Implement PermissionSystem::getRoleList()

Closes: #62

bffhd/authorization/roles.rs

@@ -27,6 +27,10 @@ impl Roles {
         self.roles.get(roleid)
     }
 
+    pub fn list(&self) -> impl Iterator<Item = &String> {
+        self.roles.keys()
+    }
+
     /// Tally a role dependency tree into a set
     ///
     /// A Default implementation exists which adapter may overwrite with more efficient

bffhd/capnp/permissionsystem.rs

@@ -1,13 +1,38 @@
-use api::permissionsystem_capnp::permission_system::info::Server as PermissionSystem;
+use crate::authorization::roles::Role;
+use crate::Roles;
+use api::permissionsystem_capnp::permission_system::info::{
+    GetRoleListParams, GetRoleListResults, Server as PermissionSystem,
+};
+use capnp::capability::Promise;
+use capnp::Error;
 
 use crate::session::SessionHandle;
 
-pub struct Permissions;
+pub struct Permissions {
+    roles: Roles,
+}
 
 impl Permissions {
-    pub fn new(_session: SessionHandle) -> Self {
-        Self
+    pub fn new(session: SessionHandle) -> Self {
+        Self {
+            roles: session.roles,
+        }
     }
 }
 
-impl PermissionSystem for Permissions {}
+impl PermissionSystem for Permissions {
+    fn get_role_list(
+        &mut self,
+        _: GetRoleListParams,
+        mut results: GetRoleListResults,
+    ) -> Promise<(), Error> {
+        let roles = self.roles.list().collect::<Vec<&String>>();
+        let mut builder = results.get();
+        let mut b = builder.init_role_list(roles.len() as u32);
+        for (i, role) in roles.into_iter().enumerate() {
+            let mut role_builder = b.reborrow().get(i as u32);
+            role_builder.set_name(role);
+        }
+        Promise::ok(())
+    }
+}