Restructure project layout

internal/configuration/configuration.go

@@ -0,0 +1,66 @@
+package configuration
+
+import (
+	"github.com/jinzhu/configor"
+)
+
+// Argon2Config holds the parameters used for creating hashes with Argon2.
+type Argon2Config struct {
+	Memory      uint32 `default:"131072"`
+	Iterations  uint32 `default:"4"`
+	Parallelism uint8  `default:"4"`
+	SaltLength  uint32 `default:"16"`
+	KeyLength   uint32 `default:"32"`
+}
+
+// CryptoConfig holds the parameters used for creating hashes.
+type CryptoConfig struct {
+	Argon2 Argon2Config
+}
+
+// Configuration holds values that can be configured by the user.
+type Configuration struct {
+	Debug bool `default:"false"`
+	HTTP  struct {
+		ListenAddress string `default:""`
+		Port          int    `default:"8080"`
+	}
+	Database struct {
+		Dialect    string `default:"sqlite3"`
+		Connection string `default:"pushbits.db"`
+	}
+	Admin struct {
+		Name     string `default:"admin"`
+		Password string `default:"admin"`
+		MatrixID string `required:"true"`
+	}
+	Matrix struct {
+		Homeserver string `default:"https://matrix.org"`
+		Username   string `required:"true"`
+		Password   string `required:"true"`
+	}
+	Security struct {
+		CheckHIBP bool `default:"false"`
+	}
+	Crypto CryptoConfig
+}
+
+func configFiles() []string {
+	return []string{"config.yml"}
+}
+
+// Get returns the configuration extracted from env variables or config file.
+func Get() *Configuration {
+	config := &Configuration{}
+
+	err := configor.New(&configor.Config{
+		Environment:          "production",
+		ENVPrefix:            "PUSHBITS",
+		ErrorOnUnmatchedKeys: true,
+	}).Load(config, configFiles()...)
+	if err != nil {
+		panic(err)
+	}
+
+	return config
+}