| 12 |
|
- Client Control Protocol |
| 13 |
|
- Client Data Protocol |
| 14 |
|
|
| 15 |
– |
|
| 15 |
|
Conventions |
| 16 |
|
----------- |
| 17 |
|
All protocols in this document assume a valid connection of |
| 25 |
|
character. For example: |
| 26 |
|
|
| 27 |
|
[OK|ERROR] |
| 28 |
< |
|
| 28 |
> |
|
| 29 |
|
Indicates that the message "OK" OR the message "ERROR" will |
| 30 |
|
be sent depending on the result of the last action. |
| 31 |
|
|
| 35 |
|
|
| 36 |
|
{lastmodified} |
| 37 |
|
|
| 38 |
< |
Indicates that data for use as 'last modified' will be |
| 39 |
< |
returned. |
| 38 |
> |
Indicates that data for use as 'last modified' will be |
| 39 |
> |
returned. |
| 40 |
|
|
| 41 |
< |
If [ERROR] is sent back at any time, this indicates that all |
| 41 |
> |
If [ERROR] is sent back at any time, this indicates that all |
| 42 |
|
communication is over. EXCEPT where otherwise specified! |
| 43 |
|
|
| 45 |
– |
|
| 44 |
|
Host Connection Protocol |
| 45 |
|
------------------------ |
| 46 |
|
The initial connection of a host to the i-scream server is |
| 56 |
|
[STARTCONFIG]----------> Requests to start |
| 57 |
|
receiving config |
| 58 |
|
information |
| 59 |
< |
|
| 59 |
> |
|
| 60 |
|
<---------- [OK|ERROR] If the server ok's |
| 61 |
|
the request or not |
| 62 |
|
|
| 65 |
|
(used when checking |
| 66 |
|
if the config has |
| 67 |
|
changed) |
| 68 |
< |
|
| 68 |
> |
|
| 69 |
|
<---------- [{lastmodified}Returns a long int |
| 70 |
|
|ERROR] time since epoch |
| 71 |
|
eg, 123456789 |
| 76 |
|
"measured in milli |
| 77 |
|
-seconds since the |
| 78 |
|
epoch" |
| 79 |
< |
|
| 79 |
> |
|
| 80 |
|
[FILELIST] ----------> Asks the server for |
| 81 |
|
the list of files |
| 82 |
|
that were used to |
| 84 |
|
(used when checking |
| 85 |
|
if the config has |
| 86 |
|
changed) |
| 87 |
< |
|
| 87 |
> |
|
| 88 |
|
<---------- [{filelist} Returns a semi-colon |
| 89 |
|
|ERROR] separated list of |
| 90 |
|
filenames |
| 100 |
|
retrieved from the |
| 101 |
|
config file |
| 102 |
|
eg, UDPUpdateTime |
| 103 |
< |
|
| 103 |
> |
|
| 104 |
|
<---------- [{value}|ERROR]Returns the value of |
| 105 |
|
the requested config |
| 106 |
|
property |
| 109 |
|
find the requested |
| 110 |
|
property it returns |
| 111 |
|
ERROR to indicate |
| 112 |
< |
that fact, but |
| 113 |
< |
communication still |
| 112 |
> |
that fact, but |
| 113 |
> |
communication still |
| 114 |
|
proceeds |
| 115 |
< |
|
| 115 |
> |
|
| 116 |
|
********** LOOP UNTIL ********** |
| 117 |
|
The loop continues until the host |
| 118 |
|
sends the following message |
| 119 |
< |
|
| 119 |
> |
|
| 120 |
|
[ENDCONFIG] ----------> Indicates that the |
| 121 |
|
host requires no |
| 122 |
|
more config |
| 123 |
< |
|
| 123 |
> |
|
| 124 |
|
********** LOOP END ********** |
| 125 |
|
Communication continues |
| 126 |
< |
|
| 126 |
> |
|
| 127 |
|
<---------- [OK] Indicates that the |
| 128 |
|
server is ready to |
| 129 |
|
proceed |
| 130 |
< |
|
| 130 |
> |
|
| 131 |
|
[FILTER] ----------> Asks the server to |
| 132 |
|
send it the host |
| 133 |
|
information of a |
| 134 |
|
filter that it |
| 135 |
|
should connect to |
| 136 |
< |
|
| 136 |
> |
|
| 137 |
|
<---------- {filter} Returns a semi-colon |
| 138 |
|
separated list of |
| 139 |
|
FQDN hostname, UDP |
| 151 |
|
server that the host |
| 152 |
|
has finished an will |
| 153 |
|
disconnect |
| 154 |
< |
|
| 154 |
> |
|
| 155 |
|
<---------- [OK|ERROR] Indicates that the |
| 156 |
|
server is either ok |
| 157 |
|
or that it thought |
| 158 |
|
there was an error |
