ais.ais_msg

1 #!/usr/bin/env python 2 3 __version__ = '$Revision: 4791 $'.split()[1] 4 __date__ = '$Date: 2008-01-09 $'.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 dbTableName='binack' 399 'Database table name' 400

401 -def sqlCreateStr(outfile=sys.stdout, fields=None, extraFields=None 402 ,addCoastGuardFields=True 403 ,dbType='postgres' 404 ):

405 ''' 406 Return the SQL CREATE command for this message type 407 @param outfile: file like object to print to. 408 @param fields: which fields to put in the create. Defaults to all. 409 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 410 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 411 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 412 @type addCoastGuardFields: bool 413 @return: sql create string 414 @rtype: str 415 416 @see: sqlCreate 417 ''' 418 # FIX: should this sqlCreate be the same as in LaTeX (createFuncName) rather than hard coded? 419 outfile.write(str(sqlCreate(fields,extraFields,addCoastGuardFields,dbType=dbType)))

420

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

422 ''' 423 Return the sqlhelp object to create the table. 424 425 @param fields: which fields to put in the create. Defaults to all. 426 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 427 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 428 @type addCoastGuardFields: bool 429 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 430 @return: An object that can be used to generate a return 431 @rtype: sqlhelp.create 432 ''' 433 if None == fields: fields = fieldList 434 import sqlhelp 435 c = sqlhelp.create('binack',dbType=dbType) 436 c.addPrimaryKey() 437 if 'MessageID' in fields: c.addInt ('MessageID') 438 if 'RepeatIndicator' in fields: c.addInt ('RepeatIndicator') 439 if 'UserID' in fields: c.addInt ('UserID') 440 if 'Spare' in fields: c.addInt ('Spare') 441 if 'DestID1' in fields: c.addInt ('DestID1') 442 if 'SeqID1' in fields: c.addInt ('SeqID1') 443 if 'DestID2' in fields: c.addInt ('DestID2') 444 if 'SeqID2' in fields: c.addInt ('SeqID2') 445 if 'DestID3' in fields: c.addInt ('DestID3') 446 if 'SeqID3' in fields: c.addInt ('SeqID3') 447 if 'DestID4' in fields: c.addInt ('DestID4') 448 if 'SeqID4' in fields: c.addInt ('SeqID4') 449 450 if addCoastGuardFields: 451 # c.addInt('cg_rssi') # Relative signal strength indicator 452 # c.addInt('cg_d') # dBm receive strength 453 # c.addInt('cg_T') # Receive timestamp from the AIS equipment 454 # c.addInt('cg_S') # Slot received in 455 # c.addVarChar('cg_x',10) # Idonno 456 c.addVarChar('cg_r',15) # Receiver station ID - should usually be an MMSI, but sometimes is a string 457 c.addInt('cg_sec') # UTC seconds since the epoch 458 459 c.addTimestamp('cg_timestamp') # UTC decoded cg_sec - not actually in the data stream 460 461 return c

462

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

464 ''' 465 Return the SQL INSERT command for this message type 466 @param params: dictionary of values keyed by field name 467 @param outfile: file like object to print to. 468 @param extraParams: A sequence of tuples containing (name,sql type) for additional fields 469 @return: sql create string 470 @rtype: str 471 472 @see: sqlCreate 473 ''' 474 outfile.write(str(sqlInsert(params,extraParams,dbType=dbType)))

