Data system refactor and core redesign for public.

Redesigned data and core systems to be public-capable.

bot/data/connection.py

@@ -0,0 +1,40 @@
+import logging
+
+import psycopg2 as psy
+
+from meta import log, conf
+from constants import DATA_VERSION
+from .cursor import DictLoggingCursor
+
+
+# Set up database connection
+log("Establishing connection.", "DB_INIT", level=logging.DEBUG)
+conn = psy.connect(conf.bot['database'], cursor_factory=DictLoggingCursor)
+
+# Replace char used by the connection for query formatting
+_replace_char: str = '%s'
+
+# conn.set_trace_callback(lambda message: log(message, context="DB_CONNECTOR", level=logging.DEBUG))
+# sq.register_adapter(datetime, lambda dt: dt.timestamp())
+
+
+# Check the version matches the required version
+with conn:
+    log("Checking db version.", "DB_INIT")
+    cursor = conn.cursor()
+
+    # Get last entry in version table, compare against desired version
+    cursor.execute("SELECT * FROM VersionHistory ORDER BY time DESC LIMIT 1")
+    current_version, _, _ = cursor.fetchone()
+
+    if current_version != DATA_VERSION:
+        # Complain
+        raise Exception(
+            ("Database version is {}, required version is {}. "
+             "Please migrate database.").format(current_version, DATA_VERSION)
+        )
+
+    cursor.close()
+
+
+log("Established connection.", "DB_INIT")