Package ais :: Module ais_msg_8
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Source Code for Module ais.ais_msg_8

  1  #!/usr/bin/env python 
  2   
  3  __version__ = '$Revision: 4791 $'.split()[1] 
  4  __date__ = '$Date: 2007-02-26 $'.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          'BinaryData', 
 55  ) 
 56   
 57  fieldListPostgres = ( 
 58          'MessageID', 
 59          'RepeatIndicator', 
 60          'UserID', 
 61          'Spare', 
 62          'BinaryData', 
 63  ) 
 64   
 65  toPgFields = { 
 66  } 
 67  ''' 
 68  Go to the Postgis field names from the straight field name 
 69  ''' 
 70   
 71  fromPgFields = { 
 72  } 
 73  ''' 
 74  Go from the Postgis field names to the straight field name 
 75  ''' 
 76   
 77  pgTypes = { 
 78  } 
 79  ''' 
 80  Lookup table for each postgis field name to get its type. 
 81  ''' 
 82   
83 -def encode(params, validate=False):
84 '''Create a bin_broadcast binary message payload to pack into an AIS Msg bin_broadcast. 85 86 Fields in params: 87 - MessageID(uint): AIS message number. Must be 8 (field automatically set to "8") 88 - RepeatIndicator(uint): Indicated how many times a message has been repeated 89 - UserID(uint): Unique ship identification number (MMSI) 90 - Spare(uint): Reserved for definition by a regional authority. (field automatically set to "0") 91 - BinaryData(binary): Bits for a binary broadcast message 92 @param params: Dictionary of field names/values. Throws a ValueError exception if required is missing 93 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 94 @rtype: BitVector 95 @return: encoded binary message (for binary messages, this needs to be wrapped in a msg 8 96 @note: The returned bits may not be 6 bit aligned. It is up to you to pad out the bits. 97 ''' 98 99 bvList = [] 100 bvList.append(binary.setBitVectorSize(BitVector(intVal=8),6)) 101 if 'RepeatIndicator' in params: 102 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['RepeatIndicator']),2)) 103 else: 104 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),2)) 105 bvList.append(binary.setBitVectorSize(BitVector(intVal=params['UserID']),30)) 106 bvList.append(binary.setBitVectorSize(BitVector(intVal=0),2)) 107 bvList.append(params['BinaryData']) 108 109 return binary.joinBV(bvList)
110
111 -def decode(bv, validate=False):
112 '''Unpack a bin_broadcast message 113 114 Fields in params: 115 - MessageID(uint): AIS message number. Must be 8 (field automatically set to "8") 116 - RepeatIndicator(uint): Indicated how many times a message has been repeated 117 - UserID(uint): Unique ship identification number (MMSI) 118 - Spare(uint): Reserved for definition by a regional authority. (field automatically set to "0") 119 - BinaryData(binary): Bits for a binary broadcast message 120 @type bv: BitVector 121 @param bv: Bits defining a message 122 @param validate: Set to true to cause checking to occur. Runs slower. FIX: not implemented. 123 @rtype: dict 124 @return: params 125 ''' 126 127 #Would be nice to check the bit count here.. 128 #if validate: 129 # assert (len(bv)==FIX: SOME NUMBER) 130 r = {} 131 r['MessageID']=8 132 r['RepeatIndicator']=int(bv[6:8]) 133 r['UserID']=int(bv[8:38]) 134 r['Spare']=0 135 r['BinaryData']=bv[40:] 136 return r
137
138 -def decodeMessageID(bv, validate=False):
139 return 8
140
141 -def decodeRepeatIndicator(bv, validate=False):
142 return int(bv[6:8])
143
144 -def decodeUserID(bv, validate=False):
145 return int(bv[8:38])
146
147 -def decodeSpare(bv, validate=False):
148 return 0
149
150 -def decodeBinaryData(bv, validate=False):
151 return bv[40:]
152 153
154 -def printHtml(params, out=sys.stdout):
155 out.write("<h3>bin_broadcast<h3>\n") 156 out.write("<table border=\"1\">\n") 157 out.write("<tr bgcolor=\"orange\">\n") 158 out.write("<th align=\"left\">Field Name</th>\n") 159 out.write("<th align=\"left\">Type</th>\n") 160 out.write("<th align=\"left\">Value</th>\n") 161 out.write("<th align=\"left\">Value in Lookup Table</th>\n") 162 out.write("<th align=\"left\">Units</th>\n") 163 out.write("\n") 164 out.write("<tr>\n") 165 out.write("<td>MessageID</td>\n") 166 out.write("<td>uint</td>\n") 167 if 'MessageID' in params: 168 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 169 out.write(" <td>"+str(params['MessageID'])+"</td>\n") 170 out.write("</tr>\n") 171 out.write("\n") 172 out.write("<tr>\n") 173 out.write("<td>RepeatIndicator</td>\n") 174 out.write("<td>uint</td>\n") 175 if 'RepeatIndicator' in params: 176 out.write(" <td>"+str(params['RepeatIndicator'])+"</td>\n") 177 if str(params['RepeatIndicator']) in RepeatIndicatorDecodeLut: 