| 159 |
|
------------------------------------------------------------ |
| 160 |
< |
|
| 160 |
> |
|
| 161 |
|
Host Heartbeat Protocol |
| 162 |
|
----------------------- |
| 163 |
|
When a host is configured after it has connected it should |
| 175 |
|
[HEARTBEAT] ----------> Starts the |
| 176 |
|
heartbeat protocol |
| 177 |
|
off |
| 178 |
< |
|
| 178 |
> |
|
| 179 |
|
<---------- [OK|ERROR] Indicates that the |
| 180 |
|
server is ok or not |
| 181 |
|
|
| 238 |
|
server that the host |
| 239 |
|
has finished an will |
| 240 |
|
disconnect |
| 241 |
< |
|
| 241 |
> |
|
| 242 |
|
<---------- [OK|ERROR] Indicates that the |
| 243 |
|
server is either ok |
| 244 |
|
or that it thought |
| 259 |
|
The client control protocol channel is opened by the client |
| 260 |
|
and allows a variety of actions to be carried out by the |
| 261 |
|
client at anytime. Unlike previous protocols, this is NOT |
| 262 |
< |
sequential, all of the requests can be carried out in |
| 262 |
> |
sequential, all of the requests can be carried out in |
| 263 |
|
any order. |
| 264 |
|
|
| 265 |
|
All client protocols are backwards compatible, and the |
| 285 |
|
Host (direction) Server Comment |
| 286 |
|
------------------------------------------------------------ |
| 287 |
|
<initialise> |
| 288 |
< |
[CONNECT] ----------> Starts off the |
| 288 |
> |
[CONNECT] ----------> Starts off the |
| 289 |
|
client protocol |
| 290 |
< |
|
| 290 |
> |
|
| 291 |
|
<---------- [{protocol}] The server sends the |
| 292 |
|
protocol identifier |
| 293 |
< |
|
| 293 |
> |
|
| 294 |
|
[{name}] ----------> The client sends its |
| 295 |
|
"name". This name |
| 296 |
|
is used to identify |
| 298 |
|
to the system and |
| 299 |
|
obtain its config |
| 300 |
|
eg, Conient |
| 301 |
< |
|
| 301 |
> |
|
| 302 |
|
<---------- [OK] Indicates the server |
| 303 |
|
is ok to proceed |
| 304 |
< |
|
| 304 |
> |
|
| 305 |
|
|
| 306 |
|
<command #1> (allows client to obtain its configuration) |
| 307 |
|
[STARTCONFIG]----------> Tell the server we |
| 308 |
|
want to start this |
| 309 |
|
command |
| 310 |
< |
|
| 310 |
> |
|
| 311 |
|
<---------- [OK] Indicates the server |
| 312 |
|
is ok to proceed |
| 313 |
< |
|
| 313 |
> |
|
| 314 |
|
********** LOOP START ********** |
| 315 |
|
This loop reads configuration |
| 316 |
|
properties from the config |
| 321 |
|
config file |
| 322 |
|
Clients can obtain |
| 323 |
|
host information |
| 324 |
< |
eg, |
| 324 |
> |
eg, |
| 325 |
|
Host.UDPUpdateTime |
| 326 |
|
Otherwise it must |
| 327 |
|
prefix requests |
| 329 |
|
All other requests |
| 330 |
|
will be ignored as |
| 331 |
|
if it was unable to |
| 332 |
< |
retieve the property |
| 333 |
< |
|
| 332 |
> |
retrieve the |
| 333 |
> |
property |
| 334 |
> |
|
| 335 |
|
<---------- [{value}|ERROR]Returns the value of |
| 336 |
|
the requested config |
| 337 |
|
property |
| 338 |
|
eg, 120 |
| 339 |
|
If it is unable to |
| 340 |
< |
find the requested |
| 340 |
> |
find the requested |
| 341 |
|
property it returns |
| 342 |
|
ERROR to indicate |
| 343 |
|
that fact |
| 344 |
< |
|
| 344 |
> |
|
| 345 |
|
********** LOOP UNTIL ********** |
| 346 |
|
The loop continues until the client |
| 347 |
|
sends the following message |
| 348 |
< |
|
| 349 |
< |
[ENDCONFIG] ----------> Indicates that the |
| 348 |
> |
|
| 349 |
> |
[ENDCONFIG] ----------> Indicates that the |
| 350 |
|
client requires no |
| 351 |
|
more config |
| 352 |
< |
|
| 352 |
> |
|
| 353 |
|
********** LOOP END ********** |
| 354 |
|
Communication continues |
| 355 |
< |
|
