aboutsummaryrefslogtreecommitdiffstats
path: root/net/http/server.lua
blob: 0682d6ed85e66b441701c5ac2a046eae389d43f0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406

local t_insert, t_remove, t_concat = table.insert, table.remove, table.concat;
local parser_new = require "net.http.parser".new;
local events = require "util.events".new();
local addserver = require "net.server".addserver;
local log = require "util.logger".init("http.server");
local os_date = os.date;
local pairs = pairs;
local s_upper = string.upper;
local setmetatable = setmetatable;
local xpcall = require "util.xpcall".xpcall;
local traceback = debug.traceback;
local tostring = tostring;
local cache = require "util.cache";
local codes = require "net.http.codes";
local blocksize = 2^16;

local _M = {};

local sessions = {};
local incomplete = {};
local listener = {};
local hosts = {};
local default_host;
local options = {};

local function is_wildcard_event(event)
	return event:sub(-2, -1) == "/*";
end
local function is_wildcard_match(wildcard_event, event)
	return wildcard_event:sub(1, -2) == event:sub(1, #wildcard_event-1);
end

local _handlers = events._handlers;
local recent_wildcard_events = cache.new(10000, function (key, value) -- luacheck: ignore 212/value
	rawset(_handlers, key, nil);
end);

local event_map = events._event_map;
setmetatable(events._handlers, {
	-- Called when firing an event that doesn't exist (but may match a wildcard handler)
	__index = function (handlers, curr_event)
		if is_wildcard_event(curr_event) then return; end -- Wildcard events cannot be fired
		-- Find all handlers that could match this event, sort them
		-- and then put the array into handlers[curr_event] (and return it)
		local matching_handlers_set = {};
		local handlers_array = {};
		for event, handlers_set in pairs(event_map) do
			if event == curr_event or
			is_wildcard_event(event) and is_wildcard_match(event, curr_event) then
				for handler, priority in pairs(handlers_set) do
					matching_handlers_set[handler] = { (select(2, event:gsub("/", "%1"))), is_wildcard_event(event) and 0 or 1, priority };
					table.insert(handlers_array, handler);
				end
			end
		end
		if #handlers_array > 0 then
			table.sort(handlers_array, function(b, a)
				local a_score, b_score = matching_handlers_set[a], matching_handlers_set[b];
				for i = 1, #a_score do
					if a_score[i] ~= b_score[i] then -- If equal, compare next score value
						return a_score[i] < b_score[i];
					end
				end
				return false;
			end);
		else
			handlers_array = false;
		end
		rawset(handlers, curr_event, handlers_array);
		if not event_map[curr_event] then -- Only wildcard handlers match, if any
			recent_wildcard_events:set(curr_event, true);
		end
		return handlers_array;
	end;
	__newindex = function (handlers, curr_event, handlers_array)
		if handlers_array == nil
		and is_wildcard_event(curr_event) then
			-- Invalidate the indexes of all matching events
			for event in pairs(handlers) do
				if is_wildcard_match(curr_event, event) then
					handlers[event] = nil;
				end
			end
		end
		rawset(handlers, curr_event, handlers_array);
	end;
});

local handle_request;

local last_err;
local function _traceback_handler(err) last_err = err; log("error", "Traceback[httpserver]: %s", traceback(tostring(err), 2)); end
events.add_handler("http-error", function (error)
	return "Error processing request: "..codes[error.code]..". Check your error log for more information.";
end, -1);

