feat: initial project setup

backend/app/config.py

@@ -0,0 +1,41 @@
+"""Application configuration from environment variables."""
+
+import os
+
+
+class Settings:
+    """Application settings loaded from environment variables.
+
+    Configure via DATABASE_URL (single connection string) or individual
+    POSTGRES_* variables. The application expects the target database to
+    contain:
+      - A listings table (default: marts.funda_listings)
+      - An ELO schema with ratings, comparisons, and sample_listings tables
+        (default: elo.*)
+    """
+
+    POSTGRES_HOST: str = os.getenv("POSTGRES_HOST", "localhost")
+    POSTGRES_PORT: int = int(os.getenv("POSTGRES_PORT", "5432"))
+    POSTGRES_USER: str = os.getenv("POSTGRES_USER", "postgres")
+    POSTGRES_PASSWORD: str = os.getenv("POSTGRES_PASSWORD", "postgres")
+    POSTGRES_DB: str = os.getenv("POSTGRES_DB", "postgres")
+
+    LISTINGS_SCHEMA: str = os.getenv("LISTINGS_SCHEMA", "marts")
+    LISTINGS_TABLE: str = os.getenv("LISTINGS_TABLE", "funda_listings")
+    ELO_SCHEMA: str = os.getenv("ELO_SCHEMA", "elo")
+
+    K_FACTOR: float = float(os.getenv("ELO_K_FACTOR", "32"))
+    DEFAULT_ELO: float = float(os.getenv("ELO_DEFAULT_RATING", "1500"))
+
+    @property
+    def database_url(self) -> str:
+        url = os.getenv("DATABASE_URL")
+        if url:
+            return url
+        return (
+            f"postgresql+psycopg2://{self.POSTGRES_USER}:{self.POSTGRES_PASSWORD}"
+            f"@{self.POSTGRES_HOST}:{self.POSTGRES_PORT}/{self.POSTGRES_DB}"
+        )
+
+
+settings = Settings()