| 355 |
> |
|
| 356 |
|
<---------- [OK] Indicates that the |
| 357 |
|
server is ready to |
| 358 |
|
proceed |
| 361 |
|
[STARTDATA] ----------> Tell the server we |
| 362 |
|
want to start this |
| 363 |
|
command |
| 364 |
< |
|
| 364 |
> |
|
| 365 |
|
<---------- [{portnumber} The server then sets |
| 366 |
|
|ERROR] itself listening for |
| 367 |
|
a connection on its |
| 371 |
|
that it is listening |
| 372 |
|
on eg, 12367 |
| 373 |
|
If the data link is |
| 374 |
< |
yet to be started |
| 375 |
< |
the server will |
| 376 |
< |
return ERROR |
| 377 |
< |
|
| 378 |
< |
<---------- [OK] Indicates the server |
| 379 |
< |
is ok to proceed and |
| 380 |
< |
the client can |
| 381 |
< |
then connect its |
| 383 |
< |
data link |
| 374 |
> |
already started the |
| 375 |
> |
server will return |
| 376 |
> |
ERROR |
| 377 |
> |
|
| 378 |
> |
<---------- [OK] Indicates the client |
| 379 |
> |
has successfully |
| 380 |
> |
connected to the |
| 381 |
> |
data socket. |
| 382 |
|
|
| 383 |
|
<command #3> (tells the server to stop the data link) |
| 384 |
|
[STOPDATA] ----------> Tell the server we |
| 385 |
|
want to start this |
| 386 |
|
command |
| 387 |
|
The server then |
| 388 |
< |
shuts down the |
| 388 |
> |
shuts down the |
| 389 |
|
data link to the |
| 390 |
|
client |
| 391 |
|
|
| 401 |
|
client wants to |
| 402 |
|
close the control |
| 403 |
|
link |
| 404 |
< |
|
| 404 |
> |
|
| 405 |
|
<---------- [OK] The last word from |
| 406 |
|
the server, it will |
| 407 |
< |
disappear after this |
| 407 |
> |
disappear after |
| 408 |
> |
this, and close the |
| 409 |
> |
data link if |
| 410 |
> |
required |
| 411 |
|
------------------------------------------------------------ |
| 412 |
|
|
| 413 |
|
v1.1 - Protocol identifier: "PROTOCOL 1.1" (without quotes) |
| 421 |
|
[SETHOSTLIST]----------> Tell the server we |
| 422 |
|
want to start this |
| 423 |
|
command |
| 424 |
< |
|
| 424 |
> |
|
| 425 |
|
<---------- [OK|ERROR] The server will |
| 426 |
|
return an ERROR if |
| 427 |
|
the data link is |
| 428 |
|
open, as a host list |
| 429 |
< |
must ONLY be set |
| 429 |
> |
must ONLY be set |
| 430 |
|
if the data link is |
| 431 |
|
closed |
| 432 |
|
If the server is |
| 441 |
|
recieve data from |
| 442 |
|
eg, |
| 443 |
|
raptor.ukc.ac.uk;killigrew.ukc.ac.uk;chalk.ukc.ac.uk |
| 444 |
< |
|
| 444 |
> |
|
| 445 |
|
If the list is sent |
| 446 |
|
blank (or if no list |
| 447 |
|
is set at all) then |
| 448 |
|
data from ALL hosts |
| 449 |
|
will be sent to the |
| 450 |
< |
client |
| 451 |
< |
|
| 450 |
> |
client (this is the |
| 451 |
> |
default if no |
| 452 |
> |
SETHOSTLIST is not |
| 453 |
> |
run by the client |
| 454 |
> |
|
| 455 |
|
<---------- [OK] Indicates the server |
| 456 |
|
is ok to proceed and |
| 457 |
< |
the host list has |
| 457 |
> |
the host list has |
| 458 |
|
been accepted |
| 459 |
|
------------------------------------------------------------ |
| 460 |
|
|
| 461 |
|
Client Data Protocol |
| 462 |
|
-------------------- |
| 463 |
|
Once the data link has been opened by the control link, the |
| 464 |
< |
server will send XML formated data packets seperated by the |
| 465 |
< |
\n (newline) character. For information on the format of |
| 464 |
> |
server will send XML formatted data packets separated by the |
| 465 |
> |
\n (newline) character. For information on the format of |
| 466 |
|
this data see the XML via UDP specification document at: |
| 467 |
|
|
| 468 |
|
http://www.i-scream.org.uk/cgi-bin/docs.cgi?doc=specification/xml_via_udp.txt |
