def load_config_from()

in otava/config.py [0:0]

• 72 lines of code
• 16 McCabe index (conditional complexity)

def load_config_from(config_file: Path) -> Config:
    """Loads config from the specified location"""
    try:
        content = expandvars(config_file.read_text(), nounset=True)
        yaml = YAML(typ="safe")
        config = yaml.load(content)
        """
        if Grafana configs not explicitly set in yaml file, default to same as Graphite
        server at port 3000
        """
        graphite_config = None
        grafana_config = None
        if "graphite" in config:
            if "url" not in config["graphite"]:
                raise ValueError("graphite.url")
            graphite_config = GraphiteConfig(url=config["graphite"]["url"])
            if config.get("grafana") is None:
                config["grafana"] = {}
                config["grafana"]["url"] = f"{config['graphite']['url'].strip('/')}:3000/"
                config["grafana"]["user"] = os.environ.get("GRAFANA_USER", "admin")
                config["grafana"]["password"] = os.environ.get("GRAFANA_PASSWORD", "admin")
            grafana_config = GrafanaConfig(
                url=config["grafana"]["url"],
                user=config["grafana"]["user"],
                password=config["grafana"]["password"],
            )

        slack_config = None
        if config.get("slack") is not None:
            if not config["slack"]["token"]:
                raise ValueError("slack.token")
            slack_config = SlackConfig(
                bot_token=config["slack"]["token"],
            )

        postgres_config = None
        if config.get("postgres") is not None:
            if not config["postgres"]["hostname"]:
                raise ValueError("postgres.hostname")
            if not config["postgres"]["port"]:
                raise ValueError("postgres.port")
            if not config["postgres"]["username"]:
                raise ValueError("postgres.username")
            if not config["postgres"]["password"]:
                raise ValueError("postgres.password")
            if not config["postgres"]["database"]:
                raise ValueError("postgres.database")

            postgres_config = PostgresConfig(
                hostname=config["postgres"]["hostname"],
                port=config["postgres"]["port"],
                username=config["postgres"]["username"],
                password=config["postgres"]["password"],
                database=config["postgres"]["database"],
            )

        bigquery_config = None
        if config.get("bigquery") is not None:
            bigquery_config = BigQueryConfig(
                project_id=config["bigquery"]["project_id"],
                dataset=config["bigquery"]["dataset"],
                credentials=config["bigquery"]["credentials"],
            )

        templates = load_templates(config)
        tests = load_tests(config, templates)
        groups = load_test_groups(config, tests)

        return Config(
            graphite=graphite_config,
            grafana=grafana_config,
            slack=slack_config,
            postgres=postgres_config,
            bigquery=bigquery_config,
            tests=tests,
            test_groups=groups,
        )

    except FileNotFoundError as e:
        raise ConfigError(f"Configuration file not found: {e.filename}")
    except KeyError as e:
        raise ConfigError(f"Configuration key not found: {e.args[0]}")
    except ValueError as e:
        raise ConfigError(f"Value for configuration key not found: {e.args[0]}")