smallstep-certificates/autocert/controller/client.go
2019-02-11 20:27:41 -08:00

116 lines
2.9 KiB
Go

package main
import (
"crypto/tls"
"crypto/x509"
"fmt"
"io/ioutil"
"net"
"net/http"
"os"
"strings"
"time"
)
const (
serviceAccountToken = "/var/run/secrets/kubernetes.io/serviceaccount/token"
serviceAccountCACert = "/var/run/secrets/kubernetes.io/serviceaccount/ca.crt"
)
// Client is minimal kubernetes client interface
type Client interface {
Do(req *http.Request) (*http.Response, error)
GetRequest(url string) (*http.Request, error)
PostRequest(url, body, contentType string) (*http.Request, error)
DeleteRequest(url string) (*http.Request, error)
Host() string
}
type k8sClient struct {
host string
token string
httpClient *http.Client
}
func (kc *k8sClient) GetRequest(url string) (*http.Request, error) {
if !strings.HasPrefix(url, kc.host) {
url = fmt.Sprintf("%s/%s", kc.host, url)
}
req, err := http.NewRequest("GET", url, nil)
if err != nil {
return nil, err
}
if len(kc.token) > 0 {
req.Header.Set("Authorization", "Bearer "+kc.token)
}
return req, nil
}
func (kc *k8sClient) PostRequest(url string, body string, contentType string) (*http.Request, error) {
if !strings.HasPrefix(url, kc.host) {
url = fmt.Sprintf("%s/%s", kc.host, url)
}
req, err := http.NewRequest("POST", url, strings.NewReader(body))
if err != nil {
return nil, err
}
if len(kc.token) > 0 {
req.Header.Set("Authorization", "Bearer "+kc.token)
}
if contentType != "" {
req.Header.Set("Content-Type", contentType)
}
return req, nil
}
func (kc *k8sClient) DeleteRequest(url string) (*http.Request, error) {
if !strings.HasPrefix(url, kc.host) {
url = fmt.Sprintf("%s/%s", kc.host, url)
}
req, err := http.NewRequest("DELETE", url, nil)
if err != nil {
return nil, err
}
if len(kc.token) > 0 {
req.Header.Set("Authorization", "Bearer "+kc.token)
}
return req, nil
}
func (kc *k8sClient) Do(req *http.Request) (*http.Response, error) {
return kc.httpClient.Do(req)
}
func (kc *k8sClient) Host() string {
return kc.host
}
// NewInClusterK8sClient creates K8sClient if it is inside Kubernetes
func NewInClusterK8sClient() (Client, error) {
host, port := os.Getenv("KUBERNETES_SERVICE_HOST"), os.Getenv("KUBERNETES_SERVICE_PORT")
if len(host) == 0 || len(port) == 0 {
return nil, fmt.Errorf("unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined")
}
token, err := ioutil.ReadFile(serviceAccountToken)
if err != nil {
return nil, err
}
ca, err := ioutil.ReadFile(serviceAccountCACert)
if err != nil {
return nil, err
}
certPool := x509.NewCertPool()
certPool.AppendCertsFromPEM(ca)
transport := &http.Transport{TLSClientConfig: &tls.Config{
MinVersion: tls.VersionTLS10,
RootCAs: certPool,
}}
httpClient := &http.Client{Transport: transport, Timeout: time.Nanosecond * 0}
return &k8sClient{
host: "https://" + net.JoinHostPort(host, port),
token: string(token),
httpClient: httpClient,
}, nil
}