func (r *marathonClient) apiCall(method, uri, body string, result interface{}) (int, string, error) {
glog.V(DEBUG_LEVEL).Infof("[api]: method: %s, uri: %s, body: %s", method, uri, body)
status, content, _, err := r.httpRequest(method, uri, body)
if err != nil {
return 0, "", err
}
glog.V(DEBUG_LEVEL).Infof("[api] result: status: %d, content: %s\n", status, content)
if status >= 200 && status <= 299 {
if result != nil {
if err := r.decodeRequest(strings.NewReader(content), result); err != nil {
glog.V(DEBUG_LEVEL).Infof("failed to unmarshall the response from marathon, error: %s", err)
return status, content, ErrInvalidResponse
}
}
return status, content, nil
}
switch status {
case 500:
return status, "", ErrInvalidResponse
case 404:
return status, "", ErrDoesNotExist
}
// step: lets decode into a error message
var message struct {
Message string `json:"message"`
}
if err := r.decodeRequest(strings.NewReader(content), &message); err != nil {
return status, content, ErrInvalidResponse
}
errorMessage := "unknown error"
if message.Message != "" {
errorMessage = message.Message
}
return status, "", fmt.Errorf("%s", errorMessage)
}
func (r *marathonClient) handleMarathonEvent(writer http.ResponseWriter, request *http.Request) {
body, err := ioutil.ReadAll(request.Body)
if err != nil {
return
}
// step: process the event and decode the event
content := string(body[:])
eventType := new(EventType)
err = json.NewDecoder(strings.NewReader(content)).Decode(eventType)
if err != nil {
glog.V(DEBUG_LEVEL).Infof("failed to decode the event type, content: %s, error: %s", content, err)
return
}
// step: check the type is handled
event, err := r.GetEvent(eventType.EventType)
if err != nil {
glog.V(DEBUG_LEVEL).Infof("unable to retrieve the event, type: %s", eventType.EventType)
return
}
// step: lets decode message
err = json.NewDecoder(strings.NewReader(content)).Decode(event.Event)
if err != nil {
glog.V(DEBUG_LEVEL).Infof("failed to decode the event type: %d, name: %s error: %s", event.ID, err)
return
}
r.RLock()
defer r.RUnlock()
// step: check if anyone is listen for this event
for channel, filter := range r.listeners {
// step: check if this listener wants this event type
if event.ID&filter != 0 {
go func(ch EventsChannel, e *Event) {
ch <- e
}(channel, event)
}
}
}
func main() {
flag.Parse()
if Options.method_file == "" {
glog.Errorf("You have not specified the methods file to import")
os.Exit(1)
}
// step: open and read in the methods yaml
contents, err := ioutil.ReadFile(Options.method_file)
if err != nil {
glog.Errorf("Failed to open|read the methods file: %s, error: %s", Options.method_file, err)
os.Exit(1)
}
// step: unmarshal the yaml
var methods []*RestMethod
err = yaml.Unmarshal([]byte(contents), &methods)
if err != nil {
glog.Errorf("Failed to unmarshall the method yaml file: %s, error: %s", Options.method_file, err)
os.Exit(1)
}
// step: construct a hash from the methods
uris := make(map[string]*string, 0)
for _, method := range methods {
uris[fmt.Sprintf("%s:%s", method.Method, method.URI)] = &method.Content
}
http.HandleFunc("/", func(writer http.ResponseWriter, reader *http.Request) {
key := fmt.Sprintf("%s:%s", reader.Method, reader.RequestURI)
glog.V(4).Infof("Request: uri: %s, method: %s", reader.RequestURI, reader.Method)
if content, found := uris[key]; found {
glog.V(4).Infof("Content: %s", *content)
writer.Header().Add("Content-Type", "application/json")
writer.Write([]byte(*content))
} else if !found {
http.Error(writer, "not found", 404)
}
})
glog.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", Options.port), nil))
}
// UpdateApplication updates an application in Marathon
// application: the structure holding the application configuration
func (r *marathonClient) UpdateApplication(application *Application) (*DeploymentID, error) {
result := new(DeploymentID)
glog.V(DEBUG_LEVEL).Infof("updating application: %s", application)
uri := fmt.Sprintf("%s/%s", MARATHON_API_APPS, trimRootPath(application.ID))
if err := r.apiPut(uri, &application, result); err != nil {
return nil, err
}
return result, nil
}
// ScaleApplicationInstances changes the number of instance an application is running
// name: the id used to identify the application
// instances: the number of instances you wish to change to
// force: used to force the scale operation in case of blocked deployment
func (r *marathonClient) ScaleApplicationInstances(name string, instances int, force bool) (*DeploymentID, error) {
glog.V(DEBUG_LEVEL).Infof("scaling the application: %s, instance: %d", name, instances)
changes := new(Application)
changes.ID = validateID(name)
changes.Instances = instances
uri := fmt.Sprintf("%s/%s?force=%t", MARATHON_API_APPS, trimRootPath(name), force)
deployID := new(DeploymentID)
if err := r.apiPut(uri, &changes, deployID); err != nil {
return nil, err
}
return deployID, nil
}
// RestartApplication performs a rolling restart of marathon application
// name: the id used to identify the application
func (r *marathonClient) RestartApplication(name string, force bool) (*DeploymentID, error) {
glog.V(DEBUG_LEVEL).Infof("restarting the application: %s, force: %s", name, force)
deployment := new(DeploymentID)
var options struct {
Force bool `json:"force"`
}
options.Force = force
if err := r.apiPost(fmt.Sprintf("%s/%s/restart", MARATHON_API_APPS, trimRootPath(name)), &options, deployment); err != nil {
return nil, err
}
return deployment, nil
}
// AddEventsListener adds your self as a listener to events from Marathon
// channel: a EventsChannel used to receive event on
func (r *marathonClient) AddEventsListener(channel EventsChannel, filter int) error {
r.Lock()
defer r.Unlock()
// step: someone has asked to start listening to event, we need to register for events
// if we haven't done so already
if err := r.RegisterSubscription(); err != nil {
return err
}
if _, found := r.listeners[channel]; !found {
glog.V(DEBUG_LEVEL).Infof("adding a watch for events: %d, channel: %v", filter, channel)
r.listeners[channel] = filter
}
return nil
}
func (r *marathonClient) httpRequest(method, uri, body string) (int, string, *http.Response, error) {
var content string
// step: get a member from the cluster
marathon, err := r.cluster.GetMember()
if err != nil {
return 0, "", nil, err
}
url := fmt.Sprintf("%s/%s", marathon, uri)
glog.V(DEBUG_LEVEL).Infof("[http] request: %s, uri: %s, url: %s", method, uri, url)
// step: make the http request to marathon
request, err := http.NewRequest(method, url, strings.NewReader(body))
if err != nil {
return 0, "", nil, err
}
// step: add any basic auth and the content headers
if r.config.HttpBasicAuthUser != "" {
request.SetBasicAuth(r.config.HttpBasicAuthUser, r.config.HttpBasicPassword)
}
request.Header.Add("Content-Type", "application/json")
request.Header.Add("Accept", "application/json")
response, err := r.httpClient.Do(request)
if err != nil {
r.cluster.MarkDown()
// step: retry the request with another endpoint
return r.httpRequest(method, uri, body)
}
if response.ContentLength != 0 {
responseContent, err := ioutil.ReadAll(response.Body)
if err != nil {
return response.StatusCode, "", response, err
}
content = string(responseContent)
}
return response.StatusCode, content, response, nil
}
