128 lines
3.0 KiB
Go
128 lines
3.0 KiB
Go
package nats
|
|
|
|
import (
|
|
"github.com/nats-io/nats"
|
|
"gobot.io/x/gobot"
|
|
"net/url"
|
|
"strings"
|
|
)
|
|
|
|
// Adaptor is a configuration struct for interacting with a NATS server.
|
|
// Name is a logical name for the adaptor/nats server connection.
|
|
// Host is in the form "localhost:4222" which is the hostname/ip and port of the nats server.
|
|
// ClientID is a unique identifier integer that specifies the identity of the client.
|
|
type Adaptor struct {
|
|
name string
|
|
Host string
|
|
clientID int
|
|
username string
|
|
password string
|
|
client *nats.Conn
|
|
connect func() (*nats.Conn, error)
|
|
}
|
|
|
|
// Message is a message received from the server.
|
|
type Message *nats.Msg
|
|
|
|
// NewAdaptor populates a new NATS Adaptor.
|
|
func NewAdaptor(host string, clientID int, options ...nats.Option) *Adaptor {
|
|
hosts, err := processHostString(host)
|
|
|
|
return &Adaptor{
|
|
name: gobot.DefaultName("NATS"),
|
|
Host: hosts,
|
|
clientID: clientID,
|
|
connect: func() (*nats.Conn, error) {
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return nats.Connect(hosts, options...)
|
|
},
|
|
}
|
|
}
|
|
|
|
// NewAdaptorWithAuth populates a NATS Adaptor including username and password.
|
|
func NewAdaptorWithAuth(host string, clientID int, username string, password string, options ...nats.Option) *Adaptor {
|
|
hosts, err := processHostString(host)
|
|
|
|
return &Adaptor{
|
|
Host: hosts,
|
|
clientID: clientID,
|
|
username: username,
|
|
password: password,
|
|
connect: func() (*nats.Conn, error) {
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return nats.Connect(hosts, append(options, nats.UserInfo(username, password))...)
|
|
},
|
|
}
|
|
}
|
|
|
|
func processHostString(host string) (string, error) {
|
|
urls := strings.Split(host, ",")
|
|
for i, s := range urls {
|
|
s = strings.TrimSpace(s)
|
|
if !strings.HasPrefix(s, "tls://") && !strings.HasPrefix(s, "nats://") {
|
|
s = "nats://" + s
|
|
}
|
|
|
|
u, err := url.Parse(s)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
|
|
urls[i] = u.String()
|
|
}
|
|
|
|
return strings.Join(urls, ","), nil
|
|
}
|
|
|
|
// Name returns the logical client name.
|
|
func (a *Adaptor) Name() string { return a.name }
|
|
|
|
// SetName sets the logical client name.
|
|
func (a *Adaptor) SetName(n string) { a.name = n }
|
|
|
|
// Connect makes a connection to the Nats server.
|
|
func (a *Adaptor) Connect() (err error) {
|
|
a.client, err = a.connect()
|
|
return
|
|
}
|
|
|
|
// Disconnect from the nats server.
|
|
func (a *Adaptor) Disconnect() (err error) {
|
|
if a.client != nil {
|
|
a.client.Close()
|
|
}
|
|
return
|
|
}
|
|
|
|
// Finalize is simply a helper method for the disconnect.
|
|
func (a *Adaptor) Finalize() (err error) {
|
|
a.Disconnect()
|
|
return
|
|
}
|
|
|
|
// Publish sends a message with the particular topic to the nats server.
|
|
func (a *Adaptor) Publish(topic string, message []byte) bool {
|
|
if a.client == nil {
|
|
return false
|
|
}
|
|
a.client.Publish(topic, message)
|
|
return true
|
|
}
|
|
|
|
// On is an event-handler style subscriber to a particular topic (named event).
|
|
// Supply a handler function to use the bytes returned by the server.
|
|
func (a *Adaptor) On(event string, f func(msg Message)) bool {
|
|
if a.client == nil {
|
|
return false
|
|
}
|
|
a.client.Subscribe(event, func(msg *nats.Msg) {
|
|
f(msg)
|
|
})
|
|
|
|
return true
|
|
}
|