go - 有什么更好的方法来实现在社交网络中验证和执行帖子的例程？

Question

我正在编写一个小型应用程序来在社交网络上执行自动发布。

我的意图是用户可以通过网络界面在特定时间创建帖子，机器人可以检查安排的新帖子并执行它们。

我在 Go 上处理例程和频道时遇到问题。

我将在下面留下一个反映我的代码实际情况的示例。它包含一些注释以使其更易于理解。

实施随时检查新帖子的例程的最佳方法是什么？ 记住：

1. 用户可以随时输入新帖子。
2. 该机器人可以同时管理数百/数千个帐户。尽可能少地消耗处理是必不可少的。

play.golang.org（这里）

    package main

    import (
        "fmt"
        "sync"
        "time"
    )

    var botRunning = true
    var wg = &sync.WaitGroup{}

    func main() {
        // I start the routine of checking for and posting scheduled appointments.
        wg.Add(1)
        go postingScheduled()

        // Later the user passes the command to stop the post.
        // At that moment I would like to stop the routine immediately without getting stuck in a loop.
        // What is the best way to do this?
        time.Sleep(3 * time.Second)
        botRunning = false

        // ignore down
        time.Sleep(2 * time.Second)
        panic("")

        wg.Wait()
    }

    // Function that keeps checking whether the routine should continue or not.
    // Check every 2 seconds.
    // I think this is very wrong because it consumes unnecessary resources.
    // -> Is there another way to do this?
    func checkRunning() {
        for {
            fmt.Println("Pause/Running? - ", botRunning)
            if botRunning {
                break
            }
            time.Sleep(2 * time.Second)
        }
    }

    // Routine that looks for the scheduled posts in the database.
    // It inserts the date of the posts in the Ticker and when the time comes the posting takes place.
    // This application will have hundreds of social network accounts and each will have its own function running in parallel.
    // -> What better way to check constantly if there are scheduled items in the database consuming the least resources on the machine?
    // -> Another important question. User can schedule posts to the database at any time. How do I check for new posts schedule while the Ticker is waiting for the time the last posting loaded?
    func postingScheduled() {
        fmt.Println("Init bot posting routine")
        defer wg.Done()
        for {
            checkRunning()
            <-time.NewTicker(2 * time.Second).C
            fmt.Println("posted success")
        }

    }

标签： gochannelroutines

Answer 1

有了彼得的回应，我能够适应所有需要来制作草图。

我不知道这是否是最好的方法，也许某些功能会不必要地消耗处理资源。如果有人对重构有更好的想法，我将非常感激。

    package main

    import (
        "fmt"
        "log"
        "net/http"
        "sort"
        "time"
    )

    type posting struct {
        caption string
        scheduledTo time.Time
    }

    const dateLayoutFormat  = "02-01-2006 15:04:05"

    var botStatus = true
    var indexPosting int
    var tickerSchedule = time.NewTicker(1)
    var posts = []posting{
        {caption: "item 1", scheduledTo: time.Now().Add(5 * time.Second)},
        {caption: "item 2", scheduledTo: time.Now().Add(25 * time.Second)},
    }

    func init() {
        indexPosting = len(posts)
    }

    func main() {
        http.HandleFunc("/", func (w http.ResponseWriter, r *http.Request) {
            fmt.Fprint(w, "Bem vindo ao bot")
        })

        http.HandleFunc("/stop", func (w http.ResponseWriter, r *http.Request) {
            fmt.Fprint(w, "Parando o bot!")
            stopBot()
        })

        http.HandleFunc("/start", func (w http.ResponseWriter, r *http.Request) {
            fmt.Fprint(w, "Iniciando o bot!")
            startBot()
        })

        http.HandleFunc("/add", func (w http.ResponseWriter, r *http.Request) {
            t := time.Now().Add(5 * time.Second)
            indexPosting++

            addItemDB(posting{
                caption: fmt.Sprint("item ", indexPosting),
                scheduledTo: t,
            })

            fmt.Fprint(w, "Adicionando nova postagem \nPróximo post será: ", t.Format(dateLayoutFormat))
        })

        if botStatus {
            go workerScheduled()
        }

        log.Print("Inicnando server...")
        if err := http.ListenAndServe(":9090", nil); err != nil {
            log.Print("erro ao iniciar servidor => ", err)
        }

    }

    func workerScheduled() {
        for {
            log.Print("listando as próximas postagens")

            pts := getNextPostsDB()
            if len(pts) == 0 {
                log.Print("sem postagem agendada")
                botStatus = false
                return
            }

            p1 := pts[0]

            log.Printf("Próxima postagem será: %s \n\n", string(p1.scheduledTo.Format(dateLayoutFormat)))
            <- updateTimer(p1.scheduledTo).C

            if !botStatus {
                log.Print("postagem cancelado, bot status = parado")
                return
            }

            if time.Until(p1.scheduledTo) > 1 * time.Second {
                updateTimer(p1.scheduledTo)
                log.Print("timer resetado")
                continue
            }

            post(p1)
            if len(pts) > 1 {
                p2 := pts[1]
                updateTimer(p2.scheduledTo)
            }
            updatePostedDB()
        }
    }

    func updateTimer(t time.Time) *time.Ticker {
        tickerSchedule = time.NewTicker(t.Sub(time.Now()))
        return tickerSchedule
    }

    func post(p posting) {
        log.Printf("'%s' postado com sucesso", p.caption)
    }

    func addItemDB(p posting) {
        posts = append(posts, p)
        if botStatus {
            next := getNextPostDB()
            updateTimer(next.scheduledTo)
        } else {
            botStatus = true
            go workerScheduled()
        }
    }

    func getNextPostDB() posting {
        return getNextPostsDB()[0]
    }

    func getNextPostsDB() []posting {
        orderPostsList()
        removePostExpired()
        return posts
    }

    func removePostExpired() {
        for _, p := range posts {
            if p.scheduledTo.Before(time.Now()) {
                log.Printf("removendo postagem expirada")
                removePostByIndex(getIndexOf(p))
            }
        }
    }

    func removePostByIndex(i int) {
        copy(posts[i:], posts[i+1:])
        posts = posts[:len(posts)-1]
    }

    func getIndexOf(post posting) int {
        for i, p := range posts {
            if p.caption == post.caption {
                return i
            }
        }
        return -1
    }

    func updatePostedDB() {
        removePostByIndex(0)
    }

    func orderPostsList() {
        sort.Slice(posts, func(i, j int) bool {
            return posts[i].scheduledTo.Before(posts[j].scheduledTo)
        })
    }

    func startBot() {
        if !botStatus {
            log.Printf("comando 'iniciar bot'")
            botStatus = true
            go workerScheduled()
        } else {
            log.Printf("comando 'iniciar bot' (já iniciado)")
        }
    }

    func stopBot() {
        if botStatus {
            log.Printf("comando 'pausar bot'")
            botStatus = false
            tickerSchedule.Stop()
        } else {
            log.Printf("comando 'pausar bot' (já pausado)")
        }
    }