feat(daemon): publish room member statistics over RPC and the CLI

The statistics parsed from the JoinRoom reply were reachable only from the
library. They answer the question `room users` already exists to ask -- who
is in here, and are they worth downloading from -- so they belong on its
output rather than behind a second call.

- proto: room.member_stats, with a RoomUserStatsDto carrying status, share
  counts, free slots and country
- SessionApi::room_member_stats, so local and remote sessions stay
  interchangeable; the status word is decoded through one shared helper
  rather than a third copy of the match
- `room users` now emits status, average_speed, shared_files,
  shared_folders, slots_free and country, each null when the server said
  nothing, documented in SKILL.md
- docs/openrpc.json regenerated from the wire types

soulseek-rs/src/daemon/openrpc.rs

@@ -11,10 +11,11 @@
 use super::proto::{
     Ack, AuthParams, AuthResult, BrowseEvent, DaemonStatus, DirectoriesParams,
     DirectoryParams, DownloadStartParams, DownloadStarted, DownloadStatusEvent,
-    Downloads, Event, IntervalSeconds, Members, MessageParams, Messages,
-    Method, QueryParams, RoomEventDto, RoomRef, SayParams, SearchResults,
-    Searches, Seconds, SessionLossEvent, SharesStatus, SlotsParams,
-    TransferRef, UploadInfoDto, Uploads, UserMessageDto, UserRef, UserResult,
+    Downloads, Event, IntervalSeconds, MemberStats, Members, MessageParams,
+    Messages, Method, QueryParams, RoomEventDto, RoomRef, SayParams,
+    SearchResults, Searches, Seconds, SessionLossEvent, SharesStatus,
+    SlotsParams, TransferRef, UploadInfoDto, Uploads, UserMessageDto, UserRef,
+    UserResult,
 };
 use schemars::{JsonSchema, SchemaGenerator, generate::SchemaSettings};
 use serde_json::{Value, json};
@@ -46,9 +47,10 @@ fn params_schema(method: Method, generator: &mut SchemaGenerator) -> Value {
         | Method::UploadCancel => schema_of::<TransferRef>(generator),
         Method::DownloadSetDir => schema_of::<DirectoryParams>(generator),
         Method::UploadSlots => schema_of::<SlotsParams>(generator),
-        Method::RoomJoin | Method::RoomLeave | Method::RoomMembers => {
-            schema_of::<RoomRef>(generator)
-        }
+        Method::RoomJoin
+        | Method::RoomLeave
+        | Method::RoomMembers
+        | Method::RoomMemberStats => schema_of::<RoomRef>(generator),
         Method::RoomSay => schema_of::<SayParams>(generator),
         Method::MessageSend => schema_of::<MessageParams>(generator),
         Method::BrowseUser | Method::UserRequest | Method::UserInfoOf => {
@@ -88,6 +90,7 @@ fn result_schema(method: Method, generator: &mut SchemaGenerator) -> Value {
         Method::UploadList => schema_of::<Uploads>(generator),
         Method::PrivilegesOwn => schema_of::<Seconds>(generator),
         Method::RoomMembers => schema_of::<Members>(generator),
+        Method::RoomMemberStats => schema_of::<MemberStats>(generator),
         Method::MessageHistory => schema_of::<Messages>(generator),
         Method::UserInfoOf => schema_of::<UserResult>(generator),
         Method::SharesStatusOf | Method::SharesSet | Method::SharesReindex => {
@@ -172,6 +175,9 @@ fn summary(method: Method) -> &'static str {
         Method::RoomLeave => "Leave a chat room.",
         Method::RoomSay => "Post a message to a room.",
         Method::RoomMembers => "Who is currently in a room.",
+        Method::RoomMemberStats => {
+            "What the server said about each member of a joined room."
+        }
         Method::MessageSend => "Send a private message.",
         Method::MessageHistory => {
             "Private messages the daemon collected, including while nobody was attached."

soulseek-rs/src/daemon/proto/dto.rs

@@ -7,7 +7,8 @@
 
 use serde::{Deserialize, Serialize};
 use soulseek_rs::types::{
-    Download, DownloadMetadata, UserPresence, UserStats, UserStatus,
+    Download, DownloadMetadata, RoomUserStats, UserPresence, UserStats,
+    UserStatus,
 };
 use soulseek_rs::{
     DownloadStatus, File, RoomEvent, RoomInfo, SearchResult, SessionLoss,
@@ -447,6 +448,58 @@ pub struct UserStatsDto {
     pub shared_folders: u32,
 }
 
