dictionary - 嵌套字典 Golang 的麻烦

Question

去代码:

package main

import (
    "bufio"
    _ "bytes"
    "fmt"
    _ "io"
    "log"
    "os"
    "os/user"
    "path/filepath"
    _ "reflect"
    "regexp"
    "runtime"
    "strconv"
    "strings"
    "sync"
    "time"

    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/session"
    "github.com/aws/aws-sdk-go/service/s3"
    "github.com/aws/aws-sdk-go/service/s3/s3manager"
)

var (
    LocalDirectory   = "s3logs" // Into this directory
    Lock             sync.Mutex
    totalImpressions int
)

var data = make(map[string]map[string]int)

func main() {
    start := time.Now()
    // by adding this line i'm telling the program to run the threads on 4 different cores at the same time, Parallelism!!
    //REMEMBER TO ADD BLOCKS TO STOP RACE CONDITIONS
    runtime.GOMAXPROCS(4)
    var wg sync.WaitGroup

    var year, month, day = time.Now().Date()
    str_year := strconv.Itoa(year)
    str_month := strconv.Itoa(int(month))
    str_day := strconv.Itoa(day)

    if int(month) < 10 {
        str_month = "0" + strconv.Itoa(int(month))
    }
    if day < 10 {
        str_day = "0" + strconv.Itoa(day)
    }

    regBuckets := map[string]string{
        "us-west-1": "pubgears-ca",
        "test":      "test",
    }

    for region, bucket := range regBuckets {
        prefix := fmt.Sprintf("tagserver/logs/AWSLogs/978380792767/elasticloadbalancing/%s/%s/%s/%s/", region, str_year, str_month, str_day)
        wg.Add(1)
        go getLogs(region, bucket, LocalDirectory+bucket, &prefix, &wg)
    }
    wg.Wait()

    //salon/t1/728x90/index
    //totalImpressions := 0
    // var provider = make(map[string]int)
    // for key, value := range data {
    //   key = strings.TrimSpace(key)
    //   pro := strings.Split(key, "_")[3]
    //
    //   if strings.Contains(pro, "pp") == true || (pro == "pulsepoint") || (pro == "cweb") {
    //     provider["pulsepoint"] += value
    //   } else if (pro == "openx") || (pro == "openx3") {
    //     provider["openx"] += value
    //   } else if key == " " {
    //     continue
    //   } else {
    //     provider[pro] += value
    //   }
    //   totalImpressions += value
    // }

    for tag, value := range data {
        for hour, imp := range value {
            fmt.Printf("tag: %s  \n hour: %s impression %s\n", tag, hour, imp)
        }
    }

    //sl = sl[:len(sl)-1]

    elapsed := time.Since(start)
    fmt.Printf("\nTime took %s\n", elapsed)

}

func getLogs(region string, bucket string, directory string, prefix *string, wg *sync.WaitGroup) {
    sess := session.New()
    client := s3.New(sess, &aws.Config{Region: aws.String(region)})

    params := &s3.ListObjectsInput{Bucket: &bucket, Prefix: prefix}
    manager := s3manager.NewDownloaderWithClient(client, func(d *s3manager.Downloader) {
        d.PartSize = 5 * 1024 * 1024 // 6MB per part
        d.Concurrency = 4
    })
    d := downloader{bucket: bucket, dir: directory, Downloader: manager}
    client.ListObjectsPages(params, d.eachPage)
    wg.Done()
}

// downloader object and methods
type downloader struct {
    *s3manager.Downloader
    bucket, dir string
}

func (d *downloader) eachPage(page *s3.ListObjectsOutput, more bool) bool {
    for _, obj := range page.Contents {
        // fmt.Println(obj)
        //     return true
        d.downloadToFile(*obj.Key)
    }
    return true
}

func (d *downloader) downloadToFile(key string) {
    // Create the directories in the path
    // desktop path
    user, errs := user.Current()
    if errs != nil {
        panic(errs)
    }
    homedir := user.HomeDir
    desktop := homedir + "/Desktop/" + d.dir
    file := filepath.Join(desktop, key)
    if err := os.MkdirAll(filepath.Dir(file), 0775); err != nil {
        panic(err)
    }

