begin refactoring into namedtuple style, add period setup, transition to more modular and safer database state management

contest/db.py

@@ -1,8 +1,9 @@
 import logging
 import os
 import sqlite3
+from collections import namedtuple
 from datetime import datetime
-from typing import Optional
+from typing import Optional, List
 
 import aiosqlite
 
@@ -11,6 +12,10 @@ from contest import constants
 logger = logging.getLogger(__file__)
 logger.setLevel(constants.LOGGING_LEVEL)
 
+Guild = namedtuple('Guild', ['id', 'prefix', 'submission', 'period'])
+Submission = namedtuple('Submission', ['id', 'user', 'guild', 'timestamp'])
+Period = namedtuple('Period', ['id', 'guild', 'current_state', 'started_at', 'voting_at', 'finished_at', ''])
+
 
 class ContestDatabase(object):
     """
@@ -21,17 +26,24 @@ class ContestDatabase(object):
         self.conn = conn
 
     @classmethod
-    async def create(cls) -> 'ContestDatabase':
+    async def create(cls, dest: str = constants.DATABASE) -> 'ContestDatabase':
         """
         Constructs a ContestDatabase object connecting to the default database location with the proper connection settings.
         :return: A fully realized ContestDatabase object.
         """
-        conn = await aiosqlite.connect(constants.DATABASE, detect_types=sqlite3.PARSE_DECLTYPES)
+
-        logger.info(f'Asynchronous SQLite3 connection made to ./{os.path.relpath(constants.DATABASE)}')
+        conn = await aiosqlite.connect(dest, detect_types=sqlite3.PARSE_DECLTYPES)
+        if dest.startswith(':memory:'):
+            logger.info('Asynchronous SQLite3 connection started in memory.')
+        else:
+            logger.info(f'Asynchronous SQLite3 connection made to ./{os.path.relpath(constants.DATABASE)}')
+
         db = ContestDatabase(conn)
         await db.setup()
         await conn.commit()
-        logger.info('ContestDatabase instance created.')
+
+        logger.info('ContestDatabase instance created, database setup.')
+
         return db
 
     async def setup(self) -> None:
@@ -43,7 +55,8 @@ class ContestDatabase(object):
                 await self.conn.execute('''CREATE TABLE IF NOT EXISTS guild
                                             (id INTEGER PRIMARY KEY,
                                             prefix TEXT DEFAULT '$',
-                                            submission INTEGER NULLABLE)''')
+                                            submission INTEGER NULLABLE,
+                                            period INTEGER)''')
                 logger.info(f"'guild' table created.")
 
             await cur.execute('''SELECT name FROM sqlite_master WHERE type='table' AND name = ?;''', ['submission'])
@@ -54,6 +67,18 @@ class ContestDatabase(object):
                                             guild INTEGER,
                                             timestamp DATETIME)''')
                 logger.info(f"'submission' table created.")
+
+            await cur.execute('''SELECT name FROM sqlite_master WHERE type='table' AND name = ?;''', ['period'])
+            if await cur.fetchone() is None:
+                await self.conn.execute('''CREATE TABLE IF NOT EXISTS period
+                                            (id INTEGER PRIMARY KEY,
+                                            guild INTEGER,
+                                            current_state INTEGER,
+                                            started_at TIMESTAMP,
+                                            voting_at TIMESTAMP DEFAULT NULL,
+                                            finished_at TIMESTAMP DEFAULT NULL)''')
+                logger.info(f"'period' table created.")
+
         finally:
             await cur.close()
 
@@ -67,31 +92,46 @@ class ContestDatabase(object):
         await self.conn.execute('''UPDATE guild SET prefix = ? WHERE id = ?''', [new_prefix, guild_id])
         await self.conn.commit()
 
-    async def is_setup(self, guild_id: int) -> bool:
+    async def get_submission(self, guild_id: int, user_id: int) -> Optional[Submission]:
-        """Checks whether the bot is setup to complete submission channel related commands."""
+        """Retrieves a row from the submission table by the associated unique Guild ID and User ID"""
         cur = await self.conn.cursor()
         try:
-            await cur.execute('''SELECT submission FROM guild WHERE id = ?''', [guild_id])
+            await cur.execute('''SELECT * FROM submission WHERE guild = ? AND user = ?''', [guild_id, user_id])
-            t = await cur.fetchone()
+            row = await cur.fetchone()
-            print(t)
+            return None if row is None else Submission._make(row)
-            return t['submission']
         finally:
             await cur.close()
 