178 out.write("<td>"+RepeatIndicatorDecodeLut[str(params['RepeatIndicator'])]+"</td>") 179 else: 180 out.write("<td><i>Missing LUT entry</i></td>") 181 out.write("</tr>\n") 182 out.write("\n") 183 out.write("<tr>\n") 184 out.write("<td>UserID</td>\n") 185 out.write("<td>uint</td>\n") 186 if 'UserID' in params: 187 out.write(" <td>"+str(params['UserID'])+"</td>\n") 188 out.write(" <td>"+str(params['UserID'])+"</td>\n") 189 out.write("</tr>\n") 190 out.write("\n") 191 out.write("<tr>\n") 192 out.write("<td>Spare</td>\n") 193 out.write("<td>uint</td>\n") 194 if 'Spare' in params: 195 out.write(" <td>"+str(params['Spare'])+"</td>\n") 196 out.write(" <td>"+str(params['Spare'])+"</td>\n") 197 out.write("</tr>\n") 198 out.write("\n") 199 out.write("<tr>\n") 200 out.write("<td>BinaryData</td>\n") 201 out.write("<td>binary</td>\n") 202 if 'BinaryData' in params: 203 out.write(" <td>"+str(params['BinaryData'])+"</td>\n") 204 out.write(" <td>"+str(params['BinaryData'])+"</td>\n") 205 out.write("</tr>\n") 206 out.write("</table>\n")
207
208 -def printFields(params, out=sys.stdout, format='std', fieldList=None, dbType='postgres'):
209 '''Print a bin_broadcast message to stdout. 210 211 Fields in params: 212 - MessageID(uint): AIS message number. Must be 8 (field automatically set to "8") 213 - RepeatIndicator(uint): Indicated how many times a message has been repeated 214 - UserID(uint): Unique ship identification number (MMSI) 215 - Spare(uint): Reserved for definition by a regional authority. (field automatically set to "0") 216 - BinaryData(binary): Bits for a binary broadcast message 217 @param params: Dictionary of field names/values. 218 @param out: File like object to write to 219 @rtype: stdout 220 @return: text to out 221 ''' 222 223 if 'std'==format: 224 out.write("bin_broadcast:\n") 225 if 'MessageID' in params: out.write(" MessageID: "+str(params['MessageID'])+"\n") 226 if 'RepeatIndicator' in params: out.write(" RepeatIndicator: "+str(params['RepeatIndicator'])+"\n") 227 if 'UserID' in params: out.write(" UserID: "+str(params['UserID'])+"\n") 228 if 'Spare' in params: out.write(" Spare: "+str(params['Spare'])+"\n") 229 if 'BinaryData' in params: out.write(" BinaryData: "+str(params['BinaryData'])+"\n") 230 elif 'csv'==format: 231 if None == options.fieldList: 232 options.fieldList = fieldList 233 needComma = False; 234 for field in fieldList: 235 if needComma: out.write(',') 236 needComma = True 237 if field in params: 238 out.write(str(params[field])) 239 # else: leave it empty 240 out.write("\n") 241 elif 'html'==format: 242 printHtml(params,out) 243 elif 'sql'==format: 244 sqlInsertStr(params,out,dbType=dbType) 245 else: 246 print "ERROR: unknown format:",format 247 assert False 248 249 return # Nothing to return
250 251 RepeatIndicatorEncodeLut = { 252 'default':'0', 253 'do not repeat any more':'3', 254 } #RepeatIndicatorEncodeLut 255 256 RepeatIndicatorDecodeLut = { 257 '0':'default', 258 '3':'do not repeat any more', 259 } # RepeatIndicatorEncodeLut 260 261 ###################################################################### 262 # SQL SUPPORT 263 ###################################################################### 264
265 -def sqlCreateStr(outfile=sys.stdout, fields=None, extraFields=None 266 ,addCoastGuardFields=True 267 ,dbType='postgres' 268 ):
269 ''' 270 Return the SQL CREATE command for this message type 271 @param outfile: file like object to print to. 272 @param fields: which fields to put in the create. Defaults to all. 273 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 274 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 275 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 276 @type addCoastGuardFields: bool 277 @return: sql create string 278 @rtype: str 279 280 @see: sqlCreate 281 ''' 282 outfile.write(str(sqlCreate(fields,extraFields,addCoastGuardFields,dbType=dbType)))
283
284 -def sqlCreate(fields=None, extraFields=None, addCoastGuardFields=True, dbType='postgres'):
