feat: initial commit

internal/config/environment.go

@@ -0,0 +1,125 @@
+package config
+
+import (
+	"os"
+	"regexp"
+	"strconv"
+
+	"github.com/pkg/errors"
+	"gopkg.in/yaml.v3"
+)
+
+var reVar = regexp.MustCompile(`^\${(\w+)}$`)
+
+type InterpolatedString string
+
+func (is *InterpolatedString) UnmarshalYAML(value *yaml.Node) error {
+	var str string
+
+	if err := value.Decode(&str); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if match := reVar.FindStringSubmatch(str); len(match) > 0 {
+		*is = InterpolatedString(os.Getenv(match[1]))
+	} else {
+		*is = InterpolatedString(str)
+	}
+
+	return nil
+}
+
+type InterpolatedInt int
+
+func (ii *InterpolatedInt) UnmarshalYAML(value *yaml.Node) error {
+	var str string
+
+	if err := value.Decode(&str); err != nil {
+		return errors.Wrapf(err, "could not decode value '%v' (line '%d') into string", value.Value, value.Line)
+	}
+
+	if match := reVar.FindStringSubmatch(str); len(match) > 0 {
+		str = os.Getenv(match[1])
+	}
+
+	intVal, err := strconv.ParseInt(str, 10, 32)
+	if err != nil {
+		return errors.Wrapf(err, "could not parse int '%v',  line '%d'", str, value.Line)
+	}
+
+	*ii = InterpolatedInt(int(intVal))
+
+	return nil
+}
+
+type InterpolatedBool bool
+
+func (ib *InterpolatedBool) UnmarshalYAML(value *yaml.Node) error {
+	var str string
+
+	if err := value.Decode(&str); err != nil {
+		return errors.Wrapf(err, "could not decode value '%v' (line '%d') into string", value.Value, value.Line)
+	}
+
+	if match := reVar.FindStringSubmatch(str); len(match) > 0 {
+		str = os.Getenv(match[1])
+	}
+
+	boolVal, err := strconv.ParseBool(str)
+	if err != nil {
+		return errors.Wrapf(err, "could not parse bool '%v',  line '%d'", str, value.Line)
+	}
+
+	*ib = InterpolatedBool(boolVal)
+
+	return nil
+}
+
+type InterpolatedMap map[string]interface{}
+
+func (im *InterpolatedMap) UnmarshalYAML(value *yaml.Node) error {
+	var data map[string]interface{}
+
+	if err := value.Decode(&data); err != nil {
+		return errors.Wrapf(err, "could not decode value '%v' (line '%d') into map", value.Value, value.Line)
+	}
+
+	for key, value := range data {
+		strVal, ok := value.(string)
+		if !ok {
+			continue
+		}
+
+		if match := reVar.FindStringSubmatch(strVal); len(match) > 0 {
+			strVal = os.Getenv(match[1])
+		}
+
+		data[key] = strVal
+	}
+
+	*im = data
+
+	return nil
+}
+
+type InterpolatedStringSlice []string
+
+func (iss *InterpolatedStringSlice) UnmarshalYAML(value *yaml.Node) error {
+	var data []string
+
+	if err := value.Decode(&data); err != nil {
+		return errors.Wrapf(err, "could not decode value '%v' (line '%d') into map", value.Value, value.Line)
+	}
+
+	for index, value := range data {
+		if match := reVar.FindStringSubmatch(value); len(match) > 0 {
+			value = os.Getenv(match[1])
+		}
+
+		data[index] = value
+	}
+
+	*iss = data
+
+	return nil
+}