function listener.onconnect(conn)
	local secure = conn:ssl() and true or nil;
	local pending = {};
	local waiting = false;
	local function process_next()
		if waiting then return; end -- log("debug", "can't process_next, waiting");
		waiting = true;
		while sessions[conn] and #pending > 0 do
			local request = t_remove(pending);
			--log("debug", "process_next: %s", request.path);
			if not xpcall(handle_request, _traceback_handler, conn, request, process_next) then
				conn:write("HTTP/1.0 500 Internal Server Error\r\n\r\n"..events.fire_event("http-error", { code = 500, private_message = last_err }));
				conn:close();
			end
		end
		--log("debug", "ready for more");
		waiting = false;
	end
	local function success_cb(request)
		--log("debug", "success_cb: %s", request.path);
		if waiting then
			log("error", "http connection handler is not reentrant: %s", request.path);
			assert(false, "http connection handler is not reentrant");
		end
		request.secure = secure;
		t_insert(pending, request);
		process_next();
	end
	local function error_cb(err)
		log("debug", "error_cb: %s", err or "<nil>");
		-- FIXME don't close immediately, wait until we process current stuff
		-- FIXME if err, send off a bad-request response
		sessions[conn] = nil;
		conn:close();
	end
	local function options_cb()
		return options;
	end
	sessions[conn] = parser_new(success_cb, error_cb, "server", options_cb);
end

function listener.ondisconnect(conn)
	local open_response = conn._http_open_response;
	if open_response and open_response.on_destroy then
		open_response.finished = true;
		open_response:on_destroy();
	end
	incomplete[conn] = nil;
	sessions[conn] = nil;
end

function listener.ondetach(conn)
	sessions[conn] = nil;
	incomplete[conn] = nil;
end

function listener.onincoming(conn, data)
	sessions[conn]:feed(data);
end

function listener.ondrain(conn)
	local response = incomplete[conn];
	if response and response._send_more then
		response._send_more();
	end
end

local headerfix = setmetatable({}, {
	__index = function(t, k)
		local v = "\r\n"..k:gsub("_", "-"):gsub("%f[%w].", s_upper)..": ";
		t[k] = v;
		return v;
	end
});

local function handle_result(request, response, result)
	if result == nil then
		result = 404;
	end

	if result == true then
		return;
	end

	local body;
	local result_type = type(result);
	if result_type == "number" then
		response.status_code = result;
		if result >= 400 then
			body = events.fire_event("http-error", { request = request, response = response, code = result });
		end
	elseif result_type == "string" then
		body = result;
	elseif result_type == "table" then
		for k, v in pairs(result) do
			if k ~= "headers" then
				response[k] = v;
			else
				for header_name, header_value in pairs(v) do
					response.headers[header_name] = header_value;
				end
			end
		end
	end
	return response:send(body);
end

function _M.hijack_response(response, listener) -- luacheck: ignore
	error("TODO");
end
function handle_request(conn, request, finish_cb)
	--log("debug", "handler: %s", request.path);
	local headers = {};
	for k,v in pairs(request.headers) do headers[k:gsub("-", "_")] = v; end
	request.headers = headers;
	request.conn = conn;

	local date_header = os_date('!%a, %d %b %Y %H:%M:%S GMT'); -- FIXME use
	local conn_header = request.headers.connection;
	conn_header = conn_header and ","..conn_header:gsub("[ \t]", ""):lower().."," or ""
	local httpversion = request.httpversion
	local persistent = conn_header:find(",keep-alive,", 1, true)
		or (httpversion == "1.1" and not conn_header:find(",close,", 1, true));

	local response_conn_header;
	if persistent then
		response_conn_header = "Keep-Alive";
	else
		response_conn_header = httpversion == "1.1" and "close" or nil
	end

	local is_head_request = request.method == "HEAD";

	local response = {
		request = request;
		is_head_request = is_head_request;
		status_code = 200;
		headers = { date = date_header, connection = response_conn_header };
		persistent = persistent;
		conn = conn;
		send = _M.send_response;
		send_file = _M.send_file;
		done = _M.finish_response;
		finish_cb = finish_cb;
	};
	conn._http_open_response = response;

	local host = (request.headers.host or ""):match("[^:]+");

