construct/include/ircd/m/feds.h

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2018 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_FEDS_H

/// Concurrent federation request interface. This fronts several of the m::v1
/// requests and conducts them to all servers in a room (e.g. m::room::origins)
/// at the same time. The hybrid control flow of this interface is best suited
/// to the real-world uses of these operations.
///
/// Each call in this interface is synchronous and will block the ircd::ctx
/// until it returns. The return value is the for_each-protocol result based on your
/// closure (if the closure ever returns false, the function also returns false).
///
/// The closure is invoke asynchronously as results come in. If the closure
/// returns false, the interface function will return immediately and all
/// pending requests will go out of scope and may be cancelled as per
/// ircd::server decides.
namespace ircd::m::feds
{
	struct opts;
	struct result;
	using closure = std::function<bool (const result &)>;

	bool head(const opts &, const closure &);
	bool event(const opts &, const closure &);
	bool state(const opts &, const closure &);
	bool backfill(const opts &, const closure &);
	bool version(const opts &, const closure &);
	bool perspective(const opts &, const closure &);
};

struct ircd::m::feds::result
{
	string_view origin;
	std::exception_ptr eptr;
	json::object object;
	json::array array;
};

struct ircd::m::feds::opts
{
	milliseconds timeout {20000L};
	m::room::id room_id;
	m::event::id event_id;
	m::user::id user_id;
	string_view arg[4];  // misc argv
	uint64_t argi[4];    // misc integer argv
};