Line data Source code
1 : #ifndef HEADER_fd_src_ballet_http_fd_http_server_h
2 : #define HEADER_fd_src_ballet_http_fd_http_server_h
3 :
4 : /* An fd_http_server is a WebSocket capable HTTP server designed to
5 : stream output messages quickly to many connected clients, where each
6 : output message can go to many (and in some cases all) clients.
7 :
8 : The primary use case is for serving ongoing RPC data to RPC
9 : subscribers, but it also serves a WebSocket stream for browser
10 : clients to show the GUI.
11 :
12 : The server does not allocate and has a built in allocation strategy
13 : and memory region for outgoing messages which the caller should use.
14 : HTTP repsonse bodies and WebSocket frames are placed into an outgoing
15 : ring buffer, wrapping around when reaching the end, and the server
16 : will automatically evict slow clients that do not read their messages
17 : in time and would be overwriten when the buffer has wrapped fully
18 : around.
19 :
20 : Using the outgoing ring has two steps,
21 :
22 : (1) Stage data into the ring with fd_http_server_printf and
23 : fd_http_server_memcpy functions.
24 : (2) Send the staged data to clients with fd_http_server_send and
25 : fd_http_server_oring_broadcast.
26 :
27 : The server is designed to be used in a single threaded event loop and
28 : run within a tile. The caller should call fd_http_server_poll as
29 : frequently as possible to service connections and make forward
30 : progress. */
31 :
32 : #include "../../util/fd_util_base.h"
33 :
34 30 : #define FD_HTTP_SERVER_ALIGN (128UL)
35 :
36 0 : #define FD_HTTP_SERVER_METHOD_GET (0)
37 0 : #define FD_HTTP_SERVER_METHOD_POST (1)
38 0 : #define FD_HTTP_SERVER_METHOD_OPTIONS (2)
39 0 : #define FD_HTTP_SERVER_METHOD_PUT (3)
40 :
41 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_OK ( -1)
42 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_EVICTED ( -2)
43 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_TOO_SLOW ( -3)
44 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_EXPECTED_EOF ( -4)
45 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_PEER_RESET ( -5)
46 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_LARGE_REQUEST ( -6)
47 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_BAD_REQUEST ( -7)
48 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_MISSING_CONENT_LENGTH_HEADER ( -8)
49 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_UNKNOWN_METHOD ( -9)
50 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_PATH_TOO_LONG (-10)
51 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_BAD_KEY (-11)
52 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_UNEXPECTED_VERSION (-12)
53 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_MISSING_KEY_HEADER (-13)
54 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_MISSING_VERSION_HEADER (-14)
55 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_BAD_MASK (-15)
56 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_UNKNOWN_OPCODE (-16)
57 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_OVERSIZE_FRAME (-17)
58 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_CLIENT_TOO_SLOW (-18)
59 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_MISSING_UPGRADE (-19)
60 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_EXPECTED_CONT_OPCODE (-20)
61 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_EXPECTED_TEXT_OPCODE (-21)
62 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_CONTROL_FRAME_TOO_LARGE (-22)
63 0 : #define FD_HTTP_SERVER_CONNECTION_CLOSE_WS_CHANGED_OPCODE (-23)
64 :
65 : /* Given a FD_HTTP_SERVER_CONNECTION_CLOSE_* reason code, a reason that
66 : a HTTP connection a client was closed, produce a human readable
67 : string describing the reason. */
68 :
69 : FD_FN_CONST char const *
70 : fd_http_server_connection_close_reason_str( int reason );
71 :
72 : /* Given a FD_HTTP_SERVER_METHOD_* code, produce the string for that
73 : method. */
74 :