+/// The inverse of [`UserStatus`]'s `Display`. An unrecognised word reads as
+/// offline, matching how the wire code is decoded.
+fn status_from_str(status: &str) -> UserStatus {
+    match status {
+        "online" => UserStatus::Online,
+        "away" => UserStatus::Away,
+        _ => UserStatus::Offline,
+    }
+}
+
+/// One member of a room, as the JoinRoom reply described them.
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
+#[cfg_attr(test, derive(schemars::JsonSchema))]
+pub struct RoomUserStatsDto {
+    pub username: String,
+    /// `online`, `away`, or `offline`.
+    pub status: String,
+    pub average_speed: u32,
+    pub shared_files: u32,
+    pub shared_folders: u32,
+    pub slots_free: u32,
+    pub country: Option<String>,
+}
+
+impl From<&RoomUserStats> for RoomUserStatsDto {
+    fn from(stats: &RoomUserStats) -> Self {
+        Self {
+            username: stats.username.clone(),
+            status: stats.status.to_string(),
+            average_speed: stats.average_speed,
+            shared_files: stats.shared_files,
+            shared_folders: stats.shared_folders,
+            slots_free: stats.slots_free,
+            country: stats.country.clone(),
+        }
+    }
+}
+
+impl From<RoomUserStatsDto> for RoomUserStats {
+    fn from(dto: RoomUserStatsDto) -> Self {
+        Self {
+            username: dto.username,
+            status: status_from_str(&dto.status),
+            average_speed: dto.average_speed,
+            shared_files: dto.shared_files,
+            shared_folders: dto.shared_folders,
+            slots_free: dto.slots_free,
+            country: dto.country,
+        }
+    }
+}
+
 /// Each half is `None` until its reply lands, so a consumer can tell "the
 /// server said offline" from "the server has not answered yet".
 #[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
@@ -480,11 +533,7 @@ impl From<UserInfoDto> for UserInfo {
     fn from(dto: UserInfoDto) -> Self {
         let mut info = Self::pending(dto.username);
         info.presence = dto.presence.map(|presence| UserPresence {
-            status: match presence.status.as_str() {
-                "online" => UserStatus::Online,
-                "away" => UserStatus::Away,
-                _ => UserStatus::Offline,
-            },
+            status: status_from_str(&presence.status),
             privileged: presence.privileged,
         });
         info.stats = dto.stats.map(|stats| UserStats {

soulseek-rs/src/daemon/proto/method.rs

@@ -1,5 +1,6 @@
 //! What each method takes and returns, and what each pushed event carries.
 
+use super::dto::RoomUserStatsDto;
 use super::dto::{
     DownloadDto, DownloadMetadataDto, DownloadStatusDto, SearchResultDto,
     SessionLossDto, SharedDirectoryDto, UploadInfoDto, UserInfoDto,
@@ -139,6 +140,13 @@ pub struct Members {
     pub users: Vec<String>,
 }
 
+/// What the server said about each member of a room when it was joined.
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
+#[cfg_attr(test, derive(schemars::JsonSchema))]
+pub struct MemberStats {
+    pub members: Vec<RoomUserStatsDto>,
+}
+
 /// One line of chat history. Unlike a live [`UserMessageDto`] this carries a
 /// direction, because a conversation the daemon collected includes what this
 /// account sent as well as what it received.

soulseek-rs/src/daemon/proto/mod.rs

@@ -101,6 +101,7 @@ wire_vocabulary! {
         RoomLeave => "room.leave",
         RoomSay => "room.say",
         RoomMembers => "room.members",
+        RoomMemberStats => "room.member_stats",
         MessageSend => "message.send",
         MessageHistory => "message.history",
         BrowseUser => "browse.user",

