Authenticating with a Token

Tokens are basically random strings, much like a password, and can provide a simple authentication mechanism in some situations. However, tokens are only as safe as they are secret so other authentication schemes can provide more security in large installations. It is highly recommended to use one of the other NATS authentication mechanisms.

For this example, start the server using:

> nats-server --auth mytoken

The code uses localhost:4222 so that you can start the server on your machine to try them out.

Connecting with a Token

Go
Java
JavaScript
Python
Ruby
TypeScript
Go
// Set a token
nc, err := nats.Connect("127.0.0.1", nats.Name("API Token Example"), nats.Token("mytoken"))
if err != nil {
log.Fatal(err)
}
defer nc.Close()
// Do something with the connection
Java
Options options = new Options.Builder().
server("nats://localhost:4222").
token("mytoken"). // Set a token
build();
Connection nc = Nats.connect(options);
// Do something with the connection
nc.close();
JavaScript
let nc = NATS.connect({url: `nats://127.0.0.1:${port}`, token: "mytoken!"});
Python
nc = NATS()
await nc.connect(servers=["nats://demo.nats.io:4222"], token="mytoken")
# Do something with the connection.
Ruby
NATS.start(token: "mytoken") do |nc|
puts "Connected using token"
end
TypeScript
let nc = await connect({url: server.nats, token: "mytoken"});

Connecting with a Token in the URL

Some client libraries will allow you to pass the token as part of the server URL using the form:

nats://token@server:port

Again, once you construct this URL you can connect as if this was a normal URL.

Go
Java
JavaScript
Python
Ruby
TypeScript
Go
// Token in URL
nc, err := nats.Connect("mytoken@localhost")
if err != nil {
log.Fatal(err)
}
defer nc.Close()
// Do something with the connection
Java
Connection nc = Nats.connect("nats://mytoken@localhost:4222");//Token in URL
// Do something with the connection
nc.close();
JavaScript
let url = `nats://mytoken@127.0.0.1:${port}`;
let nc = NATS.connect({url: url});
Python
nc = NATS()
await nc.connect(servers=["nats://mytoken@demo.nats.io:4222"])
# Do something with the connection.
Ruby
NATS.start("mytoken@127.0.0.1:4222") do |nc|
puts "Connected using token!"
end
TypeScript
let url = `nats://:mytoken@127.0.0.1:${port}`;
let nc = await connect({url: url});