package caddy2 import ( "encoding/json" "fmt" "log" "strings" "sync" "sync/atomic" "time" "github.com/mholt/certmagic" ) // Run runs Caddy with the given config. func Run(cfg *Config) error { // allow only one call to Start at a time, // since various calls to LoadModule() // access shared map moduleInstances startMu.Lock() defer startMu.Unlock() // because we will need to roll back any state // modifications if this function errors, we // keep a single error value and scope all // sub-operations to their own functions to // ensure this error value does not get // overridden or missed when it should have // been set by a short assignment var err error // prepare the new config for use cfg.apps = make(map[string]App) cfg.moduleStates = make(map[string]interface{}) // reset the shared moduleInstances map; but // keep a temporary reference to the current // one so we can transfer over any necessary // state to the new modules or to roll back // if necessary oldModuleInstances := moduleInstances defer func() { if err != nil { moduleInstances = oldModuleInstances } }() moduleInstances = make(map[string][]interface{}) // set up storage and make it CertMagic's default storage, too err = func() error { if cfg.StorageRaw != nil { val, err := LoadModuleInline("system", "caddy.storage", cfg.StorageRaw) if err != nil { return fmt.Errorf("loading storage module: %v", err) } stor, err := val.(StorageConverter).CertMagicStorage() if err != nil { return fmt.Errorf("creating storage value: %v", err) } cfg.storage = stor cfg.StorageRaw = nil // allow GC to deallocate - TODO: Does this help? } if cfg.storage == nil { cfg.storage = &certmagic.FileStorage{Path: dataDir()} } certmagic.Default.Storage = cfg.storage return nil }() if err != nil { return err } // Load, Provision, Validate err = func() error { for modName, rawMsg := range cfg.AppsRaw { val, err := LoadModule(modName, rawMsg) if err != nil { return fmt.Errorf("loading app module '%s': %v", modName, err) } cfg.apps[modName] = val.(App) } return nil }() if err != nil { return err } // swap old config with the new one, and // roll back this change if anything fails currentCfgMu.Lock() oldCfg := currentCfg currentCfg = cfg currentCfgMu.Unlock() defer func() { if err != nil { currentCfgMu.Lock() currentCfg = oldCfg currentCfgMu.Unlock() } }() // Start err = func() error { h := Handle{cfg} for name, a := range cfg.apps { err := a.Start(h) if err != nil { for otherAppName, otherApp := range cfg.apps { err := otherApp.Stop() if err != nil { log.Printf("aborting app %s: %v", otherAppName, err) } } return fmt.Errorf("%s app module: start: %v", name, err) } } return nil }() if err != nil { return err } // Stop if oldCfg != nil { for name, a := range oldCfg.apps { err := a.Stop() if err != nil { log.Printf("[ERROR] stop %s: %v", name, err) } } } // shut down listeners that are no longer being used err = func() error { listenersMu.Lock() for key, info := range listeners { if atomic.LoadInt32(&info.usage) == 0 { err := info.ln.Close() if err != nil { log.Printf("[ERROR] closing listener %s: %v", info.ln.Addr(), err) continue } delete(listeners, key) } } listenersMu.Unlock() return nil }() if err != nil { return err } return nil } // App is a thing that Caddy runs. type App interface { Start(Handle) error Stop() error } // Config represents a Caddy configuration. type Config struct { StorageRaw json.RawMessage `json:"storage"` storage certmagic.Storage TestVal string `json:"testval"` AppsRaw map[string]json.RawMessage `json:"apps"` // apps stores the decoded Apps values, // keyed by module name. apps map[string]App // moduleStates stores the optional "global" state // values of every module used by this configuration, // keyed by module name. moduleStates map[string]interface{} } // Handle allows app modules to access // the top-level Config in a controlled // manner without needing to rely on // global state. type Handle struct { current *Config } // App returns the configured app named name. If no app with // that name is currently configured, a new empty one will be // instantiated. (The app module must still be registered.) func (h Handle) App(name string) (interface{}, error) { if app, ok := h.current.apps[name]; ok { return app, nil } modVal, err := LoadModule(name, nil) if err != nil { return nil, fmt.Errorf("instantiating new module %s: %v", name, err) } h.current.apps[name] = modVal.(App) return modVal, nil } // GetStorage returns the configured Caddy storage implementation. // If no storage implementation is explicitly configured, the // default one is returned instead, as long as there is a current // configuration loaded. func GetStorage() certmagic.Storage { currentCfgMu.RLock() defer currentCfgMu.RUnlock() if currentCfg == nil { return nil } return currentCfg.storage } // Duration is a JSON-string-unmarshable duration type. type Duration time.Duration // UnmarshalJSON satisfies json.Unmarshaler. func (d *Duration) UnmarshalJSON(b []byte) error { dd, err := time.ParseDuration(strings.Trim(string(b), `"`)) if err != nil { return err } cd := Duration(dd) d = &cd return nil } // CtxKey is a value type for use with context.WithValue. type CtxKey string // currentCfg is the currently-loaded configuration. var ( currentCfg *Config currentCfgMu sync.RWMutex ) // moduleInstances stores the individual instantiated // values of modules, keyed by module name. The list // of instances of each module get passed into the // respective module's OnLoad callback, so they can // set up any global state and/or make sure their // configuration, when viewed as a whole, is valid. // Since this list is shared, only one Start() routine // must be allowed to happen at any given time. var moduleInstances = make(map[string][]interface{}) // startMu ensures that only one Start() happens at a time. // This is important since moduleInstances is shared state. var startMu sync.Mutex