From c2ed1295b71d7f661170debea700d83ff94c3f89 Mon Sep 17 00:00:00 2001
From: hokamsingh <hokamsingh.mongoosetech@gmail.com>
Date: Sat, 31 Aug 2024 13:37:09 +0530
Subject: [PATCH] feat: updated config module with typed getters and filter by
 prefix

---
 internal/core/config/config.go | 112 ++++++++++++++++++++++++---------
 1 file changed, 84 insertions(+), 28 deletions(-)

diff --git a/internal/core/config/config.go b/internal/core/config/config.go
index a542502..7f9a62b 100644
--- a/internal/core/config/config.go
+++ b/internal/core/config/config.go
@@ -1,25 +1,9 @@
-/*
-Package config provides functionality to load and manage application configuration
-from environment variables and .env files.
-
-The package leverages the `godotenv` package to load environment variables from a `.env` file into
-the application, allowing easy configuration management.
-
-Usage:
-
-	import "your/package/path/config"
-
-	func main() {
-		cfg := config.LoadConfig()
-		port := cfg.Get("PORT", "8080")
-		// Use the `port` variable...
-	}
-*/
 package config
 
 import (
 	"log"
 	"os"
+	"strconv"
 	"strings"
 
 	"github.com/joho/godotenv"
@@ -31,10 +15,6 @@ type Config map[string]string
 // LoadConfig loads environment variables into a Config map. It first attempts to load a `.env` file
 // using the `godotenv` package. If no `.env` file is found, it logs a message but continues to load
 // environment variables from the system.
-// Example:
-//
-//	cfg := config.LoadConfig()
-//	fmt.Println(cfg["PORT"])
 func LoadConfig() Config {
 	if err := godotenv.Load(); err != nil {
 		log.Printf("No .env file found: %v", err)
@@ -52,17 +32,93 @@ func LoadConfig() Config {
 	return config
 }
 
-// Get retrieves a value from the Config map based on the provided key. If the key does not exist
+// Get retrieves a string value from the Config map based on the provided key. If the key does not exist
 // in the Config, the function returns the specified default value.
-//
-// Example:
-//
-//	cfg := config.LoadConfig()
-//	port := cfg.Get("PORT", "8080")
-//	fmt.Println("Server will run on port:", port)
 func (c Config) Get(key, defaultValue string) string {
 	if value, exists := c[key]; exists {
 		return value
 	}
 	return defaultValue
 }
+
+// GetInt retrieves an integer value from the Config map based on the provided key. If the key does not exist
+// or cannot be converted to an integer, the function returns the specified default value.
+func (c Config) GetInt(key string, defaultValue int) int {
+	if value, exists := c[key]; exists {
+		if intValue, err := strconv.Atoi(value); err == nil {
+			return intValue
+		}
+		log.Printf("Invalid integer for key %s: %v", key, value)
+	}
+	return defaultValue
+}
+
+// GetBool retrieves a boolean value from the Config map based on the provided key. If the key does not exist
+// or cannot be converted to a boolean, the function returns the specified default value.
+func (c Config) GetBool(key string, defaultValue bool) bool {
+	if value, exists := c[key]; exists {
+		if boolValue, err := strconv.ParseBool(value); err == nil {
+			return boolValue
+		}
+		log.Printf("Invalid boolean for key %s: %v", key, value)
+	}
+	return defaultValue
+}
+
+// GetFloat64 retrieves a float64 value from the Config map based on the provided key. If the key does not exist
+// or cannot be converted to a float64, the function returns the specified default value.
+func (c Config) GetFloat64(key string, defaultValue float64) float64 {
+	if value, exists := c[key]; exists {
+		if floatValue, err := strconv.ParseFloat(value, 64); err == nil {
+			return floatValue
+		}
+		log.Printf("Invalid float for key %s: %v", key, value)
+	}
+	return defaultValue
+}
+
+// Validate checks that all the provided keys are present in the Config map. If any key is missing, it logs
+// a fatal error and exits the program. This ensures that required configuration is always set.
+func (c Config) Validate(requiredKeys ...string) {
+	for _, key := range requiredKeys {
+		if _, exists := c[key]; !exists {
+			log.Fatalf("Missing required environment variable: %s", key)
+		}
+	}
+}
+
+// Reload reloads the configuration from the environment variables and `.env` file. This can be useful
+// if the environment variables might change during runtime and you need to refresh the configuration.
+func (c *Config) Reload() {
+	*c = LoadConfig()
+}
+
+// MergeWithDefaults merges the current configuration with a default configuration map. If a key exists
+// in both, the current configuration's value is preserved.
+func (c Config) MergeWithDefaults(defaults Config) Config {
+	merged := make(Config)
+
+	for k, v := range defaults {
+		merged[k] = v
+	}
+
+	for k, v := range c {
+		merged[k] = v
+	}
+
+	return merged
+}
+
+// FilterByPrefix returns a new Config map containing only the keys that start with the specified prefix.
+// The prefix is removed from the keys in the returned map.
+func (c Config) FilterByPrefix(prefix string) Config {
+	filtered := make(Config)
+
+	for k, v := range c {
+		if strings.HasPrefix(k, prefix) {
+			filtered[strings.TrimPrefix(k, prefix)] = v
+		}
+	}
+
+	return filtered
+}