75 : FD_FN_CONST char const *
76 : fd_http_server_method_str( uchar method );
77 :
78 : /* Parameters needed for constructing an HTTP server. */
79 :
80 : struct fd_http_server_params {
81 : ulong max_connection_cnt; /* Maximum number of concurrent HTTP/1.1 connections open. Connections are not persistent and will be closed after one request is served */
82 : ulong max_ws_connection_cnt; /* Maximum number of concurrent websocket connections open */
83 : ulong max_request_len; /* Maximum total length of an HTTP request, including the terminating \r\n\r\n and any body in the case of a POST */
84 : ulong max_ws_recv_frame_len; /* Maximum size of an incoming websocket frame from the client. Must be >= max_request_len */
85 : ulong max_ws_send_frame_cnt; /* Maximum number of outgoing websocket frames that can be queued before the client is disconnected */
86 : ulong outgoing_buffer_sz; /* Size of the outgoing data ring, which is used to stage outgoing HTTP response bodies and WebSocket frames */
87 : };
88 :
89 : typedef struct fd_http_server_params fd_http_server_params_t;
90 :
91 : struct fd_http_server_request {
92 : ulong connection_id; /* Unique identifier for the connection. In [0, max_connection_cnt). The connection ID is a unique identifier for the lifetime of the connection, and will be
93 : provided to close to indicate that the connection is closed. After a connection is closed the ID may be recycled */
94 :
95 : uchar method; /* One of FD_HTTP_SERVER_METHOD_* indicating what the method of the request is */
96 : char const * path; /* The NUL termoinated path component of the request. Not sanitized and may contain arbitrary content. Path is the full HTTP path of the request, for example
97 : "/img/monkeys/gorilla.jpg" */
98 :
99 : void * ctx; /* The user provided context pointer passed when constructing the HTTP server */
100 :
101 : struct {
102 : char const * content_type; /* The NUL terminated value of the Content-Type header of the request. Not sanitized and may contain arbitrary content. May be NULL if the header was not present */
103 : char const * accept_encoding; /* The NUL terminated value of the Accept-Encoding header of the request. Not sanitized and may contain arbitrary content. May be NULL if the header was not present */
104 : int upgrade_websocket; /* True if the client has provided an `Upgrade: websocket` header, valid `Sec-WebSocket-Key` and supported `Sec-Websocket-Version`, indicating that the
105 : responder should upgrade the connection to a WebSocket by setting `upgrade_websocket` to 1 in the response */
106 : } headers;
107 :
108 : union {
109 : struct {
110 : uchar const * body; /* The body of the HTTP request. The body is byte data, might have internal NUL characters, and may not be NUL terminated */
111 : ulong body_len; /* The length of the body of the HTTP request */
112 : } post;
113 : };
114 : };
115 :
116 : typedef struct fd_http_server_request fd_http_server_request_t;
117 :
118 : /* A response issued by the server handler function to an HTTP request.
119 :
120 : The handler should typically create response bodies via. the HTTP
121 : server functions like fd_http_server_printf. This allows the server
122 : to manage buffer lifetimes and ensure high performance. If using
123 : the server buffers, the handler should not set a static_body or
124 : static_body_len, and should instead use fd_http_server_stage_body
125 : to snap off the staging buffer contents into the body.
126 :
127 : In certain cases, it is desirable to send static content where the
128 : lifetime of the buffer is known to outlive the HTTP server. In
129 : that case, you can set body_static to non-NULL and body_len_static
130 : to the length of the body payload, and the server will send this
131 : data instead of the staged data instead.
132 :
133 : status is an HTTP status code. If status is not 200, the response
134 : body is ignored and the server will send an empty response.
