cmdr

cmdr (pronounced “commander”) is a go package to abstract and simplify execution of commands on the operation system.

how to use it

First things first:

go get -u -v go get github.com/sebastianwebber/cmdr

Basically create a Command and call the Run function. Take a look:

package main
import (
    "fmt"
    "github.com/sebastianwebber/cmdr"
)
func main() {
    // *** short version ***********
    out, err := cmdr.New(true, "ls", "-lh", "~/tmp2/*").Run()
    fmt.Println("Output:", string(out))
    if err != nil {
        fmt.Println("OOPS:", err.Error())
    }
    // *** verbose version ***********
    // New is a helper to create a Command
    // You can call it by a shell like bash if you want (useful to process expressions like *)
    cmd := cmdr.New(true, "ls", "-lh", "~/tmp/*")
    // You can declare the variable as well:
    // cmd := cmdr.Command{  }
    // You can also parse a command into a Command:
    // cmd := cmdr.Parse(`psql -At -c 'select now();'`)
    // Enable timeout if you want (5s by example)
    cmd.Options.Timeout = 5
    // To check if the inputed command is valid, use the IsValid function.
    // It checks if the command exists in PATH
    if cmd.IsValid() {
        // To execute the command, just call the Run function
        out, err := cmd.Run()
        if err != nil {
            panic(err)
        }
        // here comes the output
        fmt.Println(string(out))
    }
}

Grouping commands

Its possible to group a list of commands:

package main
import (
    "fmt"
    "github.com/sebastianwebber/cmdr"
)
func main() {
    // Group options (experimental)
    total, err := cmdr.Group(
        cmdr.AbortOnError,
        cmdr.New(false, "ls", "-lh"),
        cmdr.New(false, "pwd 123q6236"),
        cmdr.New(false, "cat", "/etc/hosts"),
    )
    fmt.Printf("%d commands executed without error. \n", total)
    if err != nil {
        fmt.Printf("Houston, we have a problem! %v\n", err)
    }
}

This is a work in progress.

TODO List

• Add option to timeout
• Enable way to group commands
• Print output of each command in the group (perhaps adding a name option?)
• Pipe support
• add support por multiple commands

License