list_store.go

/*
 * Copyright 2018 - 2020 Christian Müller <dev@c-mueller.xyz>
 *
 * 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 ads

import (
	"encoding/json"
	"io/ioutil"
	"os"
	"time"
)

type StoredListConfiguration struct {
	UpdateTimestamp int      `json:"update_timestamp"`
	BlacklistURLs   []string `json:"blacklist_urls"`
	WhitelistURLs   []string `json:"whitelist_urls"`
	Blacklist       ListMap  `json:"blacklist"`
	Whitelist       ListMap  `json:"whitelist"`
}

func ReadListConfiguration(path string) (*StoredListConfiguration, error) {
	file, err := os.OpenFile(path, os.O_RDONLY, 0666)
	if err != nil {
		return nil, err
	}
	defer file.Close()

	compressedData, err := ioutil.ReadAll(file)
	if err != nil {
		return nil, err
	}

	data, err := gunzip(compressedData)

	var config StoredListConfiguration

	err = json.Unmarshal(data, &config)
	if err != nil {
		return nil, err
	}

	return &config, nil
}

func (s *StoredListConfiguration) Persist(path string) error {
	data, err := json.Marshal(s)
	if err != nil {
		return err
	}

	compressed, err := gzip(data)
	if err != nil {
		return err
	}

	file, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR, 0666)
	if err != nil {
		return err
	}
	defer file.Close()

	_, err = file.Write(compressed)

	return err
}

func (s *StoredListConfiguration) NeedsUpdate(updateDuration time.Duration) bool {
	return time.Now().After(time.Unix(int64(s.UpdateTimestamp), 0).Add(updateDuration))
}