traefik/pkg/plugins/client.go
2020-07-15 20:14:04 +02:00

415 lines
9 KiB
Go

package plugins
import (
zipa "archive/zip"
"context"
"crypto/sha256"
"encoding/json"
"errors"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"os"
"path"
"path/filepath"
"strings"
"time"
"golang.org/x/mod/module"
"golang.org/x/mod/zip"
"gopkg.in/yaml.v3"
)
const (
sourcesFolder = "sources"
archivesFolder = "archives"
stateFilename = "state.json"
goPathSrc = "src"
pluginManifest = ".traefik.yml"
)
const pilotURL = "https://plugin.pilot.traefik.io/public/"
const (
hashHeader = "X-Plugin-Hash"
tokenHeader = "X-Token"
)
// ClientOptions the options of a Traefik Pilot client.
type ClientOptions struct {
Output string
Token string
}
// Client a Traefik Pilot client.
type Client struct {
HTTPClient *http.Client
baseURL *url.URL
token string
archives string
stateFile string
goPath string
sources string
}
// NewClient creates a new Traefik Pilot client.
func NewClient(opts ClientOptions) (*Client, error) {
baseURL, err := url.Parse(pilotURL)
if err != nil {
return nil, err
}
sourcesRootPath := filepath.Join(filepath.FromSlash(opts.Output), sourcesFolder)
err = resetDirectory(sourcesRootPath)
if err != nil {
return nil, err
}
goPath, err := ioutil.TempDir(sourcesRootPath, "gop-*")
if err != nil {
return nil, fmt.Errorf("failed to create GoPath: %w", err)
}
archivesPath := filepath.Join(filepath.FromSlash(opts.Output), archivesFolder)
err = os.MkdirAll(archivesPath, 0o755)
if err != nil {
return nil, fmt.Errorf("failed to create archives directory %s: %w", archivesPath, err)
}
return &Client{
HTTPClient: &http.Client{Timeout: 5 * time.Second},
baseURL: baseURL,
archives: archivesPath,
stateFile: filepath.Join(archivesPath, stateFilename),
goPath: goPath,
sources: filepath.Join(goPath, goPathSrc),
token: opts.Token,
}, nil
}
// GoPath gets the plugins GoPath.
func (c *Client) GoPath() string {
return c.goPath
}
// ReadManifest reads a plugin manifest.
func (c *Client) ReadManifest(moduleName string) (*Manifest, error) {
return ReadManifest(c.goPath, moduleName)
}
// ReadManifest reads a plugin manifest.
func ReadManifest(goPath, moduleName string) (*Manifest, error) {
p := filepath.Join(goPath, goPathSrc, filepath.FromSlash(moduleName), pluginManifest)
file, err := os.Open(p)
if err != nil {
return nil, fmt.Errorf("failed to open the plugin manifest %s: %w", p, err)
}
defer func() { _ = file.Close() }()
m := &Manifest{}
err = yaml.NewDecoder(file).Decode(m)
if err != nil {
return nil, fmt.Errorf("failed to decode the plugin manifest %s: %w", p, err)
}
return m, nil
}
// Download downloads a plugin archive.
func (c *Client) Download(ctx context.Context, pName, pVersion string) (string, error) {
filename := c.buildArchivePath(pName, pVersion)
var hash string
_, err := os.Stat(filename)
if err != nil && !os.IsNotExist(err) {
return "", fmt.Errorf("failed to read archive %s: %w", filename, err)
}
if err == nil {
hash, err = computeHash(filename)
if err != nil {
return "", fmt.Errorf("failed to compute hash: %w", err)
}
}
endpoint, err := c.baseURL.Parse(path.Join(c.baseURL.Path, "download", pName, pVersion))
if err != nil {
return "", fmt.Errorf("failed to parse endpoint URL: %w", err)
}
req, err := http.NewRequestWithContext(ctx, http.MethodGet, endpoint.String(), nil)
if err != nil {
return "", fmt.Errorf("failed to create request: %w", err)
}
if hash != "" {
req.Header.Set(hashHeader, hash)
}
if c.token != "" {
req.Header.Set(tokenHeader, c.token)
}
resp, err := c.HTTPClient.Do(req)
if err != nil {
return "", fmt.Errorf("failed to call service: %w", err)
}
defer func() { _ = resp.Body.Close() }()
if resp.StatusCode == http.StatusOK {
err = os.MkdirAll(filepath.Dir(filename), 0o755)
if err != nil {
return "", fmt.Errorf("failed to create directory: %w", err)
}
var file *os.File
file, err = os.Create(filename)
if err != nil {
return "", fmt.Errorf("failed to create file %q: %w", filename, err)
}
defer func() { _ = file.Close() }()
_, err = io.Copy(file, resp.Body)
if err != nil {
return "", fmt.Errorf("failed to write response: %w", err)
}
hash, err = computeHash(filename)
if err != nil {
return "", fmt.Errorf("failed to compute hash: %w", err)
}
return hash, nil
}
if resp.StatusCode == http.StatusNotModified {
// noop
return hash, nil
}
data, _ := ioutil.ReadAll(resp.Body)
return "", fmt.Errorf("error: %d: %s", resp.StatusCode, string(data))
}
// Check checks the plugin archive integrity.
