ircd:Ⓜ️:trace: Add interface for the trace.

include/ircd/m/m.h

@@ -66,6 +66,7 @@ namespace ircd::m
 #include "txn.h"
 #include "relates.h"
 #include "room/room.h"
+#include "trace.h"
 #include "user/user.h"
 #include "users.h"
 #include "rooms.h"

include/ircd/m/trace.h

@@ -0,0 +1,23 @@
+// Matrix Construct
+//
+// Copyright (C) Matrix Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2022 Jason Volk <jason@zemos.net>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice is present in all copies. The
+// full license for this software is available in the LICENSE file.
+
+#pragma once
+#define HAVE_IRCD_M_TRACE_H
+
+namespace ircd::m::trace
+{
+	using closure = util::closure_bool
+	<
+		std::function,
+		const event::idx &, const uint64_t &, const m::room::message &
+	>;
+
+	bool for_each(const event::idx &, const closure &);
+}

matrix/Makefile.am

@@ -179,6 +179,7 @@ libircd_matrix_la_SOURCES += rooms.cc
 libircd_matrix_la_SOURCES += membership.cc
 libircd_matrix_la_SOURCES += rooms_summary.cc
 libircd_matrix_la_SOURCES += sync.cc
+libircd_matrix_la_SOURCES += trace.cc
 libircd_matrix_la_SOURCES += typing.cc
 libircd_matrix_la_SOURCES += users.cc
 libircd_matrix_la_SOURCES += users_servers.cc

matrix/trace.cc

@@ -0,0 +1,81 @@
+// Matrix Construct
+//
+// Copyright (C) The Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2022 Jason Volk <jason@zemos.net>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice is present in all copies. The
+// full license for this software is available in the LICENSE file.
+
+bool
+ircd::m::trace::for_each(const event::idx &event_idx,
+                         const closure &closure)
+{
+	event::fetch event
+	{
+		std::nothrow, event_idx
+	};
+
+	if(!event.valid)
+		return true;
+
+	if(redacted(event))
+		return true;
+
+	room::messages messages
+	{
+		room::id{json::get<"room_id"_>(event)},
+		{
+			json::get<"depth"_>(event), -1L
+		}
+	};
+
+	bool ret(true), loop; do
+	{
+		loop = false;
+		messages.for_each([&closure, &event, &messages, &loop, &ret]
+		(const room::message &msg, const int64_t &depth, const event::idx &event_idx)
+		{
+			// Ignore messages at the same depth as the initial
+			if(event.event_idx != event_idx && depth == json::get<"depth"_>(event))
+				return true;
+
+			// Call user; check if they want to break iteration
+			if(!(ret = closure(event_idx, depth, msg)))
+				return false;
+
+			const auto reply_to_id
+			{
+				msg.reply_to_event()
+			};
+
+			// If this is not a reply continue to the prior message.
+			if(!reply_to_id)
+				return true;
+
+			// If we don't have the message being replied to, break here
+			if(!seek(std::nothrow, event, reply_to_id))
+				return false;
+
+			// The message replied to was redacted, break here.
+			if(redacted(event))
+				return false;
+
+			// Jump to the message being replied to
+			messages =
+			{
+				room::id{json::get<"room_id"_>(event)},
+				{
+					json::get<"depth"_>(event), -1L
+				}
+			};
+
+			loop = true;
+			return false;
+		});
+	}
+	while(ret && loop);
+
+	return ret;
+}

modules/console.cc

@@ -8876,6 +8876,56 @@ console_cmd__event__relates(opt &out, const string_view &line)
 	return true;
 }
 
+bool
+console_cmd__event__trace(opt &out, const string_view &line)
+{
+	const params param{line, " ",
+	{
+		"event_id", "limit"
+	}};
+
+	const m::event::id &event_id
+	{
+		param.at("event_id")
+	};
+
+	ssize_t limit
+	{
+		param.at("limit", 48L)
+	};
+
+	const auto event_idx
+	{
+		index(event_id)
+	};
+
+	m::event::fetch event;
+	m::trace::for_each(event_idx, [&out, &limit, &event]
+	(const m::event::idx &event_idx, const uint64_t &depth, const m::room::message &msg)
+	{
+		if(!seek(std::nothrow, event, event_idx))
+			return true;
+
+		json::get<"content"_>(event) = msg.source;
+		const m::pretty_opts opts
+		{
+			.event_idx = event_idx,
+			.show_origin_server_ts = false,
+			.show_origin_server_ts_ago = true,
+			.show_event_id = false,
+			.show_state_key = false,
+			.show_msgtype = false,
+		};
+
+		out
+		<< pretty_msgline(event, opts)
+		<< std::endl;
+		return --limit > 0;
+	});
+
+	return true;
+}
+
 //
 // eval
 //