chore: allow integer env vars (#1289)

Author: RTann

pkg/env/integersetting.go

@@ -0,0 +1,33 @@
+package env
+
+import (
+	"strconv"
+)
+
+// IntegerSetting represents an environment variable which should be parsed into an integer.
+type IntegerSetting interface {
+	Setting
+	Int() int
+}
+
+type integerSetting struct {
+	Setting
+	defaultValue int
+}
+
+// Int returns the int object represented by the environment variable.
+func (s *integerSetting) Int() int {
+	v, err := strconv.Atoi(s.Value())
+	if err != nil {
+		return s.defaultValue
+	}
+	return v
+}
+
+// RegisterIntegerSetting globally registers and returns a new integer setting.
+func RegisterIntegerSetting(envVar string, defaultValue int, opts ...SettingOption) IntegerSetting {
+	return &integerSetting{
+		Setting:      RegisterSetting(envVar, append(opts, WithDefault(strconv.Itoa(defaultValue)))...),
+		defaultValue: defaultValue,
+	}
+}