diff options
| -rw-r--r-- | caddy.go | 102 | ||||
| -rw-r--r-- | modules.go | 8 | ||||
| -rw-r--r-- | modules/caddyhttp/caddylog/log.go | 22 |
3 files changed, 122 insertions, 10 deletions
@@ -10,13 +10,34 @@ import ( "time" ) -var currentCfg *Config -var currentCfgMu sync.Mutex - // Start runs Caddy with the given config. func Start(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() + + // prepare the config for use cfg.runners = make(map[string]Runner) + 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 in case this + // function returns an error, we need to put + // the "old" one back where we found it + var err error + oldModuleInstances := moduleInstances + defer func() { + if err != nil { + moduleInstances = oldModuleInstances + } + }() + moduleInstances = make(map[string][]interface{}) + // load (decode) each runner module for modName, rawMsg := range cfg.Modules { val, err := LoadModule(modName, rawMsg) if err != nil { @@ -34,19 +55,60 @@ func Start(cfg Config) error { } } - // shut down down the old ones + // shut down down the old runners currentCfgMu.Lock() if currentCfg != nil { - for _, r := range currentCfg.runners { + for name, r := range currentCfg.runners { err := r.Cancel() if err != nil { - log.Println(err) + log.Printf("[ERROR] cancel %s: %v", name, err) } } } + oldCfg := currentCfg currentCfg = &cfg currentCfgMu.Unlock() + // invoke unload callbacks on old configuration + for modName := range oldModuleInstances { + mod, err := GetModule(modName) + if err != nil { + return err + } + if mod.OnUnload != nil { + var unloadingState interface{} + if oldCfg != nil { + unloadingState = oldCfg.moduleStates[modName] + } + err := mod.OnUnload(unloadingState) + if err != nil { + log.Printf("[ERROR] module OnUnload: %s: %v", modName, err) + continue + } + } + } + + // invoke load callbacks on new configuration + for modName, instances := range moduleInstances { + mod, err := GetModule(modName) + if err != nil { + return err + } + if mod.OnLoad != nil { + var priorState interface{} + if oldCfg != nil { + priorState = oldCfg.moduleStates[modName] + } + modState, err := mod.OnLoad(instances, priorState) + if err != nil { + return fmt.Errorf("module OnLoad: %s: %v", modName, err) + } + if modState != nil { + cfg.moduleStates[modName] = modState + } + } + } + // shut down listeners that are no longer being used listenersMu.Lock() for key, info := range listeners { @@ -74,7 +136,15 @@ type Runner interface { type Config struct { TestVal string `json:"testval"` Modules map[string]json.RawMessage `json:"modules"` + + // runners stores the decoded Modules values, + // keyed by module name. runners map[string]Runner + + // moduleStates stores the optional "global" state + // values of every module used by this configuration, + // keyed by module name. + moduleStates map[string]interface{} } // Duration is a JSON-string-unmarshable duration type. @@ -95,3 +165,23 @@ func (d *Duration) UnmarshalJSON(b []byte) error { func (d Duration) MarshalJSON() ([]byte, error) { return []byte(fmt.Sprintf(`"%s"`, time.Duration(d).String())), nil } + +// currentCfg is the currently-loaded configuration. +var ( + currentCfg *Config + currentCfgMu sync.Mutex +) + +// 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 +var startMu sync.Mutex diff --git a/modules.go b/modules.go index 46dfbe827..ac41f16ae 100644 --- a/modules.go +++ b/modules.go @@ -11,8 +11,10 @@ import ( // Module is a module. type Module struct { - Name string - New func() (interface{}, error) + Name string + New func() (interface{}, error) + OnLoad func(instances []interface{}, priorState interface{}) (newState interface{}, err error) + OnUnload func(state interface{}) error } func (m Module) String() string { return m.Name } @@ -145,6 +147,8 @@ func LoadModule(name string, rawMsg json.RawMessage) (interface{}, error) { } } + moduleInstances[mod.Name] = append(moduleInstances[mod.Name], val) + return val, nil } diff --git a/modules/caddyhttp/caddylog/log.go b/modules/caddyhttp/caddylog/log.go index 5bbab2a72..f7bc9fd32 100644 --- a/modules/caddyhttp/caddylog/log.go +++ b/modules/caddyhttp/caddylog/log.go @@ -12,13 +12,31 @@ import ( func init() { caddy2.RegisterModule(caddy2.Module{ Name: "http.middleware.log", - New: func() (interface{}, error) { return &Log{}, nil }, + New: func() (interface{}, error) { return new(Log), nil }, + OnLoad: func(instances []interface{}, priorState interface{}) (interface{}, error) { + var counter int + if priorState != nil { + counter = priorState.(int) + } + counter++ + for _, inst := range instances { + logInst := inst.(*Log) + logInst.counter = counter + } + log.Println("State is now:", counter) + return counter, nil + }, + OnUnload: func(state interface{}) error { + log.Println("Closing log files, state:", state) + return nil + }, }) } // Log implements a simple logging middleware. type Log struct { Filename string + counter int } func (l *Log) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.Handler) error { @@ -28,7 +46,7 @@ func (l *Log) ServeHTTP(w http.ResponseWriter, r *http.Request, next caddyhttp.H return err } - log.Println("latency:", time.Now().Sub(start)) + log.Println("latency:", time.Now().Sub(start), l.counter) return nil } |