soulseek-rs/src/daemon/server/mod.rs

@@ -9,11 +9,12 @@ use super::hub::{Hub, PendingBrowses, PendingDownload};
 use super::proto::{
     Ack, AuthResult, CODE_APPLICATION, CODE_INVALID_PARAMS, ChatMessageDto,
     DaemonStatus, DirectoriesParams, DirectoryParams, DownloadDto,
-    DownloadStartParams, DownloadStarted, Downloads, IntervalSeconds, Members,
-    MessageParams, Messages, Method, OPENRPC, PROTOCOL_VERSION, QueryParams,
-    RoomRef, RpcError, SayParams, SearchResultDto, SearchResults,
-    SearchSummary, Searches, Seconds, SharesStatus, SlotsParams, TransferRef,
-    UploadInfoDto, Uploads, UserInfoDto, UserRef, UserResult,
+    DownloadStartParams, DownloadStarted, Downloads, IntervalSeconds,
+    MemberStats, Members, MessageParams, Messages, Method, OPENRPC,
+    PROTOCOL_VERSION, QueryParams, RoomRef, RoomUserStatsDto, RpcError,
+    SayParams, SearchResultDto, SearchResults, SearchSummary, Searches,
+    Seconds, SharesStatus, SlotsParams, TransferRef, UploadInfoDto, Uploads,
+    UserInfoDto, UserRef, UserResult,
 };
 use crate::api::SessionApi;
 use crate::output::Exit;
@@ -252,6 +253,18 @@ impl Daemon {
                 })
             }
 
+            Method::RoomMemberStats => {
+                let room: RoomRef = parse(params)?;
+                ok(MemberStats {
+                    members: self
+                        .session
+                        .room_member_stats(&room.room)
+                        .iter()
+                        .map(RoomUserStatsDto::from)
+                        .collect(),
+                })
+            }
+
             Method::MessageSend => {
                 let message: MessageParams = parse(params)?;
                 self.session
@@ -593,6 +606,29 @@ mod tests {
         );
     }
 
+    #[test]
+    fn member_stats_are_published_for_a_joined_room() {
+        let daemon = daemon_with_token("t");
+        let stats = daemon
+            .call(Method::RoomMemberStats, json!({ "room": STUB_ROOM }))
+            .expect("member stats");
+        assert_eq!(stats["members"][0]["username"], "alice");
+        assert_eq!(stats["members"][0]["status"], "online");
+        assert_eq!(stats["members"][0]["slots_free"], 1);
+        assert_eq!(stats["members"][0]["country"], "NL");
+    }
+
+    #[test]
+    fn a_room_that_was_never_joined_has_no_member_stats() {
+        // Empty, not an error: asking about a room this session is not in is
+        // an ordinary thing for a client to do.
+        let daemon = daemon_with_token("t");
+        let stats = daemon
+            .call(Method::RoomMemberStats, json!({ "room": "elsewhere" }))
+            .expect("member stats");
+        assert_eq!(stats["members"], json!([]));
+    }
+
     #[test]
     fn stop_is_recorded_so_the_daemon_can_wind_down() {
         let daemon = daemon_with_token("t");
@@ -605,8 +641,14 @@ mod tests {
 
     // A session that answers nothing: enough to exercise dispatch, parameter
     // validation, and the auth gate without a Soulseek server.
+    /// A session that answers nothing, except for one room whose members it
+    /// describes: the stats method is only meaningful if it can return
+    /// something for a joined room and nothing for any other.
     struct SilentSession;
 
+    /// The one room `SilentSession` claims to have joined.
+    const STUB_ROOM: &str = "jazz";
+
     fn daemon_with_token(token: &str) -> Daemon {
         Daemon {
             session: Arc::new(SilentSession),
@@ -764,6 +806,23 @@ mod tests {
         fn room_members(&self, _room: &str) -> Vec<String> {
             Vec::new()
         }
+        fn room_member_stats(
+            &self,
+            room: &str,
+        ) -> Vec<soulseek_rs::types::RoomUserStats> {
+            if room != STUB_ROOM {
+                return Vec::new();
+            }
+            vec![soulseek_rs::types::RoomUserStats {
+                username: "alice".to_string(),
+                status: soulseek_rs::types::UserStatus::Online,
+                average_speed: 1024,
+                shared_files: 20,
+                shared_folders: 3,
+                slots_free: 1,
+                country: Some("NL".to_string()),
+            }]
+        }
         fn take_room_events(&self) -> Vec<soulseek_rs::RoomEvent> {
             Vec::new()
         }