func (c *Client) Check(ctx context.Context, pName, pVersion, hash string) error {
endpoint, err := c.baseURL.Parse(path.Join(c.baseURL.Path, "validate", pName, pVersion))
if err != nil {
return fmt.Errorf("failed to parse endpoint URL: %w", err)
}
req, err := http.NewRequestWithContext(ctx, http.MethodGet, endpoint.String(), nil)
if err != nil {
return fmt.Errorf("failed to create request: %w", err)
}
if hash != "" {
req.Header.Set(hashHeader, hash)
}
if c.token != "" {
req.Header.Set(tokenHeader, c.token)
}
resp, err := c.HTTPClient.Do(req)
if err != nil {
return fmt.Errorf("failed to call service: %w", err)
}
defer func() { _ = resp.Body.Close() }()
if resp.StatusCode == http.StatusOK {
return nil
}
return fmt.Errorf("plugin integrity check failed")
}
// Unzip unzip a plugin archive.
func (c *Client) Unzip(pName, pVersion string) error {
err := c.unzipModule(pName, pVersion)
if err == nil {
return nil
}
return c.unzipArchive(pName, pVersion)
}
func (c *Client) unzipModule(pName, pVersion string) error {
src := c.buildArchivePath(pName, pVersion)
dest := filepath.Join(c.sources, filepath.FromSlash(pName))
return zip.Unzip(dest, module.Version{Path: pName, Version: pVersion}, src)
}
func (c *Client) unzipArchive(pName, pVersion string) error {
zipPath := c.buildArchivePath(pName, pVersion)
archive, err := zipa.OpenReader(zipPath)
if err != nil {
return err
}
defer func() { _ = archive.Close() }()
dest := filepath.Join(c.sources, filepath.FromSlash(pName))
for _, f := range archive.File {
err = unzipFile(f, dest)
if err != nil {
return err
}
}
return nil
}
func unzipFile(f *zipa.File, dest string) error {
rc, err := f.Open()
if err != nil {
return err
}
defer func() { _ = rc.Close() }()
pathParts := strings.SplitN(f.Name, string(os.PathSeparator), 2)
p := filepath.Join(dest, pathParts[1])
if f.FileInfo().IsDir() {
return os.MkdirAll(p, f.Mode())
}
err = os.MkdirAll(filepath.Dir(p), 0o750)
if err != nil {
return err
}
elt, err := os.OpenFile(p, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
if err != nil {
return err
}
defer func() { _ = elt.Close() }()
_, err = io.Copy(elt, rc)
if err != nil {
return err
}
return nil
}
// CleanArchives cleans plugins archives.
func (c *Client) CleanArchives(plugins map[string]Descriptor) error {
if _, err := os.Stat(c.stateFile); os.IsNotExist(err) {
return nil
}
stateFile, err := os.Open(c.stateFile)
if err != nil {
return fmt.Errorf("failed to open state file %s: %w", c.stateFile, err)
}
previous := make(map[string]string)
err = json.NewDecoder(stateFile).Decode(&previous)
if err != nil {
return fmt.Errorf("failed to decode state file %s: %w", c.stateFile, err)
}
for pName, pVersion := range previous {
for _, desc := range plugins {
if desc.ModuleName == pName && desc.Version != pVersion {
archivePath := c.buildArchivePath(pName, pVersion)
if err = os.RemoveAll(archivePath); err != nil {
return fmt.Errorf("failed to remove archive %s: %w", archivePath, err)
}
}
}
}
return nil
}
// WriteState writes the plugins state files.
func (c *Client) WriteState(plugins map[string]Descriptor) error {
m := make(map[string]string)
for _, descriptor := range plugins {
m[descriptor.ModuleName] = descriptor.Version
}
mp, err := json.MarshalIndent(m, "", " ")
if err != nil {
return err
}
return ioutil.WriteFile(c.stateFile, mp, 0o600)
}
// ResetAll resets all plugins related directories.
func (c *Client) ResetAll() error {
if c.goPath == "" {
return errors.New("goPath is empty")
}
err := resetDirectory(filepath.Join(c.goPath, ".."))
if err != nil {
return err
}
return resetDirectory(c.archives)
}
func (c *Client) buildArchivePath(pName, pVersion string) string {
return filepath.Join(c.archives, filepath.FromSlash(pName), pVersion+".zip")
}
func resetDirectory(dir string) error {
dirPath, err := filepath.Abs(dir)
if err != nil {
return err
}
currentPath, err := os.Getwd()
if err != nil {
return err
}
if strings.HasPrefix(currentPath, dirPath) {
return fmt.Errorf("cannot be deleted: the directory path %s is the parent of the current path %s", dirPath, currentPath)
}
err = os.RemoveAll(dir)
if err != nil {
return err
}
return os.MkdirAll(dir, 0o755)
}
func computeHash(filepath string) (string, error) {
file, err := os.Open(filepath)
if err != nil {
return "", err
}
hash := sha256.New()
if _, err := io.Copy(hash, file); err != nil {
return "", err
}
sum := hash.Sum(nil)
return fmt.Sprintf("%x", sum), nil
}