open-nomad/client/driver/args/args.go

38 lines
970 B
Go

package args
import "regexp"
var (
envRe = regexp.MustCompile(`\$({[a-zA-Z0-9_]+}|[a-zA-Z0-9_]+)`)
)
// ParseAndReplace takes the user supplied args and a map of environment
// variables. It replaces any instance of an environment variable in the args
// with the actual value.
func ParseAndReplace(args []string, env map[string]string) []string {
replaced := make([]string, len(args))
for i, arg := range args {
replaced[i] = ReplaceEnv(arg, env)
}
return replaced
}
// ReplaceEnv takes an arg and replaces all occurences of environment variables.
// If the variable is found in the passed map it is replaced, otherwise the
// original string is returned.
func ReplaceEnv(arg string, env map[string]string) string {
return envRe.ReplaceAllStringFunc(arg, func(arg string) string {
stripped := arg[1:]
if stripped[0] == '{' {
stripped = stripped[1 : len(stripped)-1]
}
if value, ok := env[stripped]; ok {
return value
}
return arg
})
}