Provide reason for player leaving

Expose the reason for why a player is leaving a server in playerEvent.

packages/lib/link/messages.js

@@ -1284,10 +1284,12 @@ messages.playerEvent = new Event({
 	type: "player_event",
 	links: ["instance-slave", "slave-master"],
 	forwardTo: "master",
+	eventRequired: ["instance_id", "type", "name"],
 	eventProperties: {
 		"instance_id": { type: "integer" },
 		"type": { type: "string", enum: ["join", "leave"] },
 		"name": { type: "string" },
+		"reason": { type: "string" },
 	},
 });
 

packages/lib/plugin.js

@@ -208,6 +208,9 @@ class BaseInstancePlugin {
 	 * @param {Object} event - Information about the event.
 	 * @param {string} event.type - Either "join" or "leave".
 	 * @param {string} event.name - Name of the player that joined/left.
+	 * @param {string=} event.reason -
+	 *     Only present for type "leave". Reason for player leaving the
+	 *     game, one of the possible reasons in defines.disconnect_reason.
 	 */
 	async onPlayerEvent(event) { }
 
@@ -500,6 +503,9 @@ class BaseMasterPlugin {
 	 * @param {Object} event - Information about the event.
 	 * @param {string} event.type - Either "join" or "leave".
 	 * @param {string} event.name - Name of the player that joined/left.
+	 * @param {string=} event.reason -
+	 *     Only present for type "leave". Reason for player leaving the
+	 *     game, one of the possible reasons in defines.disconnect_reason.
 	 */
 	async onPlayerEvent(instance, event) { }
 

packages/slave/modules/clusterio/impl.lua

@@ -28,9 +28,18 @@ impl.events[defines.events.on_player_joined_game] = function(event)
 	api.send_json("player_event", { type = "join", name = player.name })
 end
 
+local disconnect_reason_name = {}
+for name, i in pairs(defines.disconnect_reason) do
+	disconnect_reason_name[i] = name
+end
+
 impl.events[defines.events.on_player_left_game] = function(event)
 	local player = game.players[event.player_index]
-	api.send_json("player_event", { type = "leave", name = player.name })
+	api.send_json("player_event", {
+		type = "leave",
+		name = player.name,
+		reason = disconnect_reason_name[event.reason],
+	})
 end
 
 -- Internal API

packages/slave/src/Instance.js

@@ -250,7 +250,7 @@ class Instance extends libLink.Link {
 			if (event.type === "join") {
 				this._recordPlayerJoin(event.name);
 			} else if (event.type === "leave") {
-				this._recordPlayerLeave(event.name);
+				this._recordPlayerLeave(event.name, event.reason);
 			}
 		});
 
@@ -264,6 +264,9 @@ class Instance extends libLink.Link {
 		 *     Unix timestamp in ms the player was last seen leaving this
 		 *     instance.  Not present if player has yet to leave after first
 		 *     time joining.
+		 * @property {string=} lastLeaveReason -
+		 *     Reason the player was last seen leaving with.  Not present if
+		 *     player has yet to leave after first time joining.
 		 * @property {number} joinCount -
 		 *     Count of the number of times this player has been seen
 		 *     joining this server.
@@ -297,7 +300,12 @@ class Instance extends libLink.Link {
 			if (parsed.action === "JOIN") {
 				this._recordPlayerJoin(name);
 			} else if (["LEAVE", "KICK", "BAN"].includes(parsed.action)) {
-				this._recordPlayerLeave(name);
+				let reason = {
+					"LEAVE": "quit",
+					"KICK": "kicked",
+					"BAN": "banned",
+				}[parsed.action];
+				this._recordPlayerLeave(name, reason);
 			}
 		});
 
@@ -322,7 +330,7 @@ class Instance extends libLink.Link {
 			this.playersOnline.forEach(player => joined.delete(player));
 
 			for (let player of left) {
-				this._recordPlayerLeave(player);
+				this._recordPlayerLeave(player, "quit");
 			}
 
 			// Missing join messages is not supposed to happen.
@@ -358,13 +366,14 @@ class Instance extends libLink.Link {
 		libPlugin.invokeHook(this.plugins, "onPlayerEvent", event);
 	}
 
-	_recordPlayerLeave(name) {
+	_recordPlayerLeave(name, reason) {
 		if (!this.playersOnline.delete(name)) {
 			return;
 		}
 
 		let stats = this.playerStats.get(name);
 		stats.lastLeaveAt = Date.now();
+		stats.lastLeaveReason = reason;
 		stats.onlineTimeMs += stats.lastLeaveAt - stats.lastJoinAt;
 		this._hadPlayersOnline = true;
 
@@ -372,6 +381,7 @@ class Instance extends libLink.Link {
 			instance_id: this.id,
 			type: "leave",
 			name,
+			reason,
 		};
 		libLink.messages.playerEvent.send(this, event);
 		libPlugin.invokeHook(this.plugins, "onPlayerEvent", event);

test/slave/Instance.js

@@ -89,21 +89,21 @@ describe("class Instance", function() {
 
 		it("should send player_event", function() {
 			instance._recordPlayerJoin("player");
-			instance._recordPlayerLeave("player");
+			instance._recordPlayerLeave("player", "quit");
 			assert.deepEqual(
 				connector.sentMessages[1],
 				{
 					seq: 2,
 					type: "player_event_event",
-					data: { type: "leave", instance_id: instance.id, name: "player" },
+					data: { type: "leave", instance_id: instance.id, name: "player", reason: "quit" },
 				},
 			);
 		});
 
 		it("should be idempotent", function() {
 			instance._recordPlayerJoin("player");
-			instance._recordPlayerLeave("player");
-			instance._recordPlayerLeave("player");
+			instance._recordPlayerLeave("player", "quit");
+			instance._recordPlayerLeave("player", "quit");
 			assert(!instance.playersOnline.has("player"), "player was not removed");
 			assert.equal(connector.sentMessages.length, 2);
 		});
@@ -148,7 +148,7 @@ describe("class Instance", function() {
 				{
 					seq: 2,
 					type: "player_event_event",
-					data: { type: "leave", instance_id: instance.id, name: "player" },
+					data: { type: "leave", instance_id: instance.id, name: "player", reason: "quit" },
 				},
 			);
 		});