Generate Auth Keys

Added the ability to generate new auth keys. Can see in the tailscale
logs that new keys are being generated with a 90 day expiration time.
This should be enough to close out issue #7.

src/types.rs

@@ -1,4 +1,95 @@
+use serde::{Deserialize, Serialize};
+
 pub struct ClientAuth {
     pub id: String,
     pub secret: String,
 }
+
+#[derive(Serialize, Deserialize)]
+pub struct AuthKeyRequest {
+    capabilities: CapabilitiesCreate,
+    expiry_seconds: i32,
+    description: String,
+}
+
+impl AuthKeyRequest {
+    pub fn new() -> Self {
+        let create_options = CreateOptions {
+            reusable: false,
+            ephemeral: false,
+            preauthorized: false,
+            tags: Vec::new(),
+        };
+
+        let devices_create = DevicesCreate {
+            create: create_options,
+        };
+
+        let capabilities_create = CapabilitiesCreate {
+            devices: devices_create,
+        };
+
+        Self {
+            capabilities: capabilities_create,
+            expiry_seconds: 3600,
+            description: String::new(),
+        }
+    }
+
+    pub fn is_reusable(&mut self, reusable: bool) {
+        self.capabilities.devices.create.reusable = reusable;
+    }
+
+    pub fn is_ephemeral(&mut self, ephemeral: bool) {
+        self.capabilities.devices.create.ephemeral = ephemeral;
+    }
+
+    pub fn is_preauthorized(&mut self, preauthorized: bool) {
+        self.capabilities.devices.create.preauthorized = preauthorized;
+    }
+
+    pub fn expiry_seconds(&mut self, expiry_seconds: i32) {
+        self.expiry_seconds = expiry_seconds;
+    }
+
+    pub fn description(&mut self, description: String) {
+        self.description = description;
+    }
+
+    pub fn set_tags(&mut self, tags: Vec<String>) {
+        self.capabilities.devices.create.tags = tags;
+    }
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct CapabilitiesCreate {
+    devices: DevicesCreate,
+}
+
+#[derive(Serialize, Deserialize)]
+struct DevicesCreate {
+    create: CreateOptions,
+}
+
+#[derive(Serialize, Deserialize)]
+struct CreateOptions {
+    reusable: bool,
+    ephemeral: bool,
+    preauthorized: bool,
+    tags: Vec<String>,
+}
+
+#[derive(Serialize, Deserialize)]
+pub struct AuthKeyResponse {
+    id: String,
+    key: String,
+    created: String,
+    expires: String,
+    capabilities: CapabilitiesCreate,
+}
+
+impl AuthKeyResponse {
+    pub fn get_auth_key(self) -> String {
+        self.key
+    }
+}