	-- Some sanity checking
	local err_code, err;
	if not request.path then
		err_code, err = 400, "Invalid path";
	end

	if err then
		response.status_code = err_code;
		response:send(events.fire_event("http-error", { code = err_code, message = err, response = response }));
		return;
	end

	local global_event = request.method.." "..request.path:match("[^?]*");

	local payload = { request = request, response = response };
	log("debug", "Firing event: %s", global_event);
	local result = events.fire_event(global_event, payload);
	if result == nil and is_head_request then
		local global_head_event = "GET "..request.path:match("[^?]*");
		log("debug", "Firing event: %s", global_head_event);
		result = events.fire_event(global_head_event, payload);
	end
	if result == nil then
		if not hosts[host] then
			if hosts[default_host] then
				host = default_host;
			elseif host then
				err_code, err = 404, "Unknown host: "..host;
			else
				err_code, err = 400, "Missing or invalid 'Host' header";
			end
		end

		if err then
			response.status_code = err_code;
			response:send(events.fire_event("http-error", { code = err_code, message = err, response = response }));
			return;
		end

		local host_event = request.method.." "..host..request.path:match("[^?]*");
		log("debug", "Firing event: %s", host_event);
		result = events.fire_event(host_event, payload);

		if result == nil and is_head_request then
			local host_head_event = "GET "..host..request.path:match("[^?]*");
			log("debug", "Firing event: %s", host_head_event);
			result = events.fire_event(host_head_event, payload);
		end
	end

	return handle_result(request, response, result);
end

local function prepare_header(response)
	local status_line = "HTTP/"..response.request.httpversion.." "..(response.status or codes[response.status_code]);
	local headers = response.headers;
	local output = { status_line };
	for k,v in pairs(headers) do
		t_insert(output, headerfix[k]..v);
	end
	t_insert(output, "\r\n\r\n");
	return output;
end
_M.prepare_header = prepare_header;
function _M.send_head_response(response)
	if response.finished then return; end
	local output = prepare_header(response);
	response.conn:write(t_concat(output));
	response:done();
end
function _M.send_response(response, body)
	if response.finished then return; end
	body = body or response.body or "";
	response.headers.content_length = ("%d"):format(#body);
	if response.is_head_request then
		return _M.send_head_response(response)
	end
	local output = prepare_header(response);
	t_insert(output, body);
	response.conn:write(t_concat(output));
	response:done();
end
function _M.send_file(response, f)
	if response.is_head_request then
		if f.close then f:close(); end
		return _M.send_head_response(response);
	end
	if response.finished then return; end
	local chunked = not response.headers.content_length;
	if chunked then response.headers.transfer_encoding = "chunked"; end
	incomplete[response.conn] = response;
	response._send_more = function ()
		if response.finished then
			incomplete[response.conn] = nil;
			return;
		end
		local chunk = f:read(blocksize);
		if chunk then
			if chunked then
				chunk = ("%x\r\n%s\r\n"):format(#chunk, chunk);
			end
			-- io.write("."); io.flush();
			response.conn:write(chunk);
		else
			if chunked then
				response.conn:write("0\r\n\r\n");
			end
			-- io.write("\n");
			if f.close then f:close(); end
			incomplete[response.conn] = nil;
			return response:done();
		end
	end
	response.conn:write(t_concat(prepare_header(response)));
	return true;
end
function _M.finish_response(response)
	if response.finished then return; end
	response.finished = true;
	response.conn._http_open_response = nil;
	if response.on_destroy then
		response:on_destroy();
		response.on_destroy = nil;
	end
	if response.persistent then
		response:finish_cb();
	else
		response.conn:close();
	end
end
function _M.add_handler(event, handler, priority)
	events.add_handler(event, handler, priority);
end
function _M.remove_handler(event, handler)
	events.remove_handler(event, handler);
end

function _M.listen_on(port, interface, ssl)
	return addserver(interface or "*", port, listener, "*a", ssl);
end
function _M.add_host(host)
	hosts[host] = true;
end
function _M.remove_host(host)
	hosts[host] = nil;
end
function _M.set_default_host(host)
	default_host = host;
end
function _M.fire_event(event, ...)
	return events.fire_event(event, ...);
end
function _M.set_option(name, value)
	options[name] = value;
end

_M.listener = listener;
_M.codes = codes;
_M._events = events;
return _M;