1 Testing server with a browser
2 -----------------------------
4 If you run libwebsockets-test-server and point your browser
9 It will fetch a script in the form of test.html, and then run the
10 script in there on the browser to open a websocket connection.
11 Incrementing numbers should appear in the browser display.
13 By default the test server logs to both stderr and syslog, you can control
14 what is logged using -d <log level>, see later.
17 Running test server as a Daemon
18 -------------------------------
20 You can use the -D option on the test server to have it fork into the
21 background and return immediately. In this daemonized mode all stderr is
22 disabled and logging goes only to syslog, eg, /var/log/messages or similar.
24 The server maintains a lockfile at /tmp/.lwsts-lock that contains the pid
25 of the master process, and deletes this file when the master process
28 To stop the daemon, do
30 kill `cat /tmp/.lwsts-lock`
32 If it finds a stale lock (the pid mentioned in the file does not exist
33 any more) it will delete the lock and create a new one during startup.
35 If the lock is valid, the daemon will exit with a note on stderr that
36 it was already running.s
39 Using SSL on the server side
40 ----------------------------
42 To test it using SSL/WSS, just run the test server with
44 $ libwebsockets-test-server --ssl
48 https://127.0.0.1:7681
50 The connection will be entirely encrypted using some generated
51 certificates that your browser will not accept, since they are
52 not signed by any real Certificate Authority. Just accept the
53 certificates in the browser and the connection will proceed
54 in first https and then websocket wss, acting exactly the
57 test-server.c is all that is needed to use libwebsockets for
58 serving both the script html over http and websockets.
61 Testing websocket client support
62 --------------------------------
64 If you run the test server as described above, you can also
65 connect to it using the test client as well as a browser.
67 $ libwebsockets-test-client localhost
69 will by default connect to the test server on localhost:7681
70 and print the dumb increment number from the server at the
71 same time as drawing random circles in the mirror protocol;
72 if you connect to the test server using a browser at the
73 same time you will be able to see the circles being drawn.
79 You can test against echo.websockets.org as a sanity test like
80 this (the client connects to port 80 by default):
82 $ libwebsockets-test-echo --client echo.websocket.org
84 This echo test is of limited use though because it doesn't
85 negotiate any protocol. You can run the same test app as a
86 local server, by default on localhost:7681
88 $ libwebsockets-test-echo
90 and do the echo test against the local echo server
92 $ libwebsockets-test-echo --client localhost --port 7681
94 If you add the --ssl switch to both the client and server, you can also test
95 with an encrypted link.
98 Testing SSL on the client side
99 ------------------------------
101 To test SSL/WSS client action, just run the client test with
103 $ libwebsockets-test-client localhost --ssl
105 By default the client test applet is set to accept selfsigned
106 certificates used by the test server, this is indicated by the
107 use_ssl var being set to 2. Set it to 1 to reject any server
108 certificate that it doesn't have a trusted CA cert for.
111 Using the websocket ping utility
112 --------------------------------
114 libwebsockets-test-ping connects as a client to a remote
115 websocket server using 04 protocol and pings it like the
116 normal unix ping utility.
118 $ libwebsockets-test-ping localhost
119 handshake OK for protocol lws-mirror-protocol
120 Websocket PING localhost.localdomain (127.0.0.1) 64 bytes of data.
121 64 bytes from localhost: req=1 time=0.1ms
122 64 bytes from localhost: req=2 time=0.1ms
123 64 bytes from localhost: req=3 time=0.1ms
124 64 bytes from localhost: req=4 time=0.2ms
125 64 bytes from localhost: req=5 time=0.1ms
126 64 bytes from localhost: req=6 time=0.2ms
127 64 bytes from localhost: req=7 time=0.2ms
128 64 bytes from localhost: req=8 time=0.1ms
130 --- localhost.localdomain websocket ping statistics ---
131 8 packets transmitted, 8 received, 0% packet loss, time 7458ms
132 rtt min/avg/max = 0.110/0.185/0.218 ms
135 By default it sends 64 byte payload packets using the 04
136 PING packet opcode type. You can change the payload size
137 using the -s= flag, up to a maximum of 125 mandated by the
140 Using the lws-mirror protocol that is provided by the test
141 server, libwebsockets-test-ping can also use larger payload
142 sizes up to 4096 is BINARY packets; lws-mirror will copy
143 them back to the client and they appear as a PONG. Use the
144 -m flag to select this operation.
