham_alerts (callsign, message_id) VALUES (?, ?)',
+                      (callsign, messageId))
+        self.conn.commit()
+
+def create_table_client():
+    storage_type = os.getenv('STORAGE_TYPE', 'sqlite').lower()
+    if storage_type == 'azure':
+        return HamAlertAzureTable()
+    return HamAlertSqliteTable()