    // Setup the local file
    fd, err := os.Create(file)
    if err != nil {
        panic(err)
    }
    defer fd.Close()

    // Download the file using the AWS SDK
    //fmt.Printf("Downloading s3://%s/%s to %s...\n", d.bucket, key, file)
    params := &s3.GetObjectInput{Bucket: &d.bucket, Key: &key}
    d.Download(fd, params)
    _, e := d.Download(fd, params)
    if e != nil {
        panic(e)
    }

    f, err := os.Open(file)
    if err != nil {
        log.Fatal(err)
    }
    defer f.Close()

    tag := regexp.MustCompile("/([a-zA-Z0-9_]+/{1}[a-zA-Z0-9_]+/{1}[a-zA-Z0-9_]+/{1}[a-zA-Z0-9_]+)")
    date := regexp.MustCompile("T([^:]+)")
    scanner := bufio.NewScanner(f)

    // HAVING TROUBLE HERE
    for scanner.Scan() {
        //dateCollection := make(map[string]int)
        m := tag.FindString(scanner.Text())
        if m != "" {
            // stop races
            Lock.Lock()
            arr := strings.Split(m, "/")
            taghash := strings.Join(arr, "_")
            taghash = strings.TrimLeft(taghash, "_")
            //data[taghash]++
            m = date.FindString(scanner.Text())
            if m != "" {
                hour := m
                data[taghash] = make(map[string]int)
                data[taghash][hour]++
            }
            Lock.Unlock()
        }
    }
    fmt.Println(file)
    os.Remove(file)
    if err := scanner.Err(); err != nil {
        log.Fatal(err)
    }
}

我遇到问题的区域从下面第 167 行部分开始:

for scanner.Scan() {
        //dateCollection := make(map[string]int)
        m := tag.FindString(scanner.Text())
        if m != "" {
            // stop races
            Lock.Lock()
            arr := strings.Split(m, "/")
            taghash := strings.Join(arr, "_")
            taghash = strings.TrimLeft(taghash, "_")
            //data[taghash]++
            m = date.FindString(scanner.Text())
            if m != "" {
                hour := m
                data[taghash] = make(map[string]int)
                data[taghash][hour]++
            }
            Lock.Unlock()
        }
    }
    fmt.Println(file)
    os.Remove(file)
    if err := scanner.Err(); err != nil {
        log.Fatal(err)
    }

当我在主函数中打印值时得到的输出

fstvt1_ros_300x600_pp8_1 T07 1

我期待一个看起来像这样的输出:

fstvt1_ros_300x600_pp8_1
T00 213434
T01 23432
T02 3324
T03 324
T04 324
T05 0 ...
(this isn't real data)

我想做什么:我有一个数据映射 var data = make(map[string]map[string]int) 其键等于 taghash，例如fstvt1_ros_300x600_pp8_1。该值是数据映射。该映射的键值应该是一个字符串和一个整数。我想要多张 map 。每个键一个... T01，T02 .. 当前输出的是我正在迭代的最后一项中的最后一项，而不是每个标签哈希的键和值的集合。我该怎么做，而不是覆盖数据，它会添加新的键值 T01、T02.. 如果标签哈希和小时是增加该特定对象的一些。

我目前使用的代码行:

T01, T02..

data[taghash][hour]++

如果 taghash 和 hour 存在，那么它应该递增。如果标签哈希和小时不存在，则创建标签哈希并添加新 key 和增量。

Answer 1

错误来自

data[taghash] = make(map[string]int)

每次都将 data[taghash] 设置为新分配的映射。那绝对不是你想要做的。相反:

if _, ok := data[taghash]; !ok {
    // data[taghash] does not exist -- create it!
    data[taghash] := make(map[string]int)
}
data[taghash][hour]++

这相当于:

# Python
data.setdefault(taghash, {}).setdefault(hour, 0) += 1

或者

if taghash not in data:
    data[taghash] = {}
if hour not in data[taghash]:
    data[taghash][hour] = 1
else:
    data[taghash][hour] += 1