Initial commit

migrations/runner.py

@@ -0,0 +1,106 @@
+"""
+Database Migration Runner
+
+Reads SQL migration files from the migrations/ directory, checks which
+have already been applied via the schema_migrations table, and runs
+any unapplied migrations in order.
+
+Usage:
+    python migrations/runner.py
+"""
+
+import os
+import re
+import sys
+import psycopg2
+from dotenv import load_dotenv
+
+
+def get_migration_files(migrations_dir):
+    """Find all SQL migration files and return sorted by version number."""
+    pattern = re.compile(r"^(\d+)_.+\.sql$")
+    files = []
+    for filename in os.listdir(migrations_dir):
+        match = pattern.match(filename)
+        if match:
+            version = int(match.group(1))
+            files.append((version, filename))
+    return sorted(files, key=lambda x: x[0])
+
+
+def ensure_migrations_table(conn):
+    """Create schema_migrations table if it doesn't exist."""
+    with conn.cursor() as cur:
+        cur.execute("""
+            CREATE TABLE IF NOT EXISTS schema_migrations (
+                version INTEGER PRIMARY KEY,
+                applied_at TIMESTAMP DEFAULT NOW()
+            )
+        """)
+        conn.commit()
+
+
+def get_applied_versions(conn):
+    """Get set of already-applied migration versions."""
+    with conn.cursor() as cur:
+        cur.execute("SELECT version FROM schema_migrations ORDER BY version")
+        return {row[0] for row in cur.fetchall()}
+
+
+def run_migration(conn, version, filepath):
+    """Run a single migration file inside a transaction."""
+    print(f"  Applying migration {version}: {os.path.basename(filepath)}...")
+    with open(filepath, "r", encoding="utf-8") as f:
+        sql = f.read()
+
+    with conn.cursor() as cur:
+        cur.execute(sql)
+        cur.execute(
+            "INSERT INTO schema_migrations (version) VALUES (%s)",
+            (version,),
+        )
+        conn.commit()
+    print(f"  ✓ Migration {version} applied successfully")
+
+
+def main():
+    load_dotenv()
+    database_url = os.environ.get("DATABASE_URL")
+    if not database_url:
+        print("ERROR: DATABASE_URL not set in .env")
+        sys.exit(1)
+
+    # Determine migrations directory
+    migrations_dir = os.path.dirname(os.path.abspath(__file__))
+
+    print(f"Connecting to database...")
+    conn = psycopg2.connect(database_url)
+
+    try:
+        ensure_migrations_table(conn)
+        applied = get_applied_versions(conn)
+        migrations = get_migration_files(migrations_dir)
+
+        pending = [(v, f) for v, f in migrations if v not in applied]
+
+        if not pending:
+            print("All migrations are up to date.")
+            return
+
+        print(f"Found {len(pending)} pending migration(s):")
+        for version, filename in pending:
+            filepath = os.path.join(migrations_dir, filename)
+            run_migration(conn, version, filepath)
+
+        print("\nAll migrations applied successfully!")
+
+    except Exception as e:
+        conn.rollback()
+        print(f"\nERROR: Migration failed: {e}")
+        sys.exit(1)
+    finally:
+        conn.close()
+
+
+if __name__ == "__main__":
+    main()