-    async def get_prefix(self, guild_id: int) -> str:
+    async def get_guild(self, guild_id: int) -> Optional[Guild]:
-        """Gets the prefix from a specific guild in the database."""
+        """Retrieves a row from the Guild table by the Guild ID"""
         cur = await self.conn.cursor()
         try:
-            await cur.execute('''SELECT prefix FROM guild WHERE id = ?''', [guild_id])
+            await cur.execute('''SELECT * FROM guild WHERE id = ?''', [guild_id])
-            return (await cur.fetchone())[0]
+            row = await cur.fetchone()
+            return None if row is None else Guild._make(row)
         finally:
             await cur.close()
 
-    async def get_submission_channel(self, guild_id: int) -> int:
+    async def get_period(self, period_id) -> Optional[Period]:
         cur = await self.conn.cursor()
         try:
-            await cur.execute('''SELECT submission FROM guild WHERE id = ?''', [guild_id])
+            await cur.execute('''SELECT * FROM period WHERE id = ?''', [period_id])
-            return (await cur.fetchone())[0]
+            row = await cur.fetchone()
+            return None if row is None else Period._make(row)
+        finally:
+            await cur.close()
+
+    async def get_current_period(self, guild_id: int) -> Optional[Period]:
+        """Retrieves a row from the Guild table by the Guild ID"""
+        cur = await self.conn.cursor()
+        try:
+            guild = await self.get_guild(guild_id)
+            if guild is None:
+                logger.debug(f'Guild {guild_id} does not exist.')
+                return None
+
+            if guild.period is not None:
+                return await self.get_period(guild.period)
         finally:
             await cur.close()
 
@@ -105,20 +145,41 @@ class ContestDatabase(object):
         await self.conn.execute('''DELETE FROM guild WHERE id = ?''', [guild_id])
         await self.conn.commit()
 
-    async def get_submission(self, guild_id: int, user_id: int) -> Optional[int]:
-        cur = await self.conn.cursor()
-        try:
-            await cur.execute('''SELECT id FROM submission WHERE guild = ? AND user = ?''', [guild_id, user_id])
-            row = await cur.fetchone()
-            if row is None:
-                return None
-            return row[0]
-        finally:
-            await cur.close()
-
     async def add_submission(self, submission_id: int, guild_id: int, user_id: int, timestamp: int = None) -> None:
         await self.conn.execute(
             '''INSERT INTO submission (id, user, guild, timestamp) VALUES (?, ?, ?, ?)''',
             [submission_id, user_id, guild_id, timestamp or datetime.utcnow().timestamp()]
         )
         await self.conn.commit()
+
+    @staticmethod
+    async def generate_insert_query(table: str, columns: List[str]) -> str:
+        return f'''INSERT INTO {table} ({", ".join(columns)}) VALUES ({", ".join("?" for _ in columns)})'''
+
+    async def new_period(self, period: Period) -> None:
+        """Given a period, adds the period to the table and updates the associated guild."""
+        cur = await self.conn.cursor()
+        try:
+            # Ensure the associated guild exists
+            if period.guild is None:
+                return logger.error(f'Period {period} did not include a guild to associate with.')
+
+            guild = await self.get_guild(period.guild)
+            if guild is None:
+                return logger.error(f'Specified guild {period.guild} does not exist.')
+
+            # Add the period to the table
+            items = filter(lambda item: item[1] is not None, period._asdict().items())
+            columns, values = zip(*items)
+            query = await self.generate_insert_query('period', list(columns))
+            logger.debug(f'Generated Insert Query: {query}')
+            await cur.execute(query, values)
+            await self.conn.commit()
+
+            # Update the associated guild's period
+            await cur.execute('''UPDATE guild SET period = ? WHERE id = ?''', [cur.lastrowid, period.guild])
+            await self.conn.commit()
+        finally:
+            await cur.close()
+
+    async def update_period(self, ):