traefik/vendor/github.com/docker/docker-credential-helpers/credentials/credentials.go
2018-01-22 12:16:03 +01:00

186 lines
4.6 KiB
Go

package credentials
import (
"bufio"
"bytes"
"encoding/json"
"fmt"
"io"
"os"
"strings"
)
// Credentials holds the information shared between docker and the credentials store.
type Credentials struct {
ServerURL string
Username string
Secret string
}
// isValid checks the integrity of Credentials object such that no credentials lack
// a server URL or a username.
// It returns whether the credentials are valid and the error if it isn't.
// error values can be errCredentialsMissingServerURL or errCredentialsMissingUsername
func (c *Credentials) isValid() (bool, error) {
if len(c.ServerURL) == 0 {
return false, NewErrCredentialsMissingServerURL()
}
if len(c.Username) == 0 {
return false, NewErrCredentialsMissingUsername()
}
return true, nil
}
// CredsLabel holds the way Docker credentials should be labeled as such in credentials stores that allow labelling.
// That label allows to filter out non-Docker credentials too at lookup/search in macOS keychain,
// Windows credentials manager and Linux libsecret. Default value is "Docker Credentials"
var CredsLabel = "Docker Credentials"
// SetCredsLabel is a simple setter for CredsLabel
func SetCredsLabel(label string) {
CredsLabel = label
}
// Serve initializes the credentials helper and parses the action argument.
// This function is designed to be called from a command line interface.
// It uses os.Args[1] as the key for the action.
// It uses os.Stdin as input and os.Stdout as output.
// This function terminates the program with os.Exit(1) if there is an error.
func Serve(helper Helper) {
var err error
if len(os.Args) != 2 {
err = fmt.Errorf("Usage: %s <store|get|erase|list|version>", os.Args[0])
}
if err == nil {
err = HandleCommand(helper, os.Args[1], os.Stdin, os.Stdout)
}
if err != nil {
fmt.Fprintf(os.Stdout, "%v\n", err)
os.Exit(1)
}
}
// HandleCommand uses a helper and a key to run a credential action.
func HandleCommand(helper Helper, key string, in io.Reader, out io.Writer) error {
switch key {
case "store":
return Store(helper, in)
case "get":
return Get(helper, in, out)
case "erase":
return Erase(helper, in)
case "list":
return List(helper, out)
case "version":
return PrintVersion(out)
}
return fmt.Errorf("Unknown credential action `%s`", key)
}
// Store uses a helper and an input reader to save credentials.
// The reader must contain the JSON serialization of a Credentials struct.
func Store(helper Helper, reader io.Reader) error {
scanner := bufio.NewScanner(reader)
buffer := new(bytes.Buffer)
for scanner.Scan() {
buffer.Write(scanner.Bytes())
}
if err := scanner.Err(); err != nil && err != io.EOF {
return err
}
var creds Credentials
if err := json.NewDecoder(buffer).Decode(&creds); err != nil {
return err
}
if ok, err := creds.isValid(); !ok {
return err
}
return helper.Add(&creds)
}
// Get retrieves the credentials for a given server url.
// The reader must contain the server URL to search.
// The writer is used to write the JSON serialization of the credentials.
func Get(helper Helper, reader io.Reader, writer io.Writer) error {
scanner := bufio.NewScanner(reader)
buffer := new(bytes.Buffer)
for scanner.Scan() {
buffer.Write(scanner.Bytes())
}
if err := scanner.Err(); err != nil && err != io.EOF {
return err
}
serverURL := strings.TrimSpace(buffer.String())
if len(serverURL) == 0 {
return NewErrCredentialsMissingServerURL()
}
username, secret, err := helper.Get(serverURL)
if err != nil {
return err
}
resp := Credentials{
ServerURL: serverURL,
Username: username,
Secret: secret,
}
buffer.Reset()
if err := json.NewEncoder(buffer).Encode(resp); err != nil {
return err
}
fmt.Fprint(writer, buffer.String())
return nil
}
// Erase removes credentials from the store.
// The reader must contain the server URL to remove.
func Erase(helper Helper, reader io.Reader) error {
scanner := bufio.NewScanner(reader)
buffer := new(bytes.Buffer)
for scanner.Scan() {
buffer.Write(scanner.Bytes())
}
if err := scanner.Err(); err != nil && err != io.EOF {
return err
}
serverURL := strings.TrimSpace(buffer.String())
if len(serverURL) == 0 {
return NewErrCredentialsMissingServerURL()
}
return helper.Delete(serverURL)
}
//List returns all the serverURLs of keys in
//the OS store as a list of strings
func List(helper Helper, writer io.Writer) error {
accts, err := helper.List()
if err != nil {
return err
}
return json.NewEncoder(writer).Encode(accts)
}
//PrintVersion outputs the current version.
func PrintVersion(writer io.Writer) error {
fmt.Fprintln(writer, Version)
return nil
}