traefik/vendor/github.com/gambol99/go-marathon/client.go
Timo Reimann 219a6372b0 Upgrade go-marathon to 15ea23e.
Our vendored copy contains a bug that causes unavailable Marathon nodes
to never be marked as available again due to a misconstruction in the
URL to the Marathon health check / ping endpoint used by go-marathon
internally.

A fix[1] has been published.

[1]https://github.com/gambol99/go-marathon/pull/283
2017-05-22 20:52:24 +02:00

377 lines
12 KiB
Go

/*
Copyright 2014 Rohith All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package marathon
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"io"
"io/ioutil"
"log"
"net/http"
"net/url"
"regexp"
"strings"
"sync"
"time"
)
// Marathon is the interface to the marathon API
type Marathon interface {
// -- APPLICATIONS ---
// get a listing of the application ids
ListApplications(url.Values) ([]string, error)
// a list of application versions
ApplicationVersions(name string) (*ApplicationVersions, error)
// check a application version exists
HasApplicationVersion(name, version string) (bool, error)
// change an application to a different version
SetApplicationVersion(name string, version *ApplicationVersion) (*DeploymentID, error)
// check if an application is ok
ApplicationOK(name string) (bool, error)
// create an application in marathon
CreateApplication(application *Application) (*Application, error)
// delete an application
DeleteApplication(name string, force bool) (*DeploymentID, error)
// update an application in marathon
UpdateApplication(application *Application, force bool) (*DeploymentID, error)
// a list of deployments on a application
ApplicationDeployments(name string) ([]*DeploymentID, error)
// scale a application
ScaleApplicationInstances(name string, instances int, force bool) (*DeploymentID, error)
// restart an application
RestartApplication(name string, force bool) (*DeploymentID, error)
// get a list of applications from marathon
Applications(url.Values) (*Applications, error)
// get an application by name
Application(name string) (*Application, error)
// get an application by options
ApplicationBy(name string, opts *GetAppOpts) (*Application, error)
// get an application by name and version
ApplicationByVersion(name, version string) (*Application, error)
// wait of application
WaitOnApplication(name string, timeout time.Duration) error
// -- TASKS ---
// get a list of tasks for a specific application
Tasks(application string) (*Tasks, error)
// get a list of all tasks
AllTasks(opts *AllTasksOpts) (*Tasks, error)
// get the endpoints for a service on a application
TaskEndpoints(name string, port int, healthCheck bool) ([]string, error)
// kill all the tasks for any application
KillApplicationTasks(applicationID string, opts *KillApplicationTasksOpts) (*Tasks, error)
// kill a single task
KillTask(taskID string, opts *KillTaskOpts) (*Task, error)
// kill the given array of tasks
KillTasks(taskIDs []string, opts *KillTaskOpts) error
// --- GROUPS ---
// list all the groups in the system
Groups() (*Groups, error)
// retrieve a specific group from marathon
Group(name string) (*Group, error)
// list all groups in marathon by options
GroupsBy(opts *GetGroupOpts) (*Groups, error)
// retrieve a specific group from marathon by options
GroupBy(name string, opts *GetGroupOpts) (*Group, error)
// create a group deployment
CreateGroup(group *Group) error
// delete a group
DeleteGroup(name string, force bool) (*DeploymentID, error)
// update a groups
UpdateGroup(id string, group *Group, force bool) (*DeploymentID, error)
// check if a group exists
HasGroup(name string) (bool, error)
// wait for an group to be deployed
WaitOnGroup(name string, timeout time.Duration) error
// --- DEPLOYMENTS ---
// get a list of the deployments
Deployments() ([]*Deployment, error)
// delete a deployment
DeleteDeployment(id string, force bool) (*DeploymentID, error)
