oc-lib/tools/nats_caller.go
2024-09-04 10:53:12 +02:00

66 lines
1.7 KiB
Go

package tools
import (
"encoding/json"
"strings"
"cloud.o-forge.io/core/oc-lib/config"
"github.com/nats-io/nats.go"
)
// NATS Method Enum defines the different methods that can be used to interact with the NATS server
type NATSMethod int
const (
REMOVE NATSMethod = iota
CREATE
)
// NameToMethod returns the NATSMethod enum value from a string
func NameToMethod(name string) NATSMethod {
for _, v := range [...]NATSMethod{REMOVE, CREATE} {
if strings.Contains(strings.ToLower(v.String()), strings.ToLower(name)) {
return v
}
}
return -1
}
// GenerateKey generates a key for the NATSMethod usefull for standard key based on data name & method
func (d NATSMethod) GenerateKey(name string) string {
return name + "_" + d.String()
}
// String returns the string of the enum
func (d NATSMethod) String() string {
return [...]string{"remove", "create", "discovery"}[d]
}
type natsCaller struct{}
// NewNATSCaller creates a new instance of the NATS Caller
func NewNATSCaller() *natsCaller {
return &natsCaller{}
}
// SetNATSPub sets a message to the NATS server
func (o *natsCaller) SetNATSPub(dataName string, method NATSMethod, data interface{}) string {
if config.GetConfig().NATSUrl == "" {
return " -> NATS_SERVER is not set"
}
nc, err := nats.Connect(config.GetConfig().NATSUrl)
if err != nil {
return " -> Could not reach NATS server : " + err.Error()
}
defer nc.Close()
js, err := json.Marshal(data)
if err != nil {
return " -> " + err.Error()
}
err = nc.Publish(method.GenerateKey(dataName), js) // Publish the message on the NATS server with a channel name based on the data name (or whatever start) and the method
if err != nil {
return " -> " + err.Error() // Return an error if the message could not be published
}
return ""
}