135 :
136 : If upgrade_websocket is true, the connection will be upgraded to a
137 : websocket, after which the handler will begin receiving websocket
138 : frames. */
139 :
140 : struct fd_http_server_response {
141 : ulong status; /* Status code of the HTTP response */
142 : int upgrade_websocket; /* 1 if we should send a websocket upgrade response */
143 :
144 : char const * content_type; /* Content-Type to set in the HTTP response */
145 : char const * cache_control; /* Cache-Control to set in the HTTP response */
146 : char const * content_encoding; /* Content-Encoding to set in the HTTP response */
147 :
148 : char const * access_control_allow_origin;
149 : char const * access_control_allow_methods;
150 : char const * access_control_allow_headers;
151 : ulong access_control_max_age;
152 :
153 : uchar const * static_body; /* Response body to send. Lifetime of response data must outlive the entire HTTP server. */
154 : ulong static_body_len; /* Length of the response body */
155 :
156 : ulong _body_off; /* Internal use only. Offset into the outgoing buffer where the body starts */
157 : ulong _body_len; /* Internal use only. Length of the body in the outgoing buffer */
158 : };
159 :
160 : typedef struct fd_http_server_response fd_http_server_response_t;
161 :
162 : struct fd_http_server_callbacks {
163 : /* Handle an incoming HTTP request. The callback must be provided
164 : and is assumed to be non-NULL. request is a representation of
165 : the incoming HTTP request. The callback should return a response
166 : which will be sent to the client. */
167 :
168 : fd_http_server_response_t ( * request )( fd_http_server_request_t const * request );
169 :
170 : /* Called when a regular HTTP connection is established. Called
171 : immediately after the connection is accepted. sockfd is the file
172 : descriptor of the socket. ctx is the user provided context pointer
173 : provided when constructing the HTTP server. The open callback can
174 : be NULL in which case the callback will not be invoked. */
175 :
176 : void ( * open )( ulong conn_id, int sockfd, void * ctx );
177 :
178 : /* Close an HTTP request. This is called back once all the data has
179 : been sent to the HTTP client, or an error condition occurs, or the
180 : caller force closes the connection by calling close. If a
181 : connection is upgraded to a WebSocket connection, a close event is
182 : first sent once the HTTP upgrade response is sent, before a ws_open
183 : event is sent. Close is not called when a WebSocket connection is
184 : closed, instead ws_close is called. reason is one of
185 : FD_HTTP_SERVER_CONNECTION_CLOSE_* indicating why the connection is
186 : being closed. ctx is the user provided context pointer provided
187 : when constructing the HTTP server. The close callback can be NULL
188 : in which case the callback will not be invoked. */
189 :
190 : void ( * close )( ulong conn_id, int reason, void * ctx );
191 :
192 : /* Called when a WebSocket is opened. ws_conn_id in [0,
193 : max_ws_connection_cnt). Connection IDs are recycled as WebSocket
194 : connections are closed. Connection IDs overlap with regular
195 : (non-WebSocket) connection IDs, but are in a distinct namespace,
196 : and WebSocket connection 0 is different from regular connection 0.
197 : ctx is the user provided context pointer provided when constructing
198 : the HTTP server. */
199 :
200 : void ( * ws_open )( ulong ws_conn_id, void * ctx );
201 :
202 : /* Called when a WebSocket message is received on the connection.
203 : data is the message data, and data_len is the length of the message
204 : data. ctx is the user provided context pointer provided when
205 : constructing the HTTP server. The data provided is valid only
206 : until the callback returns, and the buffer will be recycled again
207 : immediately. data_len is in [0, max_ws_recv_frame_len). */
208 :
209 : void ( * ws_message )( ulong ws_conn_id, uchar const * data, ulong data_len, void * ctx );
210 :
211 : /* Called when a WebSocket connection is closed. reason is one of
212 : FD_HTTP_SERVER_CONNECTION_CLOSE_* indicating why the connection was
213 : closed. ctx is the user provided context pointer provided when
214 : constructing the HTTP server. Typical reasons for closing the
215 : WebSocket include the peer disconnecting or timing out, or being
216 : evicted to make space for a new incoming connection. Also called
217 : back when the user of the API forcibly closes a connection by
218 : calling ws_close. */
219 :
220 : void ( * ws_close )( ulong ws_conn_id, int reason, void * ctx );
221 : };
222 :
223 : typedef struct fd_http_server_callbacks fd_http_server_callbacks_t;
224 :
225 : struct fd_http_server_private;
226 : typedef struct fd_http_server_private fd_http_server_t;
227 :
228 : FD_PROTOTYPES_BEGIN
229 :
230 : /* fd_http_server_{align,footprint} give the needed alignment and
231 : footprint of a memory region suitable to hold an http server.
232 :
233 : fd_http_server_new formats memory region with suitable alignment and
234 : footprint suitable for holding a http server state. Assumes shmem
235 : points on the caller to the first byte of the memory region owned by
236 : the caller to use. Returns shmem on success and NULL on failure
237 : (logs details). The memory region will be owned by the state on
238 : successful return. The caller is not joined on return.
