From 750ae0c34b5c93286e61b8530168ea45c8d1c32b Mon Sep 17 00:00:00 2001
From: Nadja Reitzenstein <me@dequbed.space>
Date: Thu, 28 Apr 2022 19:01:15 +0200
Subject: [PATCH 1/4] Make the API be more proper regarding user mgmnt

---
 general.capnp    | 10 ++++++++++
 usersystem.capnp | 16 +++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/general.capnp b/general.capnp
index 01460cc..8819eef 100644
--- a/general.capnp
+++ b/general.capnp
@@ -33,3 +33,13 @@ struct Optional(T) {
         just @1 :T;
     }
 }
+
+struct Fallible(T, E) {
+    # Some operations can fail in several expected ways.
+    # In those cases returning an `Optional` doesn't transfer information about the way that the
+    # operation failed. `Fallible` contains this information in the generic `E` type.
+    union {
+        successful @0 :T;
+        failed @1 :E;
+    }
+}
diff --git a/usersystem.capnp b/usersystem.capnp
index f5754c4..722065b 100644
--- a/usersystem.capnp
+++ b/usersystem.capnp
@@ -8,6 +8,8 @@ $CSharp.namespace("FabAccessAPI.Schema");
 
 using General = import "general.capnp";
 using User = import "user.capnp".User;
+using Optional = General.Optional;
+using Fallible = General.Fallible;
 
 struct UserSystem
 {
@@ -16,11 +18,23 @@ struct UserSystem
     	getUserSelf @0 ( ) -> User;
 	}
 
+	search @2 :Search;
+	interface Search $CSharp.name("SearchInterface") {
+	    getUserByName @0 (username: Text) -> Optional(User);
+	}
+
 	manage @1 :Manage;
     interface Manage $CSharp.name("ManageInterface") {
     	getUserList @0 () -> ( user_list :List(User) );
 
-    	addUser @1 (username :Text, password: Text) -> User;
+        enum AddUserError {
+            alreadyExists @0;
+            # An user with that username already exists
+            usernameInvalid @1;
+            # The provided username is unusable, e.g. contains invalid characters,
+            # is too long or too short.
+        }
+    	addUser @1 (username :Text, password: Text) -> Fallible(User, AddUserError);
     	removeUser @2 (user: User);
 	}
 }

From 93f130873eb23357a32cc04269dbf927c9041b17 Mon Sep 17 00:00:00 2001
From: Nadja Reitzenstein <me@dequbed.space>
Date: Thu, 28 Apr 2022 20:10:06 +0200
Subject: [PATCH 2/4] stay backwards compatible

---
 general.capnp    |  6 +++---
 usersystem.capnp | 21 +++++++++++++--------
 2 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/general.capnp b/general.capnp
index 8819eef..9ce6218 100644
--- a/general.capnp
+++ b/general.capnp
@@ -39,7 +39,7 @@ struct Fallible(T, E) {
     # In those cases returning an `Optional` doesn't transfer information about the way that the
     # operation failed. `Fallible` contains this information in the generic `E` type.
     union {
-        successful @0 :T;
-        failed @1 :E;
+        failed @0 :E;
+        successful @1 :T;
     }
-}
+}
\ No newline at end of file
diff --git a/usersystem.capnp b/usersystem.capnp
index 722065b..0148425 100644
--- a/usersystem.capnp
+++ b/usersystem.capnp
@@ -27,14 +27,19 @@ struct UserSystem
     interface Manage $CSharp.name("ManageInterface") {
     	getUserList @0 () -> ( user_list :List(User) );
 
-        enum AddUserError {
-            alreadyExists @0;
-            # An user with that username already exists
-            usernameInvalid @1;
-            # The provided username is unusable, e.g. contains invalid characters,
-            # is too long or too short.
-        }
-    	addUser @1 (username :Text, password: Text) -> Fallible(User, AddUserError);
+        addUser @1 (username :Text, password: Text) -> User;
     	removeUser @2 (user: User);
+
+        struct AddUserError {
+            enum AddUserError {
+                alreadyExists @0;
+                # An user with that username already exists
+                usernameInvalid @1;
+                # The provided username is unusable, e.g. contains invalid characters,
+                # is too long or too short.
+            }
+            error @0 :AddUserError;
+        }
+    	addUserFallible @3 (username :Text, password: Text) -> Fallible(User, AddUserError);
 	}
 }

From c00a274a16e9ec3e68502131e73648ca9edbcfe3 Mon Sep 17 00:00:00 2001
From: Nadja Reitzenstein <me@dequbed.space>
Date: Thu, 28 Apr 2022 20:11:08 +0200
Subject: [PATCH 3/4] Add deprecation comment

---
 usersystem.capnp | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/usersystem.capnp b/usersystem.capnp
index 0148425..60c2a71 100644
--- a/usersystem.capnp
+++ b/usersystem.capnp
@@ -28,6 +28,8 @@ struct UserSystem
     	getUserList @0 () -> ( user_list :List(User) );
 
         addUser @1 (username :Text, password: Text) -> User;
+        # DEPRECATED: use `addUserFallible` instead
+
     	removeUser @2 (user: User);
 
         struct AddUserError {

From d04d930bd3de31a718459440361ab50dee020e6e Mon Sep 17 00:00:00 2001
From: Nadja Reitzenstein <me@dequbed.space>
Date: Thu, 28 Apr 2022 20:12:16 +0200
Subject: [PATCH 4/4] Add an 'invalid password' error

---
 usersystem.capnp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/usersystem.capnp b/usersystem.capnp
index 60c2a71..ca9ff69 100644
--- a/usersystem.capnp
+++ b/usersystem.capnp
@@ -36,9 +36,13 @@ struct UserSystem
             enum AddUserError {
                 alreadyExists @0;
                 # An user with that username already exists
+
                 usernameInvalid @1;
                 # The provided username is unusable, e.g. contains invalid characters,
                 # is too long or too short.
+
+                passwordInvalid @2;
+                # The provided password is unusable, e.g. it's of zero length
             }
             error @0 :AddUserError;
         }