要点

计算字符串或码流的SHA1: sha1.Sum()

示例代码

util.go

package main

import (
    "fmt"
    "crypto/sha1"
    "io/ioutil"
)

/*
Get the sha1 of file's content.

If success, return the sha1 hex string.
If fail, return "".
*/
func GetFileSHA1(filename string) string {
    data, err := ioutil.ReadFile(filename)
    if err != nil {
        fmt.Println("sum error: ", err)
        return ""
    }

    b := sha1.Sum(data)
    return fmt.Sprintf("%X", b)    
}

main.go

package main

import (
    "fmt"
    "io/ioutil"
    "os"
)


func main() {
    temp_file_name := "xyzabcdefghijklmnxyz.xyz"
    content := []byte("Hello, Go Programming Language!")

    err := ioutil.WriteFile(temp_file_name, content, 0666) 
    if err != nil {
        fmt.Println(err)
        return
    }

    sha1 := GetFileSHA1(temp_file_name)
    fmt.Println(sha1)

    os.Remove(temp_file_name)
}

运行

$ go run main.go util.go 
C6ADC2F32EF2455EE0A7F66A874431B20043384F
$

相关命令 shasum & openssl sha1

$ echo -n Hello, Go Programming Language! > xyzabcdefghijklmnxyz.xyz
$ shasum xyzabcdefghijklmnxyz.xyz 
c6adc2f32ef2455ee0a7f66a874431b20043384f  xyzabcdefghijklmnxyz.xyz
$ openssl sha1 xyzabcdefghijklmnxyz.xyz 
SHA1(xyzabcdefghijklmnxyz.xyz)= c6adc2f32ef2455ee0a7f66a874431b20043384f
$