add config package

go.mod

@@ -9,6 +9,7 @@ require (
 	golang.org/x/crypto v0.0.0-20210921155107-089bfa567519
 	google.golang.org/api v0.60.0
 	gopkg.in/tucnak/telebot.v2 v2.4.0
+	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c
 )
 
 require (

go.sum

@@ -559,6 +559,7 @@ gopkg.in/tucnak/telebot.v2 v2.4.0 h1:nOeqOWnOAD3dzbKW+NRumd8zjj5vrWwSa0WRTxvgfag
 gopkg.in/tucnak/telebot.v2 v2.4.0/go.mod h1:BgaIIx50PSRS9pG59JH+geT82cfvoJU/IaI5TJdN3v8=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.3/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190106161140-3f1c8253044a/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

pkg/config/config.go

@@ -0,0 +1,65 @@
+// Copyright 2021 Mikhail Borovikov and The Secretable Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+
+// 	http://www.apache.org/licenses/LICENSE-2.0
+
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package config
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"os"
+	"secretable/pkg/log"
+
+	"gopkg.in/yaml.v3"
+)
+
+type Config struct {
+	TelegramBotToken  string `yaml:"telegram_bot_token"`
+	GoogleCredentials string `yaml:"google_credentials_file"`
+	SpreadsheetID     string `yaml:"spreadsheet_id"`
+	CleanupTimeout    int    `yaml:"cleanup_timeout"`
+	Unencrypted       bool   `yaml:"unencrypted"`
+	Salt              string `yaml:"salt"`
+}
+
+func ParseFromFile(path string) (config *Config, err error) {
+	config = new(Config)
+	file, err := os.Open(path)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			if file, err = os.Create(path); err != nil {
+				return nil, err
+			}
+			log.Info("📝 Created config file " + path)
+		} else {
+			return nil, err
+		}
+	}
+
+	defer file.Close()
+
+	if err = yaml.NewDecoder(file).Decode(config); err != nil && err != io.EOF {
+		return nil, err
+	}
+
+	return config, nil
+}
+
+func UpdateFile(path string, config *Config) error {
+	buf := bytes.NewBuffer([]byte{})
+	if err := yaml.NewEncoder(buf).Encode(config); err != nil {
+		return nil
+	}
+	return os.WriteFile(path, buf.Bytes(), os.ModePerm)
+}