英文:
How can I source a shell script using Go?
问题
我想使用Go语言来源码shell脚本。理想情况下，使用以下代码：
cmd := exec.Command("/bin/bash", "source", file.Name())
但是，我知道"source"是一个bash内置函数，而不是一个可执行文件。
然而，我在Python中找到了一些模拟这种行为的方法：
http://pythonwise.blogspot.fr/2010/04/sourcing-shell-script.html
不幸的是，我不知道如何在Go语言中实现这个。有人有主意吗？
谢谢！
英文:
I want to source shell scripts using Go. Ideally the following code
cmd := exec.Command("/bin/bash", "source", file.Name())
but, I know that "source" is a bash built-in function, not an executable.
However, I have found some ways to mimic this behavior in Python:
http://pythonwise.blogspot.fr/2010/04/sourcing-shell-script.html
Unfortunately, I don't know how to translate this in Go. Does anyone have an idea ?
Thanks !
答案1
得分: 9
在运行程序时，可以使用exec设置环境变量：
cmd := exec.Command("whatever")
cmd.Env = []string{"A=B"}
cmd.Run()
如果你真的需要源代码，可以通过bash运行命令：
cmd := exec.Command("bash", "-c", "source " + file.Name() + " ; echo 'hi'")
cmd.Run()
可以使用这个库进行更全面的工作流程：https://github.com/progrium/go-basher。
更新：这里有一个修改当前环境的示例：
package main
import (
"bufio"
"bytes"
"io/ioutil"
"log"
"os"
"os/exec"
"strings"
)
func main() {
err := ioutil.WriteFile("example_source", []byte("export FOO=bar; echo $FOO"), 0777)
if err != nil {
log.Fatal(err)
}
cmd := exec.Command("bash", "-c", "source example_source ; echo '<<<ENVIRONMENT>>>' ; env")
bs, err := cmd.CombinedOutput()
if err != nil {
log.Fatalln(err)
}
s := bufio.NewScanner(bytes.NewReader(bs))
start := false
for s.Scan() {
if s.Text() == "<<<ENVIRONMENT>>>" {
start = true
} else if start {
kv := strings.SplitN(s.Text(), "=", 2)
if len(kv) == 2 {
os.Setenv(kv[0], kv[1])
}
}
}
}
log.Println(os.Getenv("FOO"))
英文:
You can set environmental variables when running a program using exec:
cmd := exec.Command("whatever")
cmd.Env = []string{"A=B"}
cmd.Run()
If you really need source then you can run your command through bash:
cmd := exec.Command("bash", "-c", "source " + file.Name() + " ; echo 'hi'")
cmd.Run()
Check out this library for a more full-featured workflow: https://github.com/progrium/go-basher.
Update: Here's an example that modifies the current environment:
package main
import (
"bufio"
"bytes"
"io/ioutil"
"log"
"os"
"os/exec"
"strings"
)
func main() {
err := ioutil.WriteFile("example_source", []byte("export FOO=bar; echo $FOO"), 0777)
if err != nil {
log.Fatal(err)
}
cmd := exec.Command("bash", "-c", "source example_source ; echo '<<<ENVIRONMENT>>>' ; env")
bs, err := cmd.CombinedOutput()
if err != nil {
log.Fatalln(err)
}
s := bufio.NewScanner(bytes.NewReader(bs))
start := false
for s.Scan() {
if s.Text() == "<<<ENVIRONMENT>>>" {
start = true
} else if start {
kv := strings.SplitN(s.Text(), "=", 2)
if len(kv) == 2 {
os.Setenv(kv[0], kv[1])
}
}
}
}
log.Println(os.Getenv("FOO"))
答案2
得分: 3
我最近在我的shell/bash Golang库中添加了一个这样的实用函数：
https://godoc.org/mvdan.cc/sh/shell#SourceFile
例如，你可以这样做：
vars, err := shell.SourceFile("foo.sh")
if err != nil { ... }
fmt.Println(vars["URL"].Value)
// http://the.url/value
这个函数相当安全，因为它实际上不会调用bash或任何其他程序。它会解析shell脚本，然后解释执行。但在解释执行时，它有一个白名单，规定了脚本可以打开哪些文件和执行哪些程序。
解释器还有一个context.Context，所以如果你想要防止无限循环或其他糟糕的代码，你可以设置一个超时时间。
英文:
I have recently added such a utility function to my shell/bash Golang library:
https://godoc.org/mvdan.cc/sh/shell#SourceFile
For example, you could do:
vars, err := shell.SourceFile("foo.sh")
if err != nil { ... }
fmt.Println(vars["URL"].Value)
// http://the.url/value
It's decently safe, because it never actually calls bash nor any other program. It parses the shell script, then interprets it. But when interpreting, it has a whitelist of what files the script can open and what programs the script can execute.
The interpreter also has a context.Context, so you can set a timeout if you want to be protected against forever loops or other bad code.
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论