Initial project

internal/config/load.go

@@ -0,0 +1,96 @@
+/*
+Copyright © 2026 Craig Williams <craig@avsdev.uk>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+package config
+
+import (
+	"fmt"
+	"log/slog"
+
+	"github.com/joho/godotenv"
+	"github.com/spf13/viper"
+)
+
+// Reads in dotenv file for configuration
+func loadEnv() error {
+	if err := godotenv.Load(); err != nil {
+		return fmt.Errorf("invalid .env file: %w", err)
+	}
+	return nil
+}
+
+// Reads in config file and ENV variables if set to form a configuration.
+func loadConfig(cfgFile string) error {
+	if cfgFile != "" {
+		// Use config file from the flag.
+		viper.SetConfigFile(cfgFile)
+	} else {
+		// Search config in /etc or local directory.
+		viper.AddConfigPath(EtcConfigPath)
+		viper.AddConfigPath(".")
+
+		viper.SetConfigName("config")
+	}
+
+	// Load default configuration
+	LoadDefaultConfig()
+
+	viper.SetEnvPrefix(EnvPrefix)
+	viper.AutomaticEnv() // read in environment variables that match
+
+	err := viper.ReadInConfig()
+	if err != nil {
+		if _, ok := err.(viper.ConfigFileNotFoundError); ok {
+			// Indicates an explicitly set config file is not found or
+			// that no config file was found in any search path
+			slog.Warn("No config file found!")
+		} else {
+			// Config file was found but another error was produced
+			return err
+		}
+	} else {
+		// Config file found and successfully parsed
+		slog.Info("Using config file: " + viper.ConfigFileUsed())
+	}
+	return nil
+}
+
+// Initilises environment file configuration and general app configuration
+func Init(cfgFile string, conf *JobSearchConfig) error {
+	if err := loadEnv(); err != nil {
+		return err
+	}
+	if conf.Logging.LogLevel() <= slog.LevelDebug {
+		printEnv()
+	}
+
+	if err := loadConfig(cfgFile); err != nil {
+		return err
+	}
+
+	oldLogLevel := conf.Logging.Level
+	LoadFromViper(conf)
+	if ConfigLevelToLogLevel(oldLogLevel) < conf.Logging.LogLevel() {
+		conf.Logging.Level = oldLogLevel
+	}
+
+	if conf.Logging.LogLevel() <= slog.LevelDebug {
+		printLoadedConfig()
+		printConfig(*conf)
+	}
+
+	return nil
+}