// check to see if a deployment exists
HasDeployment(id string) (bool, error)
// wait of a deployment to finish
WaitOnDeployment(id string, timeout time.Duration) error
// --- SUBSCRIPTIONS ---
// a list of current subscriptions
Subscriptions() (*Subscriptions, error)
// add a events listener
AddEventsListener(filter int) (EventsChannel, error)
// remove a events listener
RemoveEventsListener(channel EventsChannel)
// Subscribe a callback URL
Subscribe(string) error
// Unsubscribe a callback URL
Unsubscribe(string) error
// --- QUEUE ---
// get marathon launch queue
Queue() (*Queue, error)
// resets task launch delay of the specific application
DeleteQueueDelay(appID string) error
// --- MISC ---
// get the marathon url
GetMarathonURL() string
// ping the marathon
Ping() (bool, error)
// grab the marathon server info
Info() (*Info, error)
// retrieve the leader info
Leader() (string, error)
// cause the current leader to abdicate
AbdicateLeader() (string, error)
}
var (
// ErrInvalidResponse is thrown when marathon responds with invalid or error response
ErrInvalidResponse = errors.New("invalid response from Marathon")
// ErrMarathonDown is thrown when all the marathon endpoints are down
ErrMarathonDown = errors.New("all the Marathon hosts are presently down")
// ErrTimeoutError is thrown when the operation has timed out
ErrTimeoutError = errors.New("the operation has timed out")
)
// EventsChannelContext holds contextual data for an EventsChannel.
type EventsChannelContext struct {
filter int
done chan struct{}
completion *sync.WaitGroup
}
type marathonClient struct {
sync.RWMutex
// the configuration for the client
config Config
// the flag used to prevent multiple SSE subscriptions
subscribedToSSE bool
// the ip address of the client
ipAddress string
// the http server
eventsHTTP *http.Server
// the marathon hosts
hosts *cluster
// a map of service you wish to listen to
listeners map[EventsChannel]EventsChannelContext
// a custom logger for debug log messages
debugLog *log.Logger
// the marathon HTTP client to ensure consistency in requests
client *httpClient
}
type httpClient struct {
// the configuration for the marathon HTTP client
config Config
}
// NewClient creates a new marathon client
// config: the configuration to use
func NewClient(config Config) (Marathon, error) {
// step: if no http client, set to default
if config.HTTPClient == nil {
config.HTTPClient = http.DefaultClient
}
// step: if no polling wait time is set, default to 500 milliseconds.
if config.PollingWaitTime == 0 {
config.PollingWaitTime = defaultPollingWaitTime
}
// step: setup shared client
client := &httpClient{config: config}
// step: create a new cluster
hosts, err := newCluster(client, config.URL, config.DCOSToken != "")
if err != nil {
return nil, err
}
debugLogOutput := config.LogOutput
if debugLogOutput == nil {
debugLogOutput = ioutil.Discard
}
return &marathonClient{
config: config,
listeners: make(map[EventsChannel]EventsChannelContext),
hosts: hosts,
debugLog: log.New(debugLogOutput, "", 0),
client: client,
}, nil
}
// GetMarathonURL retrieves the marathon url
func (r *marathonClient) GetMarathonURL() string {
return r.config.URL
}
// Ping pings the current marathon endpoint (note, this is not a ICMP ping, but a rest api call)
func (r *marathonClient) Ping() (bool, error) {
if err := r.apiGet(marathonAPIPing, nil, nil); err != nil {
return false, err
}
return true, nil
}
func (r *marathonClient) apiGet(path string, post, result interface{}) error {
return r.apiCall("GET", path, post, result)
}
func (r *marathonClient) apiPut(path string, post, result interface{}) error {
return r.apiCall("PUT", path, post, result)
}
func (r *marathonClient) apiPost(path string, post, result interface{}) error {
return r.apiCall("POST", path, post, result)
}
func (r *marathonClient) apiDelete(path string, post, result interface{}) error {
