Golang で Redis のデータを更新 (Update)

// ----------------------------------------------------------------
//
//  redis_update.go
//
//                  May/21/2018
//
// ----------------------------------------------------------------
package main

import (
    "fmt"
    "net"
    "os"
    "strconv"
    "strings"
    "encoding/json"
    "time"
)

// ----------------------------------------------------------------
func main () {

    fmt.Println ("*** 開始 ***")

    key_in := os.Args[1]
    population_in,_ := strconv.Atoi (os.Args[2])

    fmt.Printf ("id_in = %s\t" , key_in)
    fmt.Printf ("population_in = %d\n" , population_in)

    hostname := "localhost"
    port := "6379"

    conn, err := net.Dial ("tcp",hostname + ":" + port)
    if err != nil {
        fmt.Println(err)
        return
        }

    json_str := mcached_socket_read_proc (conn,key_in)

    if 0 < len (json_str) {
        json_str_new := json_update_proc (json_str,population_in)
        fmt.Println (json_str_new)
        redis_socket_write_proc (conn,key_in,json_str_new)
        }

    conn.Close ()

    fmt.Println ("*** 終了 ***")
}

// ----------------------------------------------------------------
func socket_read_proc (conn net.Conn,key_in string) string {
    str_received := ""
    _, err := conn.Write([]byte("get " + key_in + "\r\n"))
    if err != nil {
        fmt.Println(err)
        return str_received
        }

    buf := make([]byte, 1024)
    nn, err := conn.Read(buf[:])
    if err != nil {
        fmt.Println(err)
        return str_received
        }

    str_received = string(buf[0:nn])

    return  str_received
}

// ----------------------------------------------------------------
func mcached_socket_read_proc (conn net.Conn,key_in string) string {
    json_str := ""
    str_received := socket_read_proc (conn,key_in)

    lines := strings.Split(str_received,"\n")

    if (! strings.Contains(lines[0],"END")) {
        json_str = lines[1]
        }

    return  json_str
}

// ----------------------------------------------------------------
func redis_socket_write_proc (conn net.Conn,key_in string,json_str string) {
    fmt.Println (key_in)
    fmt.Println (json_str)

    comm_aa := "set " + key_in + " '" + json_str + "'\r\n"
    conn.Write([]byte(comm_aa))


    buf := make ([]byte,1024)
    conn.Read (buf[:])

    fmt.Println (string(buf[0:10]))
}

// ----------------------------------------------------------------
func json_update_proc (json_str string,population_in int) string {

    var unit_aa map[string]interface{}
    json.Unmarshal ([]byte(json_str), &unit_aa)
    fmt.Printf ("%s\t",unit_aa["name"])
    fmt.Printf ("%f\t",unit_aa["population"])
    fmt.Printf ("%s\n",unit_aa["date_mod"])

    unit_aa["population"] = population_in
    unit_aa["date_mod"] = get_current_date_proc ()

    output, _ := json.Marshal(unit_aa)

    json_str = string(output)

    return  json_str
}

// ----------------------------------------------------------------
func get_current_date_proc () string {
    now := time.Now ()
    fmt.Printf ("%s\t" ,now)
    fmt.Printf ("%d-%d-%d\n" ,now.Year (),now.Month(),now.Day())
    today := strconv.Itoa (now.Year()) + "-" +
        fmt.Sprintf ("%d",now.Month()) + "-" +
        strconv.Itoa (now.Day())

    return  today
}

// ----------------------------------------------------------------

redis_update: redis_update.go
    go build redis_update.go
clean:
    rm -f redis_update

./redis_update t1854 39412800

$ go version
go version go1.14.2 linux/amd64