146 The default interval between pings is 1s, you can use the -i=
147 flag to set this, including fractions like -i=0.01 for 10ms
150 Before you can even use the PING opcode that is part of the
151 standard, you must complete a handshake with a specified
152 protocol. By default lws-mirror-protocol is used which is
153 supported by the test server. But if you are using it on
154 another server, you can specify the protcol to handshake with
155 by --protocol=protocolname
161 By default it runs in server mode
163 $ libwebsockets-test-fraggle
164 libwebsockets test fraggle
165 (C) Copyright 2010-2011 Andy Green <andy@warmcat.com> licensed under LGPL2.1
166 Compiled with SSL support, not using it
167 Listening on port 7681
168 server sees client connect
169 accepted v06 connection
170 Spamming 360 random fragments
171 Spamming session over, len = 371913. sum = 0x2D3C0AE
172 Spamming 895 random fragments
173 Spamming session over, len = 875970. sum = 0x6A74DA1
176 You need to run a second session in client mode, you have to
177 give the -c switch and the server address at least:
179 $ libwebsockets-test-fraggle -c localhost
180 libwebsockets test fraggle
181 (C) Copyright 2010-2011 Andy Green <andy@warmcat.com> licensed under LGPL2.1
183 Connecting to localhost:7681
184 denied deflate-stream extension
185 handshake OK for protocol fraggle-protocol
186 client connects to server
187 EOM received 371913 correctly from 360 fragments
188 EOM received 875970 correctly from 895 fragments
189 EOM received 247140 correctly from 258 fragments
190 EOM received 695451 correctly from 692 fragments
193 The fraggle test sends a random number up to 1024 fragmented websocket frames
194 each of a random size between 1 and 2001 bytes in a single message, then sends
195 a checksum and starts sending a new randomly sized and fragmented message.
197 The fraggle test client receives the same message fragments and computes the
198 same checksum using websocket framing to see when the message has ended. It
199 then accepts the server checksum message and compares that to its checksum.
205 The http_proxy environment variable is respected by the client
206 connection code for both ws:// and wss://. It doesn't support
211 export http_proxy=myproxy.com:3128
212 libwebsockets-test-client someserver.com
218 By default logging of severity "notice", "warn" or "err" is enabled to stderr.
220 Again by default other logging is comiled in but disabled from printing.
222 If you want to eliminate the debug logging below notice in severity, use the
223 --disable-debug configure option to have it removed from the code by the
226 If you want to see more detailed debug logs, you can control a bitfield to
227 select which logs types may print using the lws_set_log_level() api, in the
228 test apps you can use -d <number> to control this. The types of logging
229 available are (OR together the numbers to select multiple)
243 Websocket version supported
244 ---------------------------
246 The final IETF standard is supported for both client and server, protocol
253 Since libwebsockets runs using poll() and a single threaded approach, any
254 unexpected latency coming from system calls would be bad news. There's now
255 a latency tracking scheme that can be built in with --with-latency at
256 configure-time, logging the time taken for system calls to complete and if
257 the whole action did complete that time or was deferred.
259 You can see the detailed data by enabling logging level 512 (eg, -d 519 on
260 the test server to see that and the usual logs), however even without that
261 the "worst" latency is kept and reported to the logs with NOTICE severity
262 when the context is destroyed.
264 Some care is needed interpreting them, if the action completed the first figure
265 (in us) is the time taken for the whole action, which may have retried through
266 the poll loop many times and will depend on network roundtrip times. High
267 figures here don't indicate a problem. The figure in us reported after "lat"
268 in the logging is the time taken by this particular attempt. High figures
269 here may indicate a problem, or if you system is loaded with another app at
270 that time, such as the browser, it may simply indicate the OS gave preferential
271 treatment to the other app during that call.