feat: config files

.gitignore

@@ -114,4 +114,6 @@ fabric.properties
 
 # End of https://www.toptal.com/developers/gitignore/api/goland+all,go
 
-build
+build
+
+config.json

cmd/server/server.go

@@ -2,7 +2,12 @@ package main
 
 import (
 	"flag"
+	"git.brettb.xyz/goinv/server/internal/config"
+	"github.com/knadh/koanf/parsers/json"
+	"github.com/knadh/koanf/providers/env"
+	"github.com/knadh/koanf/providers/file"
 	"log"
+	"strings"
 
 	"git.brettb.xyz/goinv/server/internal/api"
 	"git.brettb.xyz/goinv/server/internal/storage"
@@ -13,9 +18,22 @@ func main() {
 	seed := flag.Bool("seed", false, "seed the database")
 	flag.Parse()
 
-	datastore, err := storage.NewDataStorePG("127.0.0.1", "postgres", "password", "em_test", "disable") // TODO: CONFIGURATION
+	config.LoadConfig(file.Provider("config.json"), json.Parser())
+	config.LoadConfig(env.Provider("GOINV_SRV_", ".", func(s string) string {
+		return strings.Replace(strings.ToLower(
+			strings.TrimPrefix(s, "GOINV_SRV_")), "_", ".", -1,
+		)
+	}), nil)
+
+	var cfg config.Config
+	err := config.Unmarshal(&cfg)
 	if err != nil {
-		panic(err)
+		log.Fatalf("could not load config: %v", err)
+	}
+
+	datastore, err := storage.NewDataStorePG(cfg.DB.Host, cfg.DB.Username, cfg.DB.Password, cfg.DB.Database, cfg.DB.SSLMode)
+	if err != nil {
+		log.Fatalf("could not connect to database: %v", err)
 	}
 
 	if *seed {

config.example.json

@@ -0,0 +1,9 @@
+{
+  "db": {
+    "host": "127.0.0.1",
+    "username": "postgres",
+    "password": "password",
+    "database": "em_test",
+    "ssl_mode": "disable"
+  }
+}

internal/config/config.go

@@ -0,0 +1,25 @@
+package config
+
+import "github.com/knadh/koanf"
+
+var (
+	K = koanf.New(".")
+)
+
+type Config struct {
+	DB struct {
+		Host     string `koanf:"host"`
+		Username string `koanf:"username"`
+		Password string `koanf:"password"`
+		Database string `koanf:"database"`
+		SSLMode  string `koanf:"ssl_mode"`
+	} `koanf:"db"`
+}
+
+func LoadConfig(provider koanf.Provider, parser koanf.Parser) error {
+	return K.Load(provider, parser)
+}
+
+func Unmarshal(o interface{}) error {
+	return K.Unmarshal("", o)
+}