475 476

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

478 ''' 479 Give the SQL INSERT statement 480 @param params: dict keyed by field name of values 481 @param extraParams: any extra fields that you have created beyond the normal ais message fields 482 @rtype: sqlhelp.insert 483 @return: insert class instance 484 @todo: allow optional type checking of params? 485 @warning: this will take invalid keys happily and do what??? 486 ''' 487 import sqlhelp 488 i = sqlhelp.insert('binack',dbType=dbType) 489 490 if dbType=='postgres': 491 finished = [] 492 for key in params: 493 if key in finished: 494 continue 495 496 if key not in toPgFields and key not in fromPgFields: 497 if type(params[key])==Decimal: i.add(key,float(params[key])) 498 else: i.add(key,params[key]) 499 else: 500 if key in fromPgFields: 501 val = params[key] 502 # Had better be a WKT type like POINT(-88.1 30.321) 503 i.addPostGIS(key,val) 504 finished.append(key) 505 else: 506 # Need to construct the type. 507 pgName = toPgFields[key] 508 #valStr='GeomFromText(\''+pgTypes[pgName]+'(' 509 valStr=pgTypes[pgName]+'(' 510 vals = [] 511 for nonPgKey in fromPgFields[pgName]: 512 vals.append(str(params[nonPgKey])) 513 finished.append(nonPgKey) 514 valStr+=' '.join(vals)+')' 515 i.addPostGIS(pgName,valStr) 516 else: 517 for key in params: 518 if type(params[key])==Decimal: i.add(key,float(params[key])) 519 else: i.add(key,params[key]) 520 521 if None != extraParams: 522 for key in extraParams: 523 i.add(key,extraParams[key]) 524 525 return i

526 527 ###################################################################### 528 # LATEX SUPPORT 529 ###################################################################### 530

531 -def latexDefinitionTable(outfile=sys.stdout 532 ):

533 ''' 534 Return the LaTeX definition table for this message type 535 @param outfile: file like object to print to. 536 @type outfile: file obj 537 @return: LaTeX table string via the outfile 538 @rtype: str 539 540 ''' 541 o = outfile 542 543 o.write(''' 544 \\begin{table}%[htb] 545 \\centering 546 \\begin{tabular}{|l|c|l|} 547 \\hline 548 Parameter & Number of bits & Description 549 \\\\ \\hline\\hline 550 MessageID & 6 & AIS message number. Must be 7 \\\\ \hline 551 RepeatIndicator & 2 & Indicated how many times a message has been repeated \\\\ \hline 552 UserID & 30 & Unique ship identification number (MMSI). Also known as the Source ID \\\\ \hline 553 Spare & 1 & Not used. Should be set to zero. \\\\ \hline 554 DestID1 & 30 & MMSI destication to ACK \\\\ \hline 555 SeqID1 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 556 DestID2 & 30 & MMSI destication to ACK \\\\ \hline 557 SeqID2 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 558 DestID3 & 30 & MMSI destication to ACK \\\\ \hline 559 SeqID3 & 2 & Sequence ID of the message to be acknowledged \\\\ \hline 560 DestID4 & 30 & MMSI destication to ACK \\\\ \hline 561 SeqID4 & 2 & Sequence ID of the message to be acknowledged\\\\ \\hline \\hline 562 Total bits & 167 & Appears to take 1 slot with 1 pad bits to fill the last slot \\\\ \\hline 563 \\end{tabular} 564 \\caption{AIS message number 8: Binary acknowledgement of addressed message} 565 \\label{tab:binack} 566 \\end{table} 567 ''')

568 569 ###################################################################### 570 # Text Definition 571 ###################################################################### 572

573 -def textDefinitionTable(outfile=sys.stdout 574 ,delim='\t' 575 ):

576 ''' 577 Return the text definition table for this message type 578 @param outfile: file like object to print to. 579 @type outfile: file obj 580 @return: text table string via the outfile 581 @rtype: str 582 583 ''' 584 o = outfile 585 o.write('''Parameter'''+delim+'Number of bits'''+delim+'''Description 586 MessageID'''+delim+'''6'''+delim+'''AIS message number. Must be 7 587 RepeatIndicator'''+delim+'''2'''+delim+'''Indicated how many times a message has been repeated 588 UserID'''+delim+'''30'''+delim+'''Unique ship identification number (MMSI). Also known as the Source ID 589 Spare'''+delim+'''1'''+delim+'''Not used. Should be set to zero. 590 DestID1'''+delim+'''30'''+delim+'''MMSI destication to ACK 591 SeqID1'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 592 DestID2'''+delim+'''30'''+delim+'''MMSI destication to ACK 593 SeqID2'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 594 DestID3'''+delim+'''30'''+delim+'''MMSI destication to ACK 595 SeqID3'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 596 DestID4'''+delim+'''30'''+delim+'''MMSI destication to ACK 597 SeqID4'''+delim+'''2'''+delim+'''Sequence ID of the message to be acknowledged 598 Total bits'''+delim+'''167'''+delim+'''Appears to take 1 slot with 1 pad bits to fill the last slot''')

599 600 601 ###################################################################### 602 # UNIT TESTING 603 ###################################################################### 604 import unittest

605 -def testParams():

606 '''Return a params file base on the testvalue tags. 607 @rtype: dict 608 @return: params based on testvalue tags 609 ''' 610 params = {} 611 params['MessageID'] = 7 612 params['RepeatIndicator'] = 1 613 params['UserID'] = 1193046 614 params['Spare'] = 0 615 params['DestID1'] = 1193001 616 params['SeqID1'] = 1 617 params['DestID2'] = 1193002 618 params['SeqID2'] = 2 619 params['DestID3'] = 1193003 620 params['SeqID3'] = 3 621 params['DestID4'] = 1193004 622 params['SeqID4'] = 0 623 624 return params

625

626 -class Testbinack(unittest.TestCase):

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

628 - def testEncodeDecode(self):

629 630 params = testParams() 631 bits = encode(params) 632 r = decode(bits) 633 634 # Check that each parameter came through ok. 635 self.failUnlessEqual(r['MessageID'],params['MessageID']) 636 self.failUnlessEqual(r['RepeatIndicator'],params['RepeatIndicator']) 637 self.failUnlessEqual(r['UserID'],params['UserID']) 638 self.failUnlessEqual(r['Spare'],params['Spare']) 639 self.failUnlessEqual(r['DestID1'],params['DestID1']) 640 self.failUnlessEqual(r['SeqID1'],params['SeqID1']) 641 self.failUnlessEqual(r['DestID2'],params['DestID2']) 642 self.failUnlessEqual(r['SeqID2'],params['SeqID2']) 643 self.failUnlessEqual(r['DestID3'],params['DestID3']) 644 self.failUnlessEqual(r['SeqID3'],params['SeqID3']) 645 self.failUnlessEqual(r['DestID4'],params['DestID4']) 646 self.failUnlessEqual(r['SeqID4'],params['SeqID4'])

647

648 -def addMsgOptions(parser):

649 parser.add_option('-d','--decode',dest='doDecode',default=False,action='store_true', 650 help='decode a "binack" AIS message') 651 parser.add_option('-e','--encode',dest='doEncode',default=False,action='store_true', 652 help='encode a "binack" AIS message') 653 parser.add_option('--RepeatIndicator-field', dest='RepeatIndicatorField',default=0,metavar='uint',type='int' 654 ,help='Field parameter value [default: %default]') 655 parser.add_option('--UserID-field', dest='UserIDField',metavar='uint',type='int' 656 ,help='Field parameter value [default: %default]') 657 parser.add_option('--DestID1-field', dest='DestID1Field',metavar='uint',type='int' 658 ,help='Field parameter value [default: %default]') 659 parser.add_option('--SeqID1-field', dest='SeqID1Field',metavar='uint',type='int' 660 ,help='Field parameter value [default: %default]') 661 parser.add_option('--DestID2-field', dest='DestID2Field',metavar='uint',type='int' 662 ,help='Field parameter value [default: %default]') 663 parser.add_option('--SeqID2-field', dest='SeqID2Field',metavar='uint',type='int' 664 ,help='Field parameter value [default: %default]') 665 parser.add_option('--DestID3-field', dest='DestID3Field',metavar='uint',type='int' 666 ,help='Field parameter value [default: %default]') 667 parser.add_option('--SeqID3-field', dest='SeqID3Field',metavar='uint',type='int' 668 ,help='Field parameter value [default: %default]') 669 parser.add_option('--DestID4-field', dest='DestID4Field',metavar='uint',type='int' 670 ,help='Field parameter value [default: %default]') 671 parser.add_option('--SeqID4-field', dest='SeqID4Field',metavar='uint',type='int' 672 ,help='Field parameter value [default: %default]')

673 674 ############################################################ 675 if __name__=='__main__': 676 677 from optparse import OptionParser 678 parser = OptionParser(usage="%prog [options]", 679 version="%prog "+__version__) 680 681 parser.add_option('--doc-test',dest='doctest',default=False,action='store_true', 682 help='run the documentation tests') 683 parser.add_option('--unit-test',dest='unittest',default=False,action='store_true', 684 help='run the unit tests') 685 parser.add_option('-v','--verbose',dest='verbose',default=False,action='store_true', 686 help='Make the test output verbose') 687 688 # FIX: remove nmea from binary messages. No way to build the whole packet? 689 # FIX: or build the surrounding msg 8 for a broadcast? 690 typeChoices = ('binary','nmeapayload','nmea') # FIX: what about a USCG type message? 691 parser.add_option('-t','--type',choices=typeChoices,type='choice',dest='ioType' 692 ,default='nmeapayload' 693 ,help='What kind of string to write for encoding ('+', '.join(typeChoices)+') [default: %default]') 694 695 696 outputChoices = ('std','html','csv','sql' ) 697 parser.add_option('-T','--output-type',choices=outputChoices,type='choice',dest='outputType' 698 ,default='std' 699 ,help='What kind of string to output ('+', '.join(outputChoices)+') [default: %default]') 700 701 parser.add_option('-o','--output',dest='outputFileName',default=None, 702 help='Name of the python file to write [default: stdout]') 703 704 parser.add_option('-f','--fields',dest='fieldList',default=None, action='append', 705 choices=fieldList, 706 help='Which fields to include in the output. Currently only for csv output [default: all]') 707 708 parser.add_option('-p','--print-csv-field-list',dest='printCsvfieldList',default=False,action='store_true', 709 help='Print the field name for csv') 710 711 parser.add_option('-c','--sql-create',dest='sqlCreate',default=False,action='store_true', 712 help='Print out an sql create command for the table.') 713 714 parser.add_option('--latex-table',dest='latexDefinitionTable',default=False,action='store_true', 715 help='Print a LaTeX table of the type') 716 717 parser.add_option('--text-table',dest='textDefinitionTable',default=False,action='store_true', 718 help='Print delimited table of the type (for Word table importing)') 719 parser.add_option('--delimt-text-table',dest='delimTextDefinitionTable',default='\t' 720 ,help='Delimiter for text table [default: \'%default\'](for Word table importing)') 721 722 723 dbChoices = ('sqlite','postgres') 724 parser.add_option('-D','--db-type',dest='dbType',default='postgres' 725 ,choices=dbChoices,type='choice' 726 ,help='What kind of database ('+', '.join(dbChoices)+') [default: %default]') 727 728 addMsgOptions(parser) 729 730 (options,args) = parser.parse_args() 731 success=True 732 733 if options.doctest: 734 import os; print os.path.basename(sys.argv[0]), 'doctests ...', 735 sys.argv= [sys.argv[0]] 736 if options.verbose: sys.argv.append('-v') 737 import doctest 738 numfail,numtests=doctest.testmod() 739 if numfail==0: print 'ok' 740 else: 741 print 'FAILED' 742 success=False 743 744 if not success: sys.exit('Something Failed') 745 del success # Hide success from epydoc 746 747 if options.unittest: 748 sys.argv = [sys.argv[0]] 749 if options.verbose: sys.argv.append('-v') 750 unittest.main() 751 752 outfile = sys.stdout 753 if None!=options.outputFileName: 754 outfile = file(options.outputFileName,'w') 755 756 757 if options.doEncode: 758 # First make sure all non required options are specified 759 if None==options.RepeatIndicatorField: parser.error("missing value for RepeatIndicatorField") 760 if None==options.UserIDField: parser.error("missing value for UserIDField") 761 if None==options.DestID1Field: parser.error("missing value for DestID1Field") 762 if None==options.SeqID1Field: parser.error("missing value for SeqID1Field") 763 if None==options.DestID2Field: parser.error("missing value for DestID2Field") 764 if None==options.SeqID2Field: parser.error("missing value for SeqID2Field") 765 if None==options.DestID3Field: parser.error("missing value for DestID3Field") 766 if None==options.SeqID3Field: parser.error("missing value for SeqID3Field") 767 if None==options.DestID4Field: parser.error("missing value for DestID4Field") 768 if None==options.SeqID4Field: parser.error("missing value for SeqID4Field") 769 msgDict={ 770 'MessageID': '7', 771 'RepeatIndicator': options.RepeatIndicatorField, 772 'UserID': options.UserIDField, 773 'Spare': '0', 774 'DestID1': options.DestID1Field, 775 'SeqID1': options.SeqID1Field, 776 'DestID2': options.DestID2Field, 777 'SeqID2': options.SeqID2Field, 778 'DestID3': options.DestID3Field, 779 'SeqID3': options.SeqID3Field, 780 'DestID4': options.DestID4Field, 781 'SeqID4': options.SeqID4Field, 782 } 783 784 bits = encode(msgDict) 785 if 'binary'==options.ioType: print str(bits) 786 elif 'nmeapayload'==options.ioType: 787 # FIX: figure out if this might be necessary at compile time 788 print "bitLen",len(bits) 789 bitLen=len(bits) 790 if bitLen%6!=0: 791 bits = bits + BitVector(size=(6 - (bitLen%6))) # Pad out to multiple of 6 792 print "result:",binary.bitvectoais6(bits)[0] 793 794 795 # FIX: Do not emit this option for the binary message payloads. Does not make sense. 796 elif 'nmea'==options.ioType: sys.exit("FIX: need to implement this capability") 797 else: sys.exit('ERROR: unknown ioType. Help!') 798 799 800 if options.sqlCreate: 801 sqlCreateStr(outfile,options.fieldList,dbType=options.dbType) 802 803 if options.latexDefinitionTable: 804 latexDefinitionTable(outfile) 805 806 # For conversion to word tables 807 if options.textDefinitionTable: 808 textDefinitionTable(outfile,options.delimTextDefinitionTable) 809 810 if options.printCsvfieldList: 811 # Make a csv separated list of fields that will be displayed for csv 812 if None == options.fieldList: options.fieldList = fieldList 813 import StringIO 814 buf = StringIO.StringIO() 815 for field in options.fieldList: 816 buf.write(field+',') 817 result = buf.getvalue() 818 if result[-1] == ',': print result[:-1] 819 else: print result 820 821 if options.doDecode: 822 if len(args)==0: args = sys.stdin 823 for msg in args: 824 bv = None 825 826 if msg[0] in ('$','!') and msg[3:6] in ('VDM','VDO'): 827 # Found nmea 828 # FIX: do checksum 829 bv = binary.ais6tobitvec(msg.split(',')[5]) 830 else: # either binary or nmeapayload... expect mostly nmeapayloads 831 # assumes that an all 0 and 1 string can not be a nmeapayload 832 binaryMsg=True 833 for c in msg: 834 if c not in ('0','1'): 835 binaryMsg=False 836 break 837 if binaryMsg: 838 bv = BitVector(bitstring=msg) 839 else: # nmeapayload 840 bv = binary.ais6tobitvec(msg) 841 842 printFields(decode(bv) 843 ,out=outfile 844 ,format=options.outputType 845 ,fieldList=options.fieldList 846 ,dbType=options.dbType 847 ) 848

Source Code for Module ais.ais_msg_7