Add DB initialization code. Fix DB schema

constants.py

@@ -7,3 +7,21 @@ DB_CONFIG_FILE_NAME = 'config.yaml'
 DEFAULT_DB_NAME = 'hanabi-league'
 DEFAULT_DB_USER = 'hanabi-league'
 DEFAULT_DB_PASS = 'hanabi-league'
+
+DB_TABLE_NAMES = [
+    "users"
+    , "user_accounts"
+    , "downloads"
+    , "variants"
+    , "games"
+    , "game_participants"
+    , "game_actions"
+    , "seeds"
+    , "variant_base_ratings"
+    , "variant_ratings"
+    , "user_base_ratings"
+    , "user_ratings"
+    , "statistics"
+]
+
+DATABASE_SCHEMA_PATH = 'install/database_schema.sql'

database.py

@@ -1,5 +1,7 @@
 import psycopg2
+import psycopg2.extensions
 
+import constants
 from config import read_db_config
 from log_setup import logger
 
@@ -16,7 +18,7 @@ class DBConnectionManager:
         ))
         logger.debug("Established database connection.")
 
-    def get_connection(self):
+    def get_connection(self) -> psycopg2.extensions.connection:
         """
         Get the database connection.
         If not already connected, this reads the database config file and connects to the DB.
@@ -28,4 +30,33 @@ class DBConnectionManager:
 
 
 # Global instance that will hold our DB connection
-conn_manager = DBConnectionManager()
+conn_manager = DBConnectionManager()
+
+
+def get_existing_tables():
+    conn = conn_manager.get_connection()
+    cur = conn.cursor()
+    table_names = ", ".join("'{}'".format(tablename) for tablename in constants.DB_TABLE_NAMES)
+    cur.execute(
+        "SELECT tablename FROM pg_tables WHERE"
+        "  schemaname = 'public' AND"
+        "  tablename IN ({})".format(
+            table_names
+        )
+    )
+    return [table for (table,) in cur.fetchall()]
+
+
+def init_database(erase: bool = False):
+    tables = get_existing_tables()
+
+    if not erase and len(tables) > 0:
+        logger.error("Aborting database initialization: Tables {} already exist".format(", ".join(tables)))
+        return
+    conn = conn_manager.get_connection()
+    cur = conn.cursor()
+
+    with open(constants.DATABASE_SCHEMA_PATH, "r") as f:
+        cur.execute(f.read())
+        conn.commit()
+    logger.verbose("Initialized DB tables.")

install/database_schema.sql

@@ -65,25 +65,25 @@
 *   To be honest, I'd also like to apply all of the code to some non-league related games where I'd need this :D.
 */
 
-DROP TABLE IF EXISTS users;
+DROP TABLE IF EXISTS users CASCADE;
 CREATE TABLE users (
   id SERIAL PRIMARY KEY,
-  name TEXT NOT NULL
-  discord_tag TEXT,
+  name TEXT NOT NULL,
+  discord_tag TEXT
 );
 
 
-DROP TABLE IF EXISTS user_accounts;
+DROP TABLE IF EXISTS user_accounts CASCADE;
 CREATE TABLE user_accounts (
   /* The username from hanab.live. This will be used a) for associating games to one of our user_ids and b) show up in the player profile. */
-  username TEXT NOT NULL,
+  username TEXT PRIMARY KEY,
   /**
   * Hanab.live stores a normalized username for each account to ensure that usernames are case-insensitive and don't have weird unicodes that resemble each other.
   * It uses go-unidecode to generate these from the actual usernames, and I suggest we do the same.
   * The corresponding python package is 'unidecode', so we should just use that here.
   * This will then ensure that no two sign-ups correspond to the same hanab.live account.
   */
-  normalized_username TEXT NOT NULL UNIQUE
+  normalized_username TEXT NOT NULL UNIQUE,
   user_id INTEGER NOT NULL,
   FOREIGN KEY (user_id) REFERENCES users (id) ON DELETE CASCADE
 );
@@ -99,19 +99,18 @@ CREATE TABLE user_accounts (
 DROP TABLE IF EXISTS downloads;
 CREATE TABLE downloads (
   /** Notice this has to be a hanab.live username, not a user_id */
-  username INTEGER NOT NULL,
-  latest_game_id INTEGER NOT NULL,
-  FOREIGN KEY (user_id) REFERENCES users (id)
+  username TEXT PRIMARY KEY REFERENCES user_accounts,
+  latest_game_id INTEGER NOT NULL
 );
 
