AdGuardHome/internal/next/configmgr/configmgr.go

302 lines
8.0 KiB
Go

// Package configmgr defines the AdGuard Home on-disk configuration entities and
// configuration manager.
//
// TODO(a.garipov): Add tests.
package configmgr
import (
"context"
"fmt"
"io/fs"
"net/netip"
"os"
"sync"
"time"
"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
"github.com/AdguardTeam/AdGuardHome/internal/next/dnssvc"
"github.com/AdguardTeam/AdGuardHome/internal/next/websvc"
"github.com/AdguardTeam/golibs/errors"
"github.com/AdguardTeam/golibs/log"
"github.com/AdguardTeam/golibs/timeutil"
"github.com/google/renameio/v2/maybe"
"golang.org/x/exp/slices"
"gopkg.in/yaml.v3"
)
// Configuration Manager
// Manager handles full and partial changes in the configuration, persisting
// them to disk if necessary.
//
// TODO(a.garipov): Support missing configs and default values.
type Manager struct {
// updMu makes sure that at most one reconfiguration is performed at a time.
// updMu protects all fields below.
updMu *sync.RWMutex
// dns is the DNS service.
dns *dnssvc.Service
// Web is the Web API service.
web *websvc.Service
// current is the current configuration.
current *config
// fileName is the name of the configuration file.
fileName string
}
// Validate returns an error if the configuration file with the given name does
// not exist or is invalid.
func Validate(fileName string) (err error) {
conf, err := read(fileName)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return err
}
// Don't wrap the error, because it's informative enough as is.
return conf.validate()
}
// Config contains the configuration parameters for the configuration manager.
type Config struct {
// Frontend is the filesystem with the frontend files.
Frontend fs.FS
// WebAddr is the initial or override address for the Web UI. It is not
// written to the configuration file.
WebAddr netip.AddrPort
// Start is the time of start of AdGuard Home.
Start time.Time
// FileName is the path to the configuration file.
FileName string
}
// New creates a new *Manager that persists changes to the file pointed to by
// c.FileName. It reads the configuration file and populates the service
// fields. c must not be nil.
func New(ctx context.Context, c *Config) (m *Manager, err error) {
conf, err := read(c.FileName)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return nil, err
}
err = conf.validate()
if err != nil {
return nil, fmt.Errorf("validating config: %w", err)
}
m = &Manager{
updMu: &sync.RWMutex{},
current: conf,
fileName: c.FileName,
}
err = m.assemble(ctx, conf, c.Frontend, c.WebAddr, c.Start)
if err != nil {
return nil, fmt.Errorf("creating config manager: %w", err)
}
return m, nil
}
// read reads and decodes configuration from the provided filename.
func read(fileName string) (conf *config, err error) {
defer func() { err = errors.Annotate(err, "reading config: %w") }()
conf = &config{}
f, err := os.Open(fileName)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return nil, err
}
defer func() { err = errors.WithDeferred(err, f.Close()) }()
err = yaml.NewDecoder(f).Decode(conf)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return nil, err
}
return conf, nil
}
// assemble creates all services and puts them into the corresponding fields.
// The fields of conf must not be modified after calling assemble.
func (m *Manager) assemble(
ctx context.Context,
conf *config,
frontend fs.FS,
webAddr netip.AddrPort,
start time.Time,
) (err error) {
dnsConf := &dnssvc.Config{
Addresses: conf.DNS.Addresses,
BootstrapServers: conf.DNS.BootstrapDNS,
UpstreamServers: conf.DNS.UpstreamDNS,
DNS64Prefixes: conf.DNS.DNS64Prefixes,
UpstreamTimeout: conf.DNS.UpstreamTimeout.Duration,
BootstrapPreferIPv6: conf.DNS.BootstrapPreferIPv6,
UseDNS64: conf.DNS.UseDNS64,
}
err = m.updateDNS(ctx, dnsConf)
if err != nil {
return fmt.Errorf("assembling dnssvc: %w", err)
}
webSvcConf := &websvc.Config{
Pprof: &websvc.PprofConfig{
Port: conf.HTTP.Pprof.Port,
Enabled: conf.HTTP.Pprof.Enabled,
},
ConfigManager: m,
Frontend: frontend,
// TODO(a.garipov): Fill from config file.
