examples: Add took to generate a JWT for testing

Cargo.toml

@@ -31,3 +31,5 @@ serial_test = "2.0.0"
 tempfile = "3.8.1"
 tower = { version = "0.4.13", features = ["util"] }
 
+[[example]]
+name = "make-token"

examples/make-token.rs

@@ -0,0 +1,47 @@
+use std::time;
+
+use argon2::Argon2;
+use jsonwebtoken::{encode, EncodingKey};
+use serde::Serialize;
+use uuid::Uuid;
+
+#[derive(Debug, Serialize)]
+struct Claims {
+    sub: String,
+    iss: String,
+    aud: String,
+    iat: u64,
+    nbf: u64,
+    exp: u64,
+}
+
+fn main() {
+    let args: Vec<_> = std::env::args().collect();
+    let hostname = &args[1];
+    let machine_id = Uuid::parse_str(&args[2]).unwrap();
+    let audience = &args[3];
+
+    let now = time::SystemTime::now()
+        .duration_since(time::UNIX_EPOCH)
+        .unwrap()
+        .as_secs();
+    let claims = Claims {
+        sub: hostname.into(),
+        iss: hostname.into(),
+        aud: audience.into(),
+        nbf: now - 60,
+        iat: now,
+        exp: now + 60,
+    };
+    let mut secret = [0u8; 32];
+    Argon2::default()
+        .hash_password_into(
+            machine_id.as_bytes(),
+            hostname.as_bytes(),
+            &mut secret,
+        )
+        .unwrap();
+    let key = EncodingKey::from_secret(&secret);
+    eprintln!("{:?}", claims);
+    println!("{}", encode(&Default::default(), &claims, &key).unwrap());
+}