 /**
 * For completeness, I suggest we store the hanab.live variants here together with their names.
 * So this will just be a static table that we populate once.
 */
-DROP TABLE IF EXISTS variants;
+DROP TABLE IF EXISTS variants CASCADE;
 CREATE TABLE variants (
   id INTEGER PRIMARY KEY,
-  name TEXT NOT NULL
+  name TEXT NOT NULL,
   num_suits INTEGER NOT NULL,
   clue_starved BOOLEAN NOT NULL,
   max_score SMALLINT NOT NULL
@@ -122,7 +121,7 @@ CREATE TABLE variants (
 * - Only download detailed data for each game once (The actions taken and the actual deck)
 * - We can evaluate statistics (also complicated ones) whenever we want, independent of the server
 */
-DROP TABLE IF EXISTS games;
+DROP TABLE IF EXISTS games CASCADE;
 CREATE TABLE games (
   /** Here, we should use the same ids as the game ids from hanab.live */
   id INTEGER PRIMARY KEY,
@@ -141,6 +140,7 @@ CREATE TABLE games (
   FOREIGN KEY (variant_id) REFERENCES variants (id)
 );
 
+DROP TABLE IF EXISTS game_participants CASCADE;
 CREATE TABLE game_participants (
   game_id INTEGER NOT NULL,
   /**
@@ -223,7 +223,7 @@ CREATE TABLE seeds (
   suit_index SMALLINT NOT NULL,
   rank SMALLINT NOT NULL,
   CONSTRAINT cards_unique UNIQUE (seed, card_index)
-)
+);
 
 
 /**
@@ -242,14 +242,16 @@ CREATE TABLE seeds (
 /**
 * Records the initial ratings of variants
 */
+DROP TABLE IF EXISTS variant_base_ratings CASCADE;
 CREATE TABLE variant_base_ratings (
   variant_id SMALLINT PRIMARY KEY,
-  rating REAL NOT NULL,
+  rating REAL NOT NULL
 );
 
 /**
 * Store a separate row for each elo update to one of the variants
 */
+DROP TABLE IF EXISTS variant_ratings CASCADE;
 CREATE TABLE variant_ratings (
   /** This should reference the game that triggered the elo update */
   league_id INTEGER PRIMARY KEY REFERENCES games,
@@ -258,9 +260,10 @@ CREATE TABLE variant_ratings (
   change REAL NOT NULL,
   value_after REAL NOT NULL,
 
-  FOREIGN KEY (variant_id) REFERENCES variants (id),
+  FOREIGN KEY (variant_id) REFERENCES variants (id)
 );
 
+DROP TABLE IF EXISTS user_base_ratings CASCADE;
 CREATE TABLE user_base_ratings (
   user_id SMALLINT,
   /**
@@ -276,6 +279,7 @@ CREATE TABLE user_base_ratings (
   FOREIGN KEY (user_id) REFERENCES users (id)
 );
 
+DROP TABLE IF EXISTS user_ratings CASCADE;
 CREATE TABLE user_ratings (
   /** This should reference the game that triggered the elo update. I would use the league_id here for proper ordering. */
   league_id INTEGER PRIMARY KEY REFERENCES games,
@@ -298,6 +302,7 @@ CREATE TABLE user_ratings (
 /* TABLES RELATED TO STATISTICS */
 
 /** This is a rough outline, not really happy with it right now. */
+DROP TABLE IF EXISTS statistics CASCADE;
 CREATE TABLE statistics (
   game_id INTEGER PRIMARY KEY,
   /** I'd say all of the following can just be null in case we have not evaluated them yet. */