From 1a20a7d35f40bd9daab5b2f35dfb76f10109a2f1 Mon Sep 17 00:00:00 2001
From: Derrick Hammer <derrick@derrickhammer.com>
Date: Wed, 28 Feb 2024 08:03:36 -0500
Subject: [PATCH] refactor: define a cluster config with redis and etcd support

---
 config/cluster.go  | 70 ++++++++++++++++++++++++++++++++++++++++++++++
 config/config.go   |  2 +-
 config/core.go     |  1 +
 config/database.go |  6 ----
 config/etcd.go     | 15 ++++++++++
 5 files changed, 87 insertions(+), 7 deletions(-)
 create mode 100644 config/cluster.go
 create mode 100644 config/etcd.go

diff --git a/config/cluster.go b/config/cluster.go
new file mode 100644
index 0000000..3e590c6
--- /dev/null
+++ b/config/cluster.go
@@ -0,0 +1,70 @@
+package config
+
+import (
+	"errors"
+	"reflect"
+
+	"github.com/mitchellh/mapstructure"
+)
+
+type ClusterConfig struct {
+	Enabled bool         `mapstructure:"enabled"`
+	Redis   *RedisConfig `mapstructure:"redis"`
+	Etcd    *EtcdConfig  `mapstructure:"etcd"`
+}
+
+type RedisConfig struct {
+	Address  string `mapstructure:"address"`
+	Password string `mapstructure:"password"`
+	DB       int    `mapstructure:"db"`
+}
+
+func (r *RedisConfig) Validate() error {
+	if r.Address == "" {
+		return errors.New("address is required")
+	}
+	return nil
+}
+
+func clusterConfigHook() mapstructure.DecodeHookFuncType {
+	return func(f reflect.Type, t reflect.Type, data interface{}) (interface{}, error) {
+		if f.Kind() != reflect.Map || t != reflect.TypeOf(&ClusterConfig{}) {
+			return data, nil
+		}
+
+		var clusterConfig ClusterConfig
+		if err := mapstructure.Decode(data, &clusterConfig); err != nil {
+			return nil, err
+		}
+
+		// Check if the input data map includes "redis" configuration
+		if opts, ok := data.(map[string]interface{})["redis"].(map[string]interface{}); ok && opts != nil {
+			var redisOptions RedisConfig
+			if err := mapstructure.Decode(opts, &redisOptions); err != nil {
+				return nil, err
+			}
+
+			if err := redisOptions.Validate(); err != nil {
+				return nil, err
+			}
+
+			clusterConfig.Redis = &redisOptions
+		}
+
+		// Check if the input data map includes "etcd" configuration
+		if opts, ok := data.(map[string]interface{})["etcd"].(map[string]interface{}); ok && opts != nil {
+			var etcdOptions EtcdConfig
+			if err := mapstructure.Decode(opts, &etcdOptions); err != nil {
+				return nil, err
+			}
+
+			if err := etcdOptions.Validate(); err != nil {
+				return nil, err
+			}
+
+			clusterConfig.Etcd = &etcdOptions
+		}
+
+		return &clusterConfig, nil
+	}
+}
diff --git a/config/config.go b/config/config.go
index 50e2f79..ac3184f 100644
--- a/config/config.go
+++ b/config/config.go
@@ -47,7 +47,7 @@ func NewManager() (*Manager, error) {
 		return nil, err
 	}
 
-	err = v.Unmarshal(&config, viper.DecodeHook(cacheConfigHook()))
+	err = v.Unmarshal(&config, viper.DecodeHook(clusterConfigHook()), viper.DecodeHook(cacheConfigHook()))
 	if err != nil {
 		return nil, err
 	}
diff --git a/config/core.go b/config/core.go
index 15eaf9b..5037938 100644
--- a/config/core.go
+++ b/config/core.go
@@ -13,4 +13,5 @@ type CoreConfig struct {
 	Storage         StorageConfig  `mapstructure:"storage"`
 	Protocols       []string       `mapstructure:"protocols"`
 	Mail            MailConfig     `mapstructure:"mail"`
+	Clustered       *ClusterConfig `mapstructure:"clustered"`
 }
diff --git a/config/database.go b/config/database.go
index 47f1ce1..4581f32 100644
--- a/config/database.go
+++ b/config/database.go
@@ -21,12 +21,6 @@ type CacheConfig struct {
 	Options interface{} `mapstructure:"options"`
 }
 
-type RedisConfig struct {
-	Address  string `mapstructure:"address"`
-	Password string `mapstructure:"password"`
-	DB       int    `mapstructure:"db"`
-}
-
 type MemoryConfig struct {
 }
 
diff --git a/config/etcd.go b/config/etcd.go
new file mode 100644
index 0000000..01a9957
--- /dev/null
+++ b/config/etcd.go
@@ -0,0 +1,15 @@
+package config
+
+import "errors"
+
+type EtcdConfig struct {
+	Endpoints   []string `mapstructure:"endpoints"`
+	DialTimeout int      `mapstructure:"dial_timeout"`
+}
+
+func (r *EtcdConfig) Validate() error {
+	if len(r.Endpoints) == 0 {
+		return errors.New("endpoints is required")
+	}
+	return nil
+}