285 ''' 286 Return the sqlhelp object to create the table. 287 288 @param fields: which fields to put in the create. Defaults to all. 289 @param extraFields: A sequence of tuples containing (name,sql type) for additional fields 290 @param addCoastGuardFields: Add the extra fields that come after the NMEA check some from the USCG N-AIS format 291 @type addCoastGuardFields: bool 292 @param dbType: Which flavor of database we are using so that the create is tailored ('sqlite' or 'postgres') 293 @return: An object that can be used to generate a return 294 @rtype: sqlhelp.create 295 ''' 296 if None == fields: fields = fieldList 297 import sqlhelp 298 c = sqlhelp.create('bin_broadcast',dbType=dbType) 299 c.addPrimaryKey() 300 if 'MessageID' in fields: c.addInt ('MessageID') 301 if 'RepeatIndicator' in fields: c.addInt ('RepeatIndicator') 302 if 'UserID' in fields: c.addInt ('UserID') 303 if 'Spare' in fields: c.addInt ('Spare') 304 if 'BinaryData' in fields: c.addBitVarying('BinaryData',1024) 305 306 if addCoastGuardFields: 307 # c.addInt('cg_rssi') # Relative signal strength indicator 308 # c.addInt('cg_d') # dBm receive strength 309 # c.addInt('cg_T') # Receive timestamp from the AIS equipment 310 # c.addInt('cg_S') # Slot received in 311 # c.addVarChar('cg_x',10) # Idonno 312 c.addVarChar('cg_r',15) # Receiver station ID - should usually be an MMSI, but sometimes is a string 313 c.addInt('cg_sec') # UTC seconds since the epoch 314 315 c.addTimestamp('cg_timestamp') # UTC decoded cg_sec - not actually in the data stream 316 317 return c
318
319 -def sqlInsertStr(params, outfile=sys.stdout, extraParams=None, dbType='postgres'):
320 ''' 321 Return the SQL INSERT command for this message type 322 @param params: dictionary of values keyed by field name 323 @param outfile: file like object to print to. 324 @param extraParams: A sequence of tuples containing (name,sql type) for additional fields 325 @return: sql create string 326 @rtype: str 327 328 @see: sqlCreate 329 ''' 330 outfile.write(str(sqlInsert(params,extraParams,dbType=dbType)))
331 332
333 -def sqlInsert(params,extraParams=None,dbType='postgres'):
334 ''' 335 Give the SQL INSERT statement 336 @param params: dict keyed by field name of values 337 @param extraParams: any extra fields that you have created beyond the normal ais message fields 338 @rtype: sqlhelp.insert 339 @return: insert class instance 340 @todo: allow optional type checking of params? 341 @warning: this will take invalid keys happily and do what??? 342 ''' 343 import sqlhelp 344 i = sqlhelp.insert('bin_broadcast',dbType=dbType) 345 346 if dbType=='postgres': 347 finished = [] 348 for key in params: 349 if key in finished: 350 continue 351 352 if key not in toPgFields and key not in fromPgFields: 353 if type(params[key])==Decimal: i.add(key,float(params[key])) 354 else: i.add(key,params[key]) 355 else: 356 if key in fromPgFields: 357 val = params[key] 358 # Had better be a WKT type like POINT(-88.1 30.321) 359 i.addPostGIS(key,val) 360 finished.append(key) 361 else: 362 # Need to construct the type. 363 pgName = toPgFields[key] 364 #valStr='GeomFromText(\''+pgTypes[pgName]+'(' 365 valStr=pgTypes[pgName]+'(' 366 vals = [] 367 for nonPgKey in fromPgFields[pgName]: 368 vals.append(str(params[nonPgKey])) 369 finished.append(nonPgKey) 370 valStr+=' '.join(vals)+')' 371 i.addPostGIS(pgName,valStr) 372 else: 373 for key in params: 374 if type(params[key])==Decimal: i.add(key,float(params[key])) 375 else: i.add(key,params[key]) 376 377 if None != extraParams: 378 for key in extraParams: 379 i.add(key,extraParams[key]) 380 381 return i
382 383 384 ###################################################################### 385 # UNIT TESTING 386 ###################################################################### 387 import unittest
388 -def testParams():
389 '''Return a params file base on the testvalue tags. 390 @rtype: dict 391 @return: params based on testvalue tags 392 ''' 393 params = {} 394 params['MessageID'] = 8 395 params['RepeatIndicator'] = 1 396 params['UserID'] = 1193046 397 params['Spare'] = 0 398 params['BinaryData'] = BitVector(bitstring='110000101100000111100010010101001110111001101010011011111111100000110001011100001011111111101111111110011001000000010001110') 399 400 return params
401
402 -class Testbin_broadcast(unittest.TestCase):
403 '''Use testvalue tag text from each type to build test case the bin_broadcast message'''
404 - def testEncodeDecode(self):
405 406 params = testParams() 407 bits = encode(params) 408 r = decode(bits) 409 410 # Check that each parameter came through ok. 411 self.failUnlessEqual(r['MessageID'],params['MessageID']) 412 self.failUnlessEqual(r['RepeatIndicator'],params['RepeatIndicator']) 413 self.failUnlessEqual(r['UserID'],params['UserID']) 414 self.failUnlessEqual(r['Spare'],params['Spare']) 415 self.failUnlessEqual(r['BinaryData'],params['BinaryData'])
416
417 -def addMsgOptions(parser):
418 parser.add_option('-d','--decode',dest='doDecode',default=False,action='store_true', 419 help='decode a "bin_broadcast" AIS message') 420 parser.add_option('-e','--encode',dest='doEncode',default=False,action='store_true', 421 help='encode a "bin_broadcast" AIS message') 422 parser.add_option('--RepeatIndