ais.ais_msg

1 #!/usr/bin/env python 2 3 __version__ = '$Revision: 4791 $'.split()[1] 4 __date__ = '$Date: 2007-12-04 $'.split()[1] 5 __author__ = 'xmlbinmsg' 6 7 __doc__=''' 8 9 Autogenerated python functions to serialize/deserialize binary messages. 10 11 Generated by: ./aisxmlbinmsg2py.py 12 13 Need to then wrap these functions with the outer AIS packet and then 14 convert the whole binary blob to a NMEA string. Those functions are 15 not currently provided in this file. 16 17 serialize: python to ais binary 18 deserialize: ais binary to python 19 20 The generated code uses translators.py, binary.py, and aisstring.py 21 which should be packaged with the resulting files. 22 23 24 @requires: U{epydoc<http://epydoc.sourceforge.net/>} > 3.0alpha3 25 @requires: U{BitVector<http://cheeseshop.python.org/pypi/BitVector>} 26 27 @author: '''+__author__+''' 28 @version: ''' + __version__ +''' 29 @var __date__: Date of last svn commit 30 @undocumented: __version__ __author__ __doc__ parser 31 @status: under development 32 @license: Generated code has no license 33 @todo: FIX: put in a description of the message here with fields and types. 34 ''' 35 36 import sys 37 from decimal import Decimal 38 from BitVector import BitVector 39 40 import binary, aisstring 41 42 # FIX: check to see if these will be needed 43 TrueBV = BitVector(bitstring="1") 44 "Why always rebuild the True bit? This should speed things up a bunch" 45 FalseBV = BitVector(bitstring="0") 46 "Why always rebuild the False bit? This should speed things up a bunch" 47 48 49 fieldList = ( 50 'MessageID', 51 'RepeatIndicator', 52 'UserID', 53 'Spare', 54 'DestID1', 55 'SeqID1', 56 'DestID2', 57 'SeqID2', 58 'DestID3', 59 'SeqID3', 60 'DestID4', 61 'SeqID4', 62 ) 63 64 fieldListPostgres = ( 65 'MessageID', 66 'RepeatIndicator', 67 'UserID', 68 'Spare', 69 'DestID1', 70 'SeqID1', 71 'DestID2', 72 'SeqID2', 73 'DestID3', 74 'SeqID3', 75 'DestID4', 76 'SeqID4', 77 ) 78 79 toPgFields = { 80 } 81 ''' 82 Go to the Postgis field names from the straight field name 83 ''' 84 85 fromPgFields = { 86 } 87 ''' 88 Go from the Postgis field names to the straight field name 89 ''' 90 91 pgTypes = { 92 } 93 ''' 94 Lookup table for each postgis field name to get its type. 95 ''' 96

97 -def encode(params, validate=False):

98 '''Create a binack binary message payload to pack into an AIS Msg binack. 99 100 Fields in params: 101 - MessageID(uint): AIS message number. Must be 7 (field automatically set to "7") 102 - RepeatIndicator(uint): Indicated how many times a message has been repeated 103 - UserID(uint): Unique ship identification number (MMSI). Also known as the Source ID 104 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 105 - DestID1(uint): MMSI destication to ACK 106 - SeqID1(uint): Sequence ID of the message to be acknowledged 107 - DestID2(uint): MMSI destication to ACK 108 - SeqID2(uint): Sequence ID of the message to be acknowledged 109 - DestID3(uint): MMSI destication to ACK 110 - SeqID3(uint): Sequence ID of the message to be acknowledged 111 - DestID4(uint): MMSI destication to ACK 112 - SeqID4(uint): Sequence ID of the message to be acknowledged 113 @param params: Dictionary of field names/values. Throws a ValueError exception if required is missing 114 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 115 @rtype: BitVector 116 @return: encoded binary message (for binary messages, this needs to be wrapped in a msg 8 117 @note: The returned bits may not be 6 bit aligned. It is up to you to pad out the bits. 118 ''' 119 120 bvList = [] 121 bvList.append(binary.setBitVectorSize(BitVector(intVal=7),6)) 122 if 'RepeatIndicator' in params: 123 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['RepeatIndicator']),2)) 124 else: 125 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),2)) 126 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['UserID']),30)) 127 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),1)) 128 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['DestID1']),30)) 129 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['SeqID1']),2)) 130 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['DestID2']),30)) 131 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['SeqID2']),2)) 132 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['DestID3']),30)) 133 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['SeqID3']),2)) 134 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['DestID4']),30)) 135 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['SeqID4']),2)) 136 137 return binary.joinBV(bvList)

138

139 -def decode(bv, validate=False):

140 '''Unpack a binack message 141 142 Fields in params: 143 - MessageID(uint): AIS message number. Must be 7 (field automatically set to "7") 144 - RepeatIndicator(uint): Indicated how many times a message has been repeated 145 - UserID(uint): Unique ship identification number (MMSI). Also known as the Source ID 146 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 147 - DestID1(uint): MMSI destication to ACK 148 - SeqID1(uint): Sequence ID of the message to be acknowledged 149 - DestID2(uint): MMSI destication to ACK 150 - SeqID2(uint): Sequence ID of the message to be acknowledged 151 - DestID3(uint): MMSI destication to ACK 152 - SeqID3(uint): Sequence ID of the message to be acknowledged 153 - DestID4(uint): MMSI destication to ACK 154 - SeqID4(uint): Sequence ID of the message to be acknowledged 155 @type bv: BitVector 156 @param bv: Bits defining a message 157 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 158 @rtype: dict 159 @return: params 160 ''' 161 162 #Would be nice to check the bit count here.. 163 #if validate: 164 # assert (len(bv)==FIX: SOME NUMBER) 165 r = {} 166 r['MessageID']=7 167 r['RepeatIndicator']=int(bv[6:8]) 168 r['UserID']=int(bv[8:38]) 169 r['Spare']=0 170 r['DestID1']=int(bv[39:69]) 171 r['SeqID1']=int(bv[69:71]) 172 r['DestID2']=int(bv[71:101]) 173 r['SeqID2']=int(bv[101:103]) 174 r['DestID3']=int(bv[103:133]) 175 r['SeqID3']=int(bv[133:135]) 176 r['DestID4']=int(bv[135:165]) 177 r['SeqID4']=int(bv[165:167]) 178 return r

179

180 -def decodeMessageID(bv, validate=False):

181 return 7

182

183 -def decodeRepeatIndicator(bv, validate=False):

184 return int(bv[6:8])

185

186 -def decodeUserID(bv, validate=False):

187 return int(bv[8:38])

188

189 -def decodeSpare(bv, validate=False):

190 return 0

191

192 -def decodeDestID1(bv, validate=False):

193 return int(bv[39:69])

194

195 -def decodeSeqID1(bv, validate=False):

196 return int(bv[69:71])

197

198 -def decodeDestID2(bv, validate=False):

199 return int(bv[71:101])

200

201 -def decodeSeqID2(bv, validate=False):

202 return int(bv[101:103])

203

204 -def decodeDestID3(bv, validate=False):

205 return int(bv[103:133])

206

207 -def decodeSeqID3(bv, validate=False):

208 return int(bv[133:135])

209

210 -def decodeDestID4(bv, validate=False):

211 return int(bv[135:165])

212

213 -def decodeSeqID4(bv, validate=False):

214 return int(bv[165:167])

215 216

217 -def printHtml(params, out=sys.stdout):

218 out.write("<h3>binack</h3>\n") 219 out.write("<table border=\"1\">\n") 220 out.write("<tr bgcolor=\"orange\">\n") 221 out.write("<th align=\"left\">Field Name</th>\n") 222 out.write("<th align=\"left\">Type</th>\n") 223 out.write("<th align=\"left\">Value</th>\n") 224 out.write("<th align=\"left\">Value in Lookup Table</th>\n") 225 out.write("<th align=\"left\">Units</th>\n") 226 out.write("\n") 227 out.write("<tr>\n") 228 out.write("<td>MessageID</td>\n") 229 out.write("<td>uint</td>\n") 230 if 'MessageID' in params: 231 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 232 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 233 out.write("</tr>\n") 234 out.write("\n") 235 out.write("<tr>\n") 236 out.write("<td>RepeatIndicator</td>\n") 237 out.write("<td>uint</td>\n") 238 if 'RepeatIndicator' in params: 239 out.write(" <td>"+str(params['RepeatIndicator'])+"</td>\n") 240 if str(params['RepeatIndicator']) in RepeatIndicatorDecodeLut: 241 out.write("<td>"+RepeatIndicatorDecodeLut[str(params['RepeatIndicator'])]+"</td>") 242 else: 243 out.write("<td><i>Missing LUT entry</i></td>") 244 out.write("</tr>\n") 245 out.write("\n") 246 out.write("<tr>\n") 247 out.write("<td>UserID</td>\n") 248 out.write("<td>uint</td>\n") 249 if 'UserID' in params: 250 out.write(" <td>"+str(params['UserID'])+"</td>\n") 251 out.write(" <td>"+str(params['UserID'])+"</td>\n") 252 out.write("</tr>\n") 253 out.write("\n") 254 out.write("<tr>\n") 255 out.write("<td>Spare</td>\n") 256 out.write("<td>uint</td>\n") 257 if 'Spare' in params: 258 out.write(" <td>"+str(params['Spare'])+"</td>\n") 259 out.write(" <td>"+str(params['Spare'])+"</td>\n") 260 out.write("</tr>\n") 261 out.write("\n") 262 out.write("<tr>\n") 263 out.write("<td>DestID1</td>\n") 264 out.write("<td>uint</td>\n") 265 if 'DestID1' in params: 266 out.write(" <td>"+str(params['DestID1'])+"</td>\n") 267 out.write(" <td>"+str(params['DestID1'])+"</td>\n") 268 out.write("</tr>\n") 269 out.write("\n") 270 out.write("<tr>\n") 271 out.write("<td>SeqID1</td>\n") 272 out.write("<td>uint</td>\n") 273 if 'SeqID1' in params: 274 out.write(" <td>"+str(params['SeqID1'])+"</td>\n") 275 out.write(" <td>"+str(params['SeqID1'])+"</td>\n") 276 out.write("</tr>\n") 277 out.write("\n") 278 out.write("<tr>\n") 279 out.write("<td>DestID2</td>\n") 280 out.write("<td>uint</td>\n") 281 if 'DestID2' in params: 282 out.write(" <td>"+str(params['DestID2'])+"</td>\n") 283 out.write(" <td>"+str(params['DestID2'])+"</td>\n") 284 out.write("</tr>\n") 285 out.write("\n") 286 out.write("<tr>\n") 287 out.write("<td>SeqID2</td>\n") 288 out.write("<td>uint</td>\n") 289 if 'SeqID2' in params: 290 out.write(" <td>"+str(params['SeqID2'])+"</td>\n") 291 out.write(" <td>"+str(params['SeqID2'])+"</td>\n") 292 out.write("</tr>\n") 293 out.write("\n") 294 out.write("<tr>\n") 295 out.write("<td>DestID3</td>\n") 296 out.write("<td>uint</td>\n") 297 if 'DestID3' in params: 298 out.write(" <td>"+str(params['DestID3'])+"</td>\n") 299 out.write(" <td>"+str(params['DestID3'])+"</td>\n") 300 out.write("</tr>\n") 301 out.write("\n") 302 out.write("<tr>\n") 303 out.write("<td>SeqID3</td>\n") 304 out.write("<td>uint</td>\n") 305 if 'SeqID3' in params: 306 out.write(" <td>"+str(params['SeqID3'])+"</td>\n") 307 out.write(" <td>"+str(params['SeqID3'])+"</td>\n") 308 out.write("</tr>\n") 309 out.write("\n") 310 out.write("<tr>\n") 311 out.write("<td>DestID4</td>\n") 312 out.write("<td>uint</td>\n") 313 if 'DestID4' in params: 314 out.write(" <td>"+str(params['DestID4'])+"</td>\n") 315 out.write(" <td>"+str(params['DestID4'])+"</td>\n") 316 out.write("</tr>\n") 317 out.write("\n") 318 out.write("<tr>\n") 319 out.write("<td>SeqID4</td>\n") 320 out.write("<td>uint</td>\n") 321 if 'SeqID4' in params: 322 out.write(" <td>"+str(params['SeqID4'])+"</td>\n") 323 out.write(" <td>"+str(params['SeqID4'])+"</td>\n") 324 out.write("</tr>\n") 325 out.write("</table>\n")

326

327 -def printFields(params, out=sys.stdout, format='std', fieldList=None, dbType='postgres'):

328 '''Print a binack message to stdout. 329 330 Fields in params: 331 - MessageID(uint): AIS message number. Must be 7 (field automatically set to "7") 332 - RepeatIndicator(uint): Indicated how many times a message has been repeated 333 - UserID(uint): Unique ship identification number (MMSI). Also known as the Source ID 334 - Spare(uint): Not used. Should be set to zero. (field automatically set to "0") 335 - DestID1(uint): MMSI destication to ACK 336 - SeqID1(uint): Sequence ID of the message to be acknowledged 337 - DestID2(uint): MMSI destication to ACK 338 - SeqID2(uint): Sequence ID of the message to be acknowledged 339 - DestID3(uint): MMSI destication to ACK 340 - SeqID3(uint): Sequence ID of the message to be acknowledged 341 - DestID4(uint): MMSI destication to ACK 342 - SeqID4(uint): Sequence ID of the message to be acknowledged 343 @param params: Dictionary of field names/values. 344 @param out: File like object to write to 345 @rtype: stdout 346 @return: text to out 347 ''' 348 349 if 'std'==format: 350 out.write("binack:\n") 351 if 'MessageID' in params: out.write(" MessageID: "+str(params['MessageID'])+"\n") 352 if 'RepeatIndicator' in params: out.write(" RepeatIndicator: "+str(params['RepeatIndicator'])+"\n") 353 if 'UserID' in params: out.write(" UserID: "+str(params['UserID'])+"\n") 354 if 'Spare' in params: out.write(" Spare: "+str(params['Spare'])+"\n") 355 if 'DestID1' in params: out.write(" DestID1: "+str(params['DestID1'])+"\n") 356 if 'SeqID1' in params: out.write(" SeqID1: "+str(params['SeqID1'])+"\n") 357 if 'DestID2' in params: out.write(" DestID2: "+str(params['DestID2'])+"\n") 358 if 'SeqID2' in params: out.write(" SeqID2: "+str(params['SeqID2'])+"\n") 359 if 'DestID3' in params: out.write(" DestID3: "+str(params['DestID3'])+"\n") 360 if 'SeqID3' in params: out.write(" SeqID3: "+str(params['SeqID3'])+"\n") 361 if 'DestID4' in params: out.write(" DestID4: "+str(params['DestID4'])+"\n") 362 if 'SeqID4' in params: out.write(" SeqID4: "+str(params['SeqID4'])+"\n") 363 elif 'csv'==format: 364 if None == options.fieldList: 365 options.fieldList = fieldList 366 needComma = False; 367 for field in fieldList: 368 if needComma: out.write(',') 369 needComma = True 370 if field in params: 371 out.write(str(params[field])) 372 # else: leave it empty 373 out.write("\n") 374 elif 'html'==format: 375 printHtml(params,out) 376 elif 'sql'==format: 377 sqlInsertStr(params,out,dbType=dbType) 378 else: 379 print "ERROR: unknown format:",format 380 assert False 381 382 return # Nothing to return

383 384 RepeatIndicatorEncodeLut = { 385 'default':'0', 386 'do not repeat any more':'3', 387 } #RepeatIndicatorEncodeLut 388 389 RepeatIndicatorDecodeLut = { 390 '0':'default', 391 '3':'do not repeat any more', 392 } # RepeatIndicatorEncodeLut 393 394 ###################################################################### 395 # SQL SUPPORT 396 ###################################################################### 397

398 -def sqlCreateStr(outfile=sys.stdout, fields=None, extraFields=None 399 ,addCoastGuardFields=True 400 ,dbType='postgres' 401 ):

402 ''' 403 Return the SQL CREATE command for this message type 404 @param outfile: file like object to print to. 405 @param fields: which fields to put in the create. Defaults to all. 406 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 407 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 408 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 409 @type addCoastGuardFields: bool 410 @return: sql create string 411 @rtype: str 412 413 @see: sqlCreate 414 ''' 415 # FIX: should this sqlCreate be the same as in LaTeX (createFuncName) rather than hard coded? 416 outfile.write(str(sqlCreate(fields,extraFields,addCoastGuardFields,dbType=dbType)))

417

418 -def sqlCreate(fields=None, extraFields=None, addCoastGuardFields=True, dbType='postgres'):

419 ''' 420 Return the sqlhelp object to create the table. 421 422 @param fields: which fields to put in the create. Defaults to all. 423 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 424 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 425 @type addCoastGuardFields: bool 426 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 427 @return: An object that can be used to generate a return 428 @rtype: sqlhelp.create 429 ''' 430 if None == fields: fields = fieldList 431 import sqlhelp 432 c = sqlhelp.create('binack',dbType=dbType) 433 c.addPrimaryKey() 434 if 'MessageID' in fields: c.addInt ('MessageID') 435 if 'RepeatIndicator' in fields: c.addInt ('RepeatIndicator') 436 if 'UserID' in fields: c.addInt ('UserID') 437 if 'Spare' in fields: c.addInt ('Spare') 438 if 'DestID1' in fields: c.addInt ('DestID1') 439 if 'SeqID1' in fields: c.addInt ('SeqID1') 440 if 'DestID2' in fields: c.addInt ('DestID2') 441 if 'SeqID2' in fields: c.addInt ('SeqID2') 442 if 'DestID3' in fields: c.addInt ('DestID3') 443 if 'SeqID3' in fields: c.addInt ('SeqID3') 444 if 'DestID4' in fields: c.addInt ('DestID4') 445 if 'SeqID4' in fields: c.addInt ('SeqID4') 446 447 if addCoastGuardFields: 448 # c.addInt('cg_rssi') # Relative signal strength indicator 449 # c.addInt('cg_d') # dBm receive strength 450 # c.addInt('cg_T') # Receive timestamp from the AIS equipment 451 # c.addInt('cg_S') # Slot received in 452 # c.addVarChar('cg_x',10) # Idonno 453 c.addVarChar('cg_r',15) # Receiver station ID - should usually be an MMSI, but sometimes is a string 454 c.addInt('cg_sec') # UTC seconds since the epoch 455 456 c.addTimestamp('cg_timestamp') # UTC decoded cg_sec - not actually in the data stream 457 458 return c

459

460 -def sqlInsertStr(params, outfile=sys.stdout, extraParams=None, dbType='postgres'):

461 ''' 462 Return the SQL INSERT command for this message type 463 @param params: dictionary of values keyed by field name 464 @param outfile: file like object to print to. 465 @param extraParams: A sequence of tuples containing (name,sql type) for additional fields 466 @return: sql create string 467 @rtype: str 468 469 @see: sqlCreate 470 ''' 471 outfile.write(str(sqlInsert(params,extraParams,dbType=dbType)))

472 473

474 -def sqlInsert(params,extraParams=None,dbType='postgres'):

475 ''' 476 Give the SQL INSERT statement 477 @param params: dict keyed by field name of values 478 @param extraParams: any extra fields that you have created beyond the normal ais message fields 479 @rtype: sqlhelp.insert 480 @return: insert class instance 481 @todo: allow optional type checking of params? 482 @warning: this will take invalid keys happily and do what??? 483 ''' 484 import sqlhelp 485 i = sqlhelp.insert('binack',dbType=dbType) 486 487 if dbType=='postgres': 488 finished = [] 489 for key in params: 490 if key in finished: 491 continue 492 493 if key not in toPgFields and key not in fromPgFields: 494 if type(params[key])==Decimal: i.add(key,float(params[key])) 495 else: i.add(key,params[key]) 496 else: 497 if key in fromPgFields: 498 val = params[key] 499 # Had better be a WKT type like POINT(-88.1 30.321) 500 i.addPostGIS(key,val) 501 finished.append(key) 502 else: 503 # Need to construct the type. 504 pgName = toPgFields[key] 505 #valStr='GeomFromText(\''+pgTypes[pgName]+'(' 506 valStr=pgTypes[pgName]+'(' 507 vals = [] 508 for nonPgKey in fromPgFields[pgName]: 509 vals.append(str(params[nonPgKey])) 510 finished.append(nonPgKey) 511 valStr+=' '.join(vals)+')' 512 i.addPostGIS(pgName,valStr) 513 else: 514 for key in params: 515 if type(params[key])==Decimal: i.add(key,float(params[key])) 516 else: i.add(key,params[key]) 517 518 if None != extraParams: 519 for key in extraParams: 520 i.add(key,extraParams[key]) 521 522 return i

523 524 ###################################################################### 525 # LATEX SUPPORT 526 ###################################################################### 527

528 -def latexDefinitionTable(outfile=sys.stdout 529 ):

530 ''' 531 Return the LaTeX definition table for this message type 532 @param outfile: file like object to print to. 533 @type outfile: file obj 534 @return: LaTeX table string via the outfile 535 @rtype: str 536 537 ''' 538 o = outfile 539 540 o.write(''' 541 \\begin{table}%[htb] 542 \\centering 543 \\begin{tabular}{|l|c|l|} 544 \\hline 545 Parameter & Number of bits & Description 546 \\\\ \\hline\\hline 547 MessageID & 6 & AIS message number. Must be 7 \\\\ \hline 548 RepeatIndicator & 2 & Indicated how many times a message has been repeated \\\\ \hline 549 UserID & 30 & Unique ship identification number (MMSI). Also known as the Source ID \\\\ \hline 550 Spare & 1 & Not used. Should be set to zero. \\\\ \hline 551 DestID1 & 30 & MMSI destication to ACK \\\\ \hline 552 SeqID1 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 553 DestID2 & 30 & MMSI destication to ACK \\\\ \hline 554 SeqID2 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 555 DestID3 & 30 & MMSI destication to ACK \\\\ \hline 556 SeqID3 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 557 DestID4 & 30 & MMSI destication to ACK \\\\ \hline 558 SeqID4 & 2 & Sequence ID of the message to be acknowledged\\\\ \\hline \\hline 559 Total bits & 167 & Appears to take 1 slot with 1 pad bits to fill the last slot \\\\ \\hline 560 \\end{tabular} 561 \\caption{AIS message number 8: Binary acknowledgement of addressed message} 562 \\label{tab:binack} 563 \\end{table} 564 ''')

565 566 ###################################################################### 567 # Text Definition 568 ###################################################################### 569

570 -def textDefinitionTable(outfile=sys.stdout 571 ,delim='\t' 572 ):

573 ''' 574 Return the text definition table for this message type 575 @param outfile: file like object to print to. 576 @type outfile: file obj 577 @return: text table string via the outfile 578 @rtype: str 579 580 ''' 581 o = outfile 582 o.write('''Parameter'''+delim+'Number of bits'''+delim+'''Description 583 MessageID'''+delim+'''6'''+delim+'''AIS message number. Must be 7 584 RepeatIndicator'''+delim+'''2'''+delim+'''Indicated how many times a message has been repeated 585 UserID'''+delim+'''30'''+delim+'''Unique ship identification number (MMSI). Also known as the Source ID 586 Spare'''+delim+'''1'''+delim+'''Not used. Should be set to zero. 587 DestID1'''+delim+'''30'''+delim+'''MMSI destication to ACK 588 SeqID1'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 589 DestID2'''+delim+'''30'''+delim+'''MMSI destication to ACK 590 SeqID2'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 591 DestID3'''+delim+'''30'''+delim+'''MMSI destication to ACK 592 SeqID3'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 593 DestID4'''+delim+'''30'''+delim+'''MMSI destication to ACK 594 SeqID4'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 595 Total bits'''+delim+'''167'''+delim+'''Appears to take 1 slot with 1 pad bits to fill the last slot''')

596 597 598 ###################################################################### 599 # UNIT TESTING 600 ###################################################################### 601 import unittest

602 -def testParams():

603 '''Return a params file base on the testvalue tags. 604 @rtype: dict 605 @return: params based on testvalue tags 606 ''' 607 params = {} 608 params['MessageID'] = 7 609 params['RepeatIndicator'] = 1 610 params['UserID'] = 1193046 611 params['Spare'] = 0 612 params['DestID1'] = 1193001 613 params['SeqID1'] = 1 614 params['DestID2'] = 1193002 615 params['SeqID2'] = 2 616 params['DestID3'] = 1193003 617 params['SeqID3'] = 3 618 params['DestID4'] = 1193004 619 params['SeqID4'] = 0 620 621 return params

622

623 -class Testbinack(unittest.TestCase):

624 '''Use testvalue tag text from each type to build test case the binack message'''

625 - def testEncodeDecode(self):

626 627 params = testParams() 628 bits = encode(params) 629 r = decode(bits) 630 631 # Check that each parameter came through ok. 632 self.failUnlessEqual(r['MessageID'],params['MessageID']) 633 self.failUnlessEqual(r['RepeatIndicator'],params['RepeatIndicator']) 634 self.failUnlessEqual(r['UserID'],params['UserID']) 635 self.failUnlessEqual(r['Spare'],params['Spare']) 636 self.failUnlessEqual(r['DestID1'],params['DestID1']) 637 self.failUnlessEqual(r['SeqID1'],params['SeqID1']) 638 self.failUnlessEqual(r['DestID2'],params['DestID2']) 639 self.failUnlessEqual(r['SeqID2'],params['SeqID2']) 640 self.failUnlessEqual(r['DestID3'],params['DestID3']) 641 self.failUnlessEqual(r['SeqID3'],params['SeqID3']) 642 self.failUnlessEqual(r['DestID4'],params['DestID4']) 643 self.failUnlessEqual(r['SeqID4'],params['SeqID4'])

644

645 -def addMsgOptions(parser):

646 parser.add_option('-d','--decode',dest='doDecode',default=False,action='store_true', 647 help='decode a "binack" AIS message') 648 parser.add_option('-e','--encode',dest='doEncode',default=False,action='store_true', 649 help='encode a "binack" AIS message') 650 parser.add_option('--RepeatIndicator-field', dest='RepeatIndicatorField',default=0,metavar='uint',type='int' 651 ,help='Field parameter value [default: %default]') 652 parser.add_option('--UserID-field', dest='UserIDField',metavar='uint',type='int' 653 ,help='Field parameter value [default: %default]') 654 parser.add_option('--DestID1-field', dest='DestID1Field',metavar='uint',type='int' 655 ,help='Field parameter value [default: %default]') 656 parser.add_option('--SeqID1-field', dest='SeqID1Field',metavar='uint',type='int' 657 ,help='Field parameter value [default: %default]') 658 parser.add_option('--DestID2-field', dest='DestID2Field',metavar='uint',type='int' 659 ,help='Field parameter value [default: %default]') 660 parser.add_option('--SeqID2-field', dest='SeqID2Field',metavar='uint',type='int' 661 ,help='Field parameter value [default: %default]') 662 parser.add_option('--DestID3-field', dest='DestID3Field',metavar='uint',type='int' 663 ,help='Field parameter value [default: %default]') 664 parser.add_option('--SeqID3-field', dest='SeqID3Field',metavar='uint',type='int' 665 ,help='Field parameter value [default: %default]') 666 parser.add_option('--DestID4-field', dest='DestID4Field',metavar='uint',type='int' 667 ,help='Field parameter value [default: %default]') 668 parser.add_option('--SeqID4-field', dest='SeqID4Field',metavar='uint',type='int' 669 ,help='Field parameter value [default: %default]')

