cloudinit/datasource/proc_cmdline.go
Lars Wiegman 513a1eb602 Trim newlines from the cloud-config-url kernel parameter and added a test
- In the Fetch function trim whitespace from /proc/cmdline
- New test for Fetch function
- Added Location field to the procCmdline struct for testing
2014-05-21 11:09:39 +02:00

70 lines
1.2 KiB
Go

package datasource
import (
"errors"
"io/ioutil"
"log"
"strings"
)
const (
ProcCmdlineLocation = "/proc/cmdline"
ProcCmdlineCloudConfigFlag = "cloud-config-url"
)
type procCmdline struct{
Location string
}
func NewProcCmdline() *procCmdline {
return &procCmdline{Location: ProcCmdlineLocation}
}
func (self *procCmdline) Fetch() ([]byte, error) {
contents, err := ioutil.ReadFile(self.Location)
if err != nil {
return nil, err
}
cmdline := strings.TrimSpace(string(contents))
url, err := findCloudConfigURL(cmdline)
if err != nil {
return nil, err
}
cfg, err := fetchURL(url)
if err != nil {
return nil, err
}
return cfg, nil
}
func (self *procCmdline) Type() string {
return "proc-cmdline"
}
func findCloudConfigURL(input string) (url string, err error) {
err = errors.New("cloud-config-url not found")
for _, token := range strings.Split(input, " ") {
parts := strings.SplitN(token, "=", 2)
key := parts[0]
key = strings.Replace(key, "_", "-", -1)
if key != "cloud-config-url" {
continue
}
if len(parts) != 2 {
log.Printf("Found cloud-config-url in /proc/cmdline with no value, ignoring.")
continue
}
url = parts[1]
err = nil
}
return
}