traefik/provider/k8s/client.go
emile 720912e880
Add kubernetes Ingress backend
Signed-off-by: Emile Vauge <emile@vauge.com>
2016-04-22 13:57:00 +02:00

163 lines
4.7 KiB
Go

package k8s
import (
"crypto/tls"
"crypto/x509"
"encoding/json"
"fmt"
"github.com/containous/traefik/safe"
"github.com/parnurzeal/gorequest"
"net/http"
"net/url"
"strings"
)
const (
// APIEndpoint defines the base path for kubernetes API resources.
APIEndpoint = "/api/v1"
defaultService = "/namespaces/default/services"
extentionsEndpoint = "/apis/extensions/v1beta1"
defaultIngress = "/ingresses"
)
// Client is a client for the Kubernetes master.
type Client struct {
endpointURL string
tls *tls.Config
token string
caCert []byte
}
// NewClient returns a new Kubernetes client.
// The provided host is an url (scheme://hostname[:port]) of a
// Kubernetes master without any path.
// The provided client is an authorized http.Client used to perform requests to the Kubernetes API master.
func NewClient(baseURL string, caCert []byte, token string) (*Client, error) {
validURL, err := url.Parse(baseURL)
if err != nil {
return nil, fmt.Errorf("failed to parse URL %q: %v", baseURL, err)
}
return &Client{
endpointURL: strings.TrimSuffix(validURL.String(), "/"),
token: token,
caCert: caCert,
}, nil
}
// GetIngresses returns all services in the cluster
func (c *Client) GetIngresses(predicate func(Ingress) bool) ([]Ingress, error) {
getURL := c.endpointURL + extentionsEndpoint + defaultIngress
request := gorequest.New().Get(getURL)
if len(c.token) > 0 {
request.Header["Authorization"] = "Bearer " + c.token
pool := x509.NewCertPool()
pool.AppendCertsFromPEM(c.caCert)
c.tls = &tls.Config{RootCAs: pool}
}
res, body, errs := request.TLSClientConfig(c.tls).EndBytes()
if errs != nil {
return nil, fmt.Errorf("failed to create request: GET %q : %v", getURL, errs)
}
if res.StatusCode != http.StatusOK {
return nil, fmt.Errorf("http error %d GET %q: %q", res.StatusCode, getURL, string(body))
}
var ingressList IngressList
if err := json.Unmarshal(body, &ingressList); err != nil {
return nil, fmt.Errorf("failed to decode list of ingress resources: %v", err)
}
ingresses := ingressList.Items[:0]
for _, ingress := range ingressList.Items {
if predicate(ingress) {
ingresses = append(ingresses, ingress)
}
}
return ingresses, nil
}
// WatchIngresses returns all services in the cluster
func (c *Client) WatchIngresses(predicate func(Ingress) bool, stopCh <-chan bool) (chan interface{}, chan error, error) {
watchCh := make(chan interface{})
errCh := make(chan error)
getURL := c.endpointURL + extentionsEndpoint + defaultIngress + "?watch=true"
// Make request to Kubernetes API
request := gorequest.New().Get(getURL)
if len(c.token) > 0 {
request.Set("Authorization", "Bearer "+c.token)
pool := x509.NewCertPool()
pool.AppendCertsFromPEM(c.caCert)
c.tls = &tls.Config{RootCAs: pool}
}
req, err := request.TLSClientConfig(c.tls).MakeRequest()
if err != nil {
return watchCh, errCh, fmt.Errorf("failed to create request: GET %q : %v", getURL, err)
}
request.Client.Transport = request.Transport
res, err := request.Client.Do(req)
if err != nil {
return watchCh, errCh, fmt.Errorf("failed to make request: GET %q: %v", getURL, err)
}
shouldStop := safe.New(false)
go func() {
select {
case <-stopCh:
shouldStop.Set(true)
res.Body.Close()
return
}
}()
go func() {
defer close(watchCh)
defer close(errCh)
for {
var ingressList interface{}
if err := json.NewDecoder(res.Body).Decode(&ingressList); err != nil {
if !shouldStop.Get().(bool) {
errCh <- fmt.Errorf("failed to decode list of ingress resources: %v", err)
}
return
}
watchCh <- ingressList
}
}()
return watchCh, errCh, nil
}
// GetServices returns all services in the cluster
func (c *Client) GetServices(predicate func(Service) bool) ([]Service, error) {
getURL := c.endpointURL + APIEndpoint + defaultService
// Make request to Kubernetes API
request := gorequest.New().Get(getURL)
if len(c.token) > 0 {
request.Header["Authorization"] = "Bearer " + c.token
pool := x509.NewCertPool()
pool.AppendCertsFromPEM(c.caCert)
c.tls = &tls.Config{RootCAs: pool}
}
res, body, errs := request.TLSClientConfig(c.tls).EndBytes()
if errs != nil {
return nil, fmt.Errorf("failed to create request: GET %q : %v", getURL, errs)
}
if res.StatusCode != http.StatusOK {
return nil, fmt.Errorf("http error %d GET %q: %q", res.StatusCode, getURL, string(body))
}
var serviceList ServiceList
if err := json.Unmarshal(body, &serviceList); err != nil {
return nil, fmt.Errorf("failed to decode list of services resources: %v", err)
}
services := serviceList.Items[:0]
for _, service := range serviceList.Items {
if predicate(service) {
services = append(services, service)
}
}
return services, nil
}