670 671 ############################################################ 672 if __name__=='__main__': 673 674 from optparse import OptionParser 675 parser = OptionParser(usage="%prog [options]", 676 version="%prog "+__version__) 677 678 parser.add_option('--doc-test',dest='doctest',default=False,action='store_true', 679 help='run the documentation tests') 680 parser.add_option('--unit-test',dest='unittest',default=False,action='store_true', 681 help='run the unit tests') 682 parser.add_option('-v','--verbose',dest='verbose',default=False,action='store_true', 683 help='Make the test output verbose') 684 685 # FIX: remove nmea from binary messages. No way to build the whole packet? 686 # FIX: or build the surrounding msg 8 for a broadcast? 687 typeChoices = ('binary','nmeapayload','nmea') # FIX: what about a USCG type message? 688 parser.add_option('-t','--type',choices=typeChoices,type='choice',dest='ioType' 689 ,default='nmeapayload' 690 ,help='What kind of string to write for encoding ('+', '.join(typeChoices)+') [default: %default]') 691 692 693 outputChoices = ('std','html','csv','sql' ) 694 parser.add_option('-T','--output-type',choices=outputChoices,type='choice',dest='outputType' 695 ,default='std' 696 ,help='What kind of string to output ('+', '.join(outputChoices)+') [default: %default]') 697 698 parser.add_option('-o','--output',dest='outputFileName',default=None, 699 help='Name of the python file to write [default: stdout]') 700 701 parser.add_option('-f','--fields',dest='fieldList',default=None, action='append', 702 choices=fieldList, 703 help='Which fields to include in the output. Currently only for csv output [default: all]') 704 705 parser.add_option('-p','--print-csv-field-list',dest='printCsvfieldList',default=False,action='store_true', 706 help='Print the field name for csv') 707 708 parser.add_option('-c','--sql-create',dest='sqlCreate',default=False,action='store_true', 709 help='Print out an sql create command for the table.') 710 711 parser.add_option('--latex-table',dest='latexDefinitionTable',default=False,action='store_true', 712 help='Print a LaTeX table of the type') 713 714 parser.add_option('--text-table',dest='textDefinitionTable',default=False,action='store_true', 715 help='Print delimited table of the type (for Word table importing)') 716 parser.add_option('--delimt-text-table',dest='delimTextDefinitionTable',default='\t' 717 ,help='Delimiter for text table [default: \'%default\'](for Word table importing)') 718 719 720 dbChoices = ('sqlite','postgres') 721 parser.add_option('-D','--db-type',dest='dbType',default='postgres' 722 ,choices=dbChoices,type='choice' 723 ,help='What kind of database ('+', '.join(dbChoices)+') [default: %default]') 724 725 addMsgOptions(parser) 726 727 (options,args) = parser.parse_args() 728 success=True 729 730 if options.doctest: 731 import os; print os.path.basename(sys.argv[0]), 'doctests ...', 732 sys.argv= [sys.argv[0]] 733 if options.verbose: sys.argv.append('-v') 734 import doctest 735 numfail,numtests=doctest.testmod() 736 if numfail==0: print 'ok' 737 else: 738 print 'FAILED' 739 success=False 740 741 if not success: sys.exit('Something Failed') 742 del success # Hide success from epydoc 743 744 if options.unittest: 745 sys.argv = [sys.argv[0]] 746 if options.verbose: sys.argv.append('-v') 747 unittest.main() 748 749 outfile = sys.stdout 750 if None!=options.outputFileName: 751 outfile = file(options.outputFileName,'w') 752 753 754 if options.doEncode: 755 # First make sure all non required options are specified 756 if None==options.RepeatIndicatorField: parser.error("missing value for RepeatIndicatorField") 757 if None==options.UserIDField: parser.error("missing value for UserIDField") 758 if None==options.DestID1Field: parser.error("missing value for DestID1Field") 759 if None==options.SeqID1Field: parser.error("missing value for SeqID1Field") 760 if None==options.DestID2Field: parser.error("missing value for DestID2Field") 761 if None==options.SeqID2Field: parser.error("missing value for SeqID2Field") 762 if None==options.DestID3Field: parser.error("missing value for DestID3Field") 763 if None==options.SeqID3Field: parser.error("missing value for SeqID3Field") 764 if None==options.DestID4Field: parser.error("missing value for DestID4Field") 765 if None==options.SeqID4Field: parser.error("missing value for SeqID4Field") 766 msgDict={ 767 'MessageID': '7', 768 'RepeatIndicator': options.RepeatIndicatorField, 769 'UserID': options.UserIDField, 770 'Spare': '0', 771 'DestID1': options.DestID1Field, 772 'SeqID1': options.SeqID1Field, 773 'DestID2': options.DestID2Field, 774 'SeqID2': options.SeqID2Field, 775 'DestID3': options.DestID3Field, 776 'SeqID3': options.SeqID3Field, 777 'DestID4': options.DestID4Field, 778 'SeqID4': options.SeqID4Field, 779 } 780 781 bits = encode(msgDict) 782 if 'binary'==options.ioType: print str(bits) 783 elif 'nmeapayload'==options.ioType: 784 # FIX: figure out if this might be necessary at compile time 785 print "bitLen",len(bits) 786 bitLen=len(bits) 787 if bitLen%6!=0: 788 bits = bits + BitVector(size=(6 - (bitLen%6))) # Pad out to multiple of 6 789 print "result:",binary.bitvectoais6(bits)[0] 790 791 792 # FIX: Do not emit this option for the binary message payloads. Does not make sense. 793 elif 'nmea'==options.ioType: sys.exit("FIX: need to implement this capability") 794 else: sys.exit('ERROR: unknown ioType. Help!') 795 796 797 if options.sqlCreate: 798 sqlCreateStr(outfile,options.fieldList,dbType=options.dbType) 799 800 if options.latexDefinitionTable: 801 latexDefinitionTable(outfile) 802 803 # For conversion to word tables 804 if options.textDefinitionTable: 805 textDefinitionTable(outfile,options.delimTextDefinitionTable) 806 807 if options.printCsvfieldList: 808 # Make a csv separated list of fields that will be displayed for csv 809 if None == options.fieldList: options.fieldList = fieldList 810 import StringIO 811 buf = StringIO.StringIO() 812 for field in options.fieldList: 813 buf.write(field+',') 814 result = buf.getvalue() 815 if result[-1] == ',': print result[:-1] 816 else: print result 817 818 if options.doDecode: 819 if len(args)==0: args = sys.stdin 820 for msg in args: 821 bv = None 822 823 if msg[0] in ('$','!') and msg[3:6] in ('VDM','VDO'): 824 # Found nmea 825 # FIX: do checksum 826 bv = binary.ais6tobitvec(msg.split(',')[5]) 827 else: # either binary or nmeapayload... expect mostly nmeapayloads 828 # assumes that an all 0 and 1 string can not be a nmeapayload 829 binaryMsg=True 830 for c in msg: 831 if c not in ('0','1'): 832 binaryMsg=False 833 break 834 if binaryMsg: 835 bv = BitVector(bitstring=msg) 836 else: # nmeapayload 837 bv = binary.ais6tobitvec(msg) 838 839 printFields(decode(bv) 840 ,out=outfile 841 ,format=options.outputType 842 ,fieldList=options.fieldList 843 ,dbType=options.dbType 844 ) 845

Source Code for Module ais.ais_msg_7