return r.apiCall("DELETE", path, post, result)
}
func (r *marathonClient) apiCall(method, path string, body, result interface{}) error {
for {
// step: marshall the request to json
var requestBody []byte
var err error
if body != nil {
if requestBody, err = json.Marshal(body); err != nil {
return err
}
}
// step: create the API request
request, member, err := r.buildAPIRequest(method, path, bytes.NewReader(requestBody))
if err != nil {
return err
}
// step: perform the API request
response, err := r.client.Do(request)
if err != nil {
r.hosts.markDown(member)
// step: attempt the request on another member
r.debugLog.Printf("apiCall(): request failed on host: %s, error: %s, trying another\n", member, err)
continue
}
defer response.Body.Close()
// step: read the response body
respBody, err := ioutil.ReadAll(response.Body)
if err != nil {
return err
}
if len(requestBody) > 0 {
r.debugLog.Printf("apiCall(): %v %v %s returned %v %s\n", request.Method, request.URL.String(), requestBody, response.Status, oneLogLine(respBody))
} else {
r.debugLog.Printf("apiCall(): %v %v returned %v %s\n", request.Method, request.URL.String(), response.Status, oneLogLine(respBody))
}
// step: check for a successfull response
if response.StatusCode >= 200 && response.StatusCode <= 299 {
if result != nil {
if err := json.Unmarshal(respBody, result); err != nil {
r.debugLog.Printf("apiCall(): failed to unmarshall the response from marathon, error: %s\n", err)
return ErrInvalidResponse
}
}
return nil
}
// step: if the member node returns a >= 500 && <= 599 we should try another node?
if response.StatusCode >= 500 && response.StatusCode <= 599 {
// step: mark the host as down
r.hosts.markDown(member)
r.debugLog.Printf("apiCall(): request failed, host: %s, status: %d, trying another\n", member, response.StatusCode)
continue
}
return NewAPIError(response.StatusCode, respBody)
}
}
// buildAPIRequest creates a default API request
func (r *marathonClient) buildAPIRequest(method, path string, reader io.Reader) (request *http.Request, member string, err error) {
// Grab a member from the cluster
member, err = r.hosts.getMember()
if err != nil {
return nil, "", ErrMarathonDown
}
// Build the HTTP request to Marathon
request, err = r.client.buildMarathonRequest(method, member, path, reader)
if err != nil {
return nil, member, err
}
return request, member, nil
}
// buildMarathonRequest creates a new HTTP request and configures it according to the *httpClient configuration.
// The path must not contain a leading "/", otherwise buildMarathonRequest will panic.
func (rc *httpClient) buildMarathonRequest(method string, member string, path string, reader io.Reader) (request *http.Request, err error) {
if strings.HasPrefix(path, "/") {
panic(fmt.Sprintf("Path '%s' must not start with a leading slash", path))
}
// Create the endpoint URL
url := fmt.Sprintf("%s/%s", member, path)
// Instantiate an HTTP request
request, err = http.NewRequest(method, url, reader)
if err != nil {
return nil, err
}
// Add any basic auth and the content headers
if rc.config.HTTPBasicAuthUser != "" && rc.config.HTTPBasicPassword != "" {
request.SetBasicAuth(rc.config.HTTPBasicAuthUser, rc.config.HTTPBasicPassword)
}
if rc.config.DCOSToken != "" {
request.Header.Add("Authorization", "token="+rc.config.DCOSToken)
}
request.Header.Add("Content-Type", "application/json")
request.Header.Add("Accept", "application/json")
return request, nil
}
func (rc *httpClient) Do(request *http.Request) (response *http.Response, err error) {
return rc.config.HTTPClient.Do(request)
}
var oneLogLineRegex = regexp.MustCompile(`(?m)^\s*`)
// oneLogLine removes indentation at the beginning of each line and
// escapes new line characters.
func oneLogLine(in []byte) []byte {
return bytes.Replace(oneLogLineRegex.ReplaceAll(in, nil), []byte("\n"), []byte("\\n "), -1)
}