func (s *HTTPServer) AgentMonitor(resp http.ResponseWriter, req *http.Request) (interface{}, error) {
// Only GET supported
if req.Method != "GET" {
resp.WriteHeader(405)
return nil, nil
}
var args structs.DCSpecificRequest
args.Datacenter = s.agent.config.Datacenter
s.parseToken(req, &args.Token)
// Validate that the given token has operator permissions
var reply structs.RaftConfigurationResponse
if err := s.agent.RPC("Operator.RaftGetConfiguration", &args, &reply); err != nil {
return nil, err
}
// Get the provided loglevel
logLevel := req.URL.Query().Get("loglevel")
if logLevel == "" {
logLevel = "INFO"
}
// Upper case the log level
logLevel = strings.ToUpper(logLevel)
// Create a level filter
filter := logger.LevelFilter()
filter.MinLevel = logutils.LogLevel(logLevel)
if !logger.ValidateLevelFilter(filter.MinLevel, filter) {
resp.WriteHeader(400)
resp.Write([]byte(fmt.Sprintf("Unknown log level: %s", filter.MinLevel)))
return nil, nil
}
flusher, ok := resp.(http.Flusher)
if !ok {
return nil, fmt.Errorf("Streaming not supported")
}
// Set up a log handler
handler := &httpLogHandler{
filter: filter,
logCh: make(chan string, 512),
logger: s.logger,
}
s.agent.logWriter.RegisterHandler(handler)
defer s.agent.logWriter.DeregisterHandler(handler)
notify := resp.(http.CloseNotifier).CloseNotify()
// Stream logs until the connection is closed
for {
select {
case <-notify:
s.agent.logWriter.DeregisterHandler(handler)
if handler.droppedCount > 0 {
s.agent.logger.Printf("[WARN] agent: Dropped %d logs during monitor request", handler.droppedCount)
}
return nil, nil
case log := <-handler.logCh:
resp.Write([]byte(log + "\n"))
flusher.Flush()
}
}
return nil, nil
}
