mirror of
https://github.com/postmannen/ctrl.git
synced 2024-12-15 17:51:15 +00:00
122 lines
3.5 KiB
Go
122 lines
3.5 KiB
Go
// NB:
|
|
// When adding new constants for the Method or CommandOrEvent
|
|
// types, make sure to also add them to the map
|
|
// <Method/CommandOrEvent>Available since the this will be used
|
|
// to check if the message values are valid later on.
|
|
|
|
package steward
|
|
|
|
import (
|
|
"fmt"
|
|
"log"
|
|
"os/exec"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
)
|
|
|
|
// ------------------------------------------------------------
|
|
|
|
// Method is used to specify the actual function/method that
|
|
// is represented in a typed manner.
|
|
type Method string
|
|
|
|
func (m Method) GetMethodsAvailable() MethodsAvailable {
|
|
ma := MethodsAvailable{
|
|
topics: map[Method]methodHandler{
|
|
ShellCommand: methodCommandShellCommand{},
|
|
TextLogging: methodEventTextLogging{},
|
|
SayHello: methodEventSayHello{},
|
|
},
|
|
}
|
|
|
|
return ma
|
|
}
|
|
|
|
const (
|
|
// Shell command to be executed via f.ex. bash
|
|
ShellCommand Method = "ShellCommand"
|
|
// Send text logging to some host
|
|
TextLogging Method = "TextLogging"
|
|
// Send Hello I'm here message
|
|
SayHello Method = "SayHello"
|
|
)
|
|
|
|
type MethodsAvailable struct {
|
|
topics map[Method]methodHandler
|
|
}
|
|
|
|
// Check if exists will check if the Method is defined. If true the bool
|
|
// value will be set to true, and the methodHandler function for that type
|
|
// will be returned.
|
|
func (ma MethodsAvailable) CheckIfExists(m Method) (methodHandler, bool) {
|
|
mFunc, ok := ma.topics[m]
|
|
if ok {
|
|
// fmt.Printf("******THE TOPIC EXISTS: %v******\n", m)
|
|
return mFunc, true
|
|
} else {
|
|
// fmt.Printf("******THE TOPIC DO NOT EXIST: %v******\n", m)
|
|
return nil, false
|
|
}
|
|
}
|
|
|
|
// ------------------------------------------------------------
|
|
// Subscriber method handlers
|
|
// ------------------------------------------------------------
|
|
|
|
type methodHandler interface {
|
|
handler(server *server, message Message, node string) ([]byte, error)
|
|
}
|
|
|
|
type methodCommandShellCommand struct{}
|
|
|
|
func (m methodCommandShellCommand) handler(s *server, message Message, node string) ([]byte, error) {
|
|
// Since the command to execute is at the first position in the
|
|
// slice we need to slice it out. The arguments are at the
|
|
// remaining positions.
|
|
c := message.Data[0]
|
|
a := message.Data[1:]
|
|
cmd := exec.Command(c, a...)
|
|
//cmd.Stdout = os.Stdout
|
|
out, err := cmd.CombinedOutput()
|
|
if err != nil {
|
|
log.Printf("error: execution of command failed: %v\n", err)
|
|
}
|
|
|
|
outMsg := []byte(fmt.Sprintf("confirmed from node: %v: messageID: %v\n---\n%s---", node, message.ID, out))
|
|
return outMsg, nil
|
|
}
|
|
|
|
// -----
|
|
|
|
type methodEventTextLogging struct{}
|
|
|
|
func (m methodEventTextLogging) handler(s *server, message Message, node string) ([]byte, error) {
|
|
for _, d := range message.Data {
|
|
s.logCh <- []byte(d)
|
|
}
|
|
|
|
outMsg := []byte("confirmed from: " + node + ": " + fmt.Sprint(message.ID))
|
|
return outMsg, nil
|
|
}
|
|
|
|
// -----
|
|
|
|
type methodEventSayHello struct{}
|
|
|
|
func (m methodEventSayHello) handler(s *server, message Message, node string) ([]byte, error) {
|
|
log.Printf("################## Received hello from %v ##################\n", message.FromNode)
|
|
// Since the handler is only called to handle a specific type of message we need
|
|
// to store it elsewhere, and choice for now is under s.metrics.sayHelloNodes
|
|
s.metrics.sayHelloNodes[message.FromNode] = struct{}{}
|
|
|
|
// update the prometheus metrics
|
|
s.metrics.metricsCh <- metricType{
|
|
metric: prometheus.NewGauge(prometheus.GaugeOpts{
|
|
Name: "hello_nodes",
|
|
Help: "The current number of total nodes who have said hello",
|
|
}),
|
|
value: float64(len(s.metrics.sayHelloNodes)),
|
|
}
|
|
outMsg := []byte("confirmed from: " + node + ": " + fmt.Sprint(message.ID))
|
|
return outMsg, nil
|
|
}
|