239 :
240 : fd_http_server_join joins the caller to a http server state. Assumes
241 : shhttp points to the first byte of the memory region holding the
242 : state. Returns a local handle to the join on success (this is
243 : not necessarily a simple cast of the address) and NULL on failure
244 : (logs details).
245 :
246 : fd_http_server_leave leaves the caller's current local join to a http
247 : server state. Returns a pointer to the memory region holding the
248 : state on success (this is not necessarily a simple cast of the
249 : address) and NULL on failure (logs details). The caller is not
250 : joined on successful return.
251 :
252 : fd_http_server_delete unformats a memory region that holds a http
253 : server state. Assumes shhttp points on the caller to the first
254 : byte of the memory region holding the state and that nobody is
255 : joined. Returns a pointer to the memory region on success and NULL
256 : on failure (logs details). The caller has ownership of the memory
257 : region on successful return. */
258 :
259 : FD_FN_CONST ulong
260 : fd_http_server_align( void );
261 :
262 : FD_FN_CONST ulong
263 : fd_http_server_footprint( fd_http_server_params_t params );
264 :
265 : void *
266 : fd_http_server_new( void * shmem,
267 : fd_http_server_params_t params,
268 : fd_http_server_callbacks_t callbacks,
269 : void * callback_ctx );
270 :
271 : fd_http_server_t *
272 : fd_http_server_join( void * shhttp );
273 :
274 : void *
275 : fd_http_server_leave( fd_http_server_t * http );
276 :
277 : void *
278 : fd_http_server_delete( void * shhttp );
279 :
280 : /* fd_http_server_fd returns the file descriptor of the server. The
281 : file descriptor is used to poll for incoming connections and data
282 : on the server. */
283 :
284 : int
285 : fd_http_server_fd( fd_http_server_t * http );
286 :
287 : fd_http_server_t *
288 : fd_http_server_listen( fd_http_server_t * http,
289 : uint address,
290 : ushort port );
291 :
292 : /* Close an active connection. The connection ID must be an open
293 : open connection in [0, max_connection_cnt). The connection will
294 : be forcibly (ungracefully) terminated. The connection ID is released
295 : and should not be used again, as it may be recycled for a future
296 : connection. If a close callback has been provided to the http
297 : server, it will be invoked with the reason provided. */
298 :
299 : void
300 : fd_http_server_close( fd_http_server_t * http,
301 : ulong conn_id,
302 : int reason );
303 :
304 : /* Close an active WebSocket conection. The connection ID must be an
305 : open WebSocket connection ID in [0, max_ws_connection_cnt). The
306 : connection will be forcibly (ungracefully) terminated. The
307 : connection ID is released and should not be used again, as it may be
308 : recycled for a future WebSocket connection. If a ws_close callback
309 : has been provided to the http server, it will be invoked with the
310 : reason provided. */
311 :
312 : void
313 : fd_http_server_ws_close( fd_http_server_t * http,
314 : ulong ws_conn_id,
315 : int reason );
316 :
317 : /* fd_http_server_buffer_trunc truncates the pending message to the given length. */
318 :
319 : void
320 : fd_http_server_stage_trunc( fd_http_server_t * http,
321 : ulong len );
322 :
323 : /* fd_http_server_buffer_len returns the length of the pending message. */
324 :
325 : ulong
326 : fd_http_server_stage_len( fd_http_server_t * http );
327 :
328 : /* fd_http_server_printf appends the rendered format string fmt into the
329 : staging area of the outgoing ring buffer. Assumes http is a current
330 : local join.
331 :
332 : If appending to the ring buffer causes it to wrap around and
333 : overwrite existing data from a prior message, any connections which
334 : are still using data from the prior message will be evicted, as they
335 : cannot keep up.
336 :
337 : Once the full message has been appended into the outgoing ring buffer,
338 : the staged contents can be sent to all connected WebSocket clients of
339 : the HTTP server using fd_http_server_broadcast. This will end the
340 : current staged message so future prints go into a new message.
