tracker/config/config.go

113 lines
2.8 KiB
Go

// Copyright 2014 The Chihaya Authors. All rights reserved.
// Use of this source code is governed by the BSD 2-Clause license,
// which can be found in the LICENSE file.
// Package config implements the configuration for a BitTorrent tracker
package config
import (
"encoding/json"
"errors"
"io"
"os"
"time"
)
// ErrMissingRequiredParam is used by drivers to indicate that an entry required
// to be within the DriverConfig.Params map is not present.
var ErrMissingRequiredParam = errors.New("A parameter that was required by a driver is not present")
// Duration wraps a time.Duration and adds JSON marshalling.
type Duration struct{ time.Duration }
// MarshalJSON transforms a duration into JSON.
func (d *Duration) MarshalJSON() ([]byte, error) {
return json.Marshal(d.String())
}
// UnmarshalJSON transform JSON into a Duration.
func (d *Duration) UnmarshalJSON(b []byte) error {
var str string
err := json.Unmarshal(b, &str)
d.Duration, err = time.ParseDuration(str)
return err
}
// DriverConfig is the configuration used to connect to a tracker.Driver or
// a backend.Driver.
type DriverConfig struct {
Name string `json:"driver"`
Params map[string]string `json:"params,omitempty"`
}
// Config is a configuration for a Server.
type Config struct {
Addr string `json:"addr"`
Tracker DriverConfig `json:"tracker"`
Backend DriverConfig `json:"backend"`
Private bool `json:"private"`
Freeleech bool `json:"freeleech"`
Whitelist bool `json:"whitelist"`
PurgeInactiveTorrents bool `json:"purge_inactive_torrents"`
Announce Duration `json:"announce"`
MinAnnounce Duration `json:"min_announce"`
RequestTimeout Duration `json:"request_timeout"`
NumWantFallback int `json:"default_num_want"`
}
// DefaultConfig is a configuration that can be used as a fallback value.
var DefaultConfig = Config{
Addr: "127.0.0.1:6881",
Tracker: DriverConfig{
Name: "memory",
},
Backend: DriverConfig{
Name: "noop",
},
Private: false,
Freeleech: false,
Whitelist: false,
PurgeInactiveTorrents: true,
Announce: Duration{30 * time.Minute},
MinAnnounce: Duration{15 * time.Minute},
RequestTimeout: Duration{10 * time.Second},
NumWantFallback: 50,
}
// Open is a shortcut to open a file, read it, and generate a Config.
// It supports relative and absolute paths. Given "", it returns DefaultConfig.
func Open(path string) (*Config, error) {
if path == "" {
return &DefaultConfig, nil
}
f, err := os.Open(os.ExpandEnv(path))
if err != nil {
return nil, err
}
defer f.Close()
conf, err := Decode(f)
if err != nil {
return nil, err
}
return conf, nil
}
// Decode casts an io.Reader into a JSONDecoder and decodes it into a *Config.
func Decode(r io.Reader) (*Config, error) {
conf := &Config{}
err := json.NewDecoder(r).Decode(conf)
if err != nil {
return nil, err
}
return conf, nil
}