TLS: nil,
Start: start,
Addresses: conf.HTTP.Addresses,
SecureAddresses: conf.HTTP.SecureAddresses,
OverrideAddress: webAddr,
Timeout: conf.HTTP.Timeout.Duration,
ForceHTTPS: conf.HTTP.ForceHTTPS,
}
err = m.updateWeb(ctx, webSvcConf)
if err != nil {
return fmt.Errorf("assembling websvc: %w", err)
}
return nil
}
// write writes the current configuration to disk.
func (m *Manager) write() (err error) {
b, err := yaml.Marshal(m.current)
if err != nil {
return fmt.Errorf("encoding: %w", err)
}
err = maybe.WriteFile(m.fileName, b, 0o644)
if err != nil {
return fmt.Errorf("writing: %w", err)
}
log.Info("configmgr: written to %q", m.fileName)
return nil
}
// DNS returns the current DNS service. It is safe for concurrent use.
func (m *Manager) DNS() (dns agh.ServiceWithConfig[*dnssvc.Config]) {
m.updMu.RLock()
defer m.updMu.RUnlock()
return m.dns
}
// UpdateDNS implements the [websvc.ConfigManager] interface for *Manager. The
// fields of c must not be modified after calling UpdateDNS.
func (m *Manager) UpdateDNS(ctx context.Context, c *dnssvc.Config) (err error) {
m.updMu.Lock()
defer m.updMu.Unlock()
// TODO(a.garipov): Update and write the configuration file. Return an
// error if something went wrong.
err = m.updateDNS(ctx, c)
if err != nil {
return fmt.Errorf("reassembling dnssvc: %w", err)
}
m.updateCurrentDNS(c)
return m.write()
}
// updateDNS recreates the DNS service. m.updMu is expected to be locked.
func (m *Manager) updateDNS(ctx context.Context, c *dnssvc.Config) (err error) {
if prev := m.dns; prev != nil {
err = prev.Shutdown(ctx)
if err != nil {
return fmt.Errorf("shutting down dns svc: %w", err)
}
}
svc, err := dnssvc.New(c)
if err != nil {
return fmt.Errorf("creating dns svc: %w", err)
}
m.dns = svc
return nil
}
// updateCurrentDNS updates the DNS configuration in the current config.
func (m *Manager) updateCurrentDNS(c *dnssvc.Config) {
m.current.DNS.Addresses = slices.Clone(c.Addresses)
m.current.DNS.BootstrapDNS = slices.Clone(c.BootstrapServers)
m.current.DNS.UpstreamDNS = slices.Clone(c.UpstreamServers)
m.current.DNS.DNS64Prefixes = slices.Clone(c.DNS64Prefixes)
m.current.DNS.UpstreamTimeout = timeutil.Duration{Duration: c.UpstreamTimeout}
m.current.DNS.BootstrapPreferIPv6 = c.BootstrapPreferIPv6
m.current.DNS.UseDNS64 = c.UseDNS64
}
// Web returns the current web service. It is safe for concurrent use.
func (m *Manager) Web() (web agh.ServiceWithConfig[*websvc.Config]) {
m.updMu.RLock()
defer m.updMu.RUnlock()
return m.web
}
// UpdateWeb implements the [websvc.ConfigManager] interface for *Manager. The
// fields of c must not be modified after calling UpdateWeb.
func (m *Manager) UpdateWeb(ctx context.Context, c *websvc.Config) (err error) {
m.updMu.Lock()
defer m.updMu.Unlock()
err = m.updateWeb(ctx, c)
if err != nil {
return fmt.Errorf("reassembling websvc: %w", err)
}
m.updateCurrentWeb(c)
return m.write()
}
// updateWeb recreates the web service. m.upd is expected to be locked.
func (m *Manager) updateWeb(ctx context.Context, c *websvc.Config) (err error) {
if prev := m.web; prev != nil {
err = prev.Shutdown(ctx)
if err != nil {
return fmt.Errorf("shutting down web svc: %w", err)
}
}
m.web, err = websvc.New(c)
if err != nil {
return fmt.Errorf("creating web svc: %w", err)
}
return nil
}
// updateCurrentWeb updates the web configuration in the current config.
func (m *Manager) updateCurrentWeb(c *websvc.Config) {
// TODO(a.garipov): Update pprof from API?
m.current.HTTP.Addresses = slices.Clone(c.Addresses)
m.current.HTTP.SecureAddresses = slices.Clone(c.SecureAddresses)
m.current.HTTP.Timeout = timeutil.Duration{Duration: c.Timeout}
m.current.HTTP.ForceHTTPS = c.ForceHTTPS
}