341 :
342 : Printing is not error-free, it is assumed that the format string is
343 : valid but the entire outgoing buffer may not be large enough to hold
344 : the printed string. In that case, the staging buffer is marked as
345 : being in an error state internally. The next call to send or
346 : broadcast will fail, returning the error, and the error state will be
347 : cleared. */
348 :
349 : void
350 : fd_http_server_printf( fd_http_server_t * http,
351 : char const * fmt,
352 : ... ) __attribute__((format (printf, 2, 3)));
353 :
354 : /* fd_http_server_memcpy appends the data provided to the end of the
355 : staging area of the outgoing ring buffer. Assumes http is a current
356 : local join.
357 :
358 : If appending to the ring buffer causes it to wrap around and
359 : overwrite existing data from a prior message, any connections which
360 : are still using data from the prior message will be evicted, as they
361 : cannot keep up.
362 :
363 : Once the full message has been appended into the outgoing ring buffer,
364 : the staged contents can be sent to all connected WebSocket clients of
365 : the HTTP server using fd_http_server_broadcast. This will end the
366 : current staged message so future prints go into a new message.
367 :
368 : Printing is not error-free, it is assumed that the format string is
369 : valid but the entire outgoing buffer may not be large enough to hold
370 : the printed string. In that case, the staging buffer is marked as
371 : being in an error state internally. The next call to send or
372 : broadcast will fail, returning the error, and the error state will be
373 : cleared. */
374 :
375 : void
376 : fd_http_server_memcpy( fd_http_server_t * http,
377 : uchar const * data,
378 : ulong data_len );
379 :
380 : /* fd_http_server_unstage unstages any data written into the staging
381 : buffer, clearing its contents. It does not advance the ring buffer
382 : usage, and no clients will be evicted. */
383 :
384 : void
385 : fd_http_server_unstage( fd_http_server_t * http );
386 :
387 : /* fd_http_server_stage_body marks the current contents of the staging
388 : buffer as the body of the response. The response is then ready to be
389 : sent to the client. Returns 0 on success and -1 on failure if the
390 : ring buffer is in an error state, and then clears the error state. */
391 :
392 : int
393 : fd_http_server_stage_body( fd_http_server_t * http,
394 : fd_http_server_response_t * response );
395 :
396 : /* Send the contents of the staging buffer as a a WebSocket message to a
397 : single client. The staging buffer is then cleared. Returns -1 on
398 : failure if the ring buffer is an error state, and then clears the
399 : error state.
400 :
401 : The contents are marked as needing to be sent to the client, but this
402 : does not block or wait for them to send, which happens async as the
403 : client is able to read. If the client reads too slow, and the
404 : staging buffer wraps around and is eventually overwritten by another
405 : printer, this client will be force disconnected as being too slow. */
406 :
407 : int
408 : fd_http_server_ws_send( fd_http_server_t * http,
409 : ulong ws_conn_id ); /* An existing, open connection. In [0, max_ws_connection_cnt) */
410 :
411 : /* Broadcast the contents of the staging buffer as a WebSocket message
412 : to all connected clients. The staging buffer is then cleared.
413 : Returns -1 on failure if the ring buffer is an error state, and then
414 : clears the error state.
415 :
416 : The contents are marked as needing to be sent to the client, but this
417 : does not block or wait for them to send, which happens async as the
418 : client is able to read. If the client reads too slow, and the
419 : staging buffer wraps around and is eventually overwritten by another
420 : printer, this client will be force disconnected as being too slow. */
421 :
422 : int
423 : fd_http_server_ws_broadcast( fd_http_server_t * http );
424 :
425 : /* fd_http_server_poll needs to be continuously called in a spin loop to
426 : drive the HTTP server forward. poll_timeout is the timeout arg to
427 : poll(2). poll_timeout==0 does a non-blocking socket poll. Returns
428 : 1 if there was any work to do on the HTTP server, or 0 otherwise. */
429 :
430 : int
431 : fd_http_server_poll( fd_http_server_t * http,
432 : int poll_timeout );
433 :
434 : FD_PROTOTYPES_END
435 :
436 : #endif /* HEADER_fd_src_ballet_http_fd_http_server_h */
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