package pipeline import ( "git.noahlan.cn/northlan/ngs/internal/message" "git.noahlan.cn/northlan/ngs/session" "sync" ) type ( // Message is the alias of `message.Message` Message = message.Message Func func(s *session.Session, msg *message.Message) error Pipeline interface { Outbound() Channel Inbound() Channel } pipeline struct { outbound, inbound *pipelineChannel } Channel interface { PushFront(h Func) PushBack(h Func) Process(s *session.Session, msg *message.Message) error } pipelineChannel struct { mu sync.RWMutex handlers []Func } ) func New() Pipeline { return &pipeline{ outbound: &pipelineChannel{}, inbound: &pipelineChannel{}, } } func (p *pipeline) Outbound() Channel { return p.outbound } func (p *pipeline) Inbound() Channel { return p.inbound } // PushFront push a function to the front of the pipeline func (p *pipelineChannel) PushFront(h Func) { p.mu.Lock() defer p.mu.Unlock() handlers := make([]Func, len(p.handlers)+1) handlers[0] = h copy(handlers[1:], p.handlers) p.handlers = handlers } // PushBack push a function to the end of the pipeline func (p *pipelineChannel) PushBack(h Func) { p.mu.Lock() defer p.mu.Unlock() p.handlers = append(p.handlers, h) } // Process message with all pipeline functions func (p *pipelineChannel) Process(s *session.Session, msg *message.Message) error { p.mu.RLock() defer p.mu.RUnlock() if len(p.handlers) < 1 { return nil } for _, h := range p.handlers { err := h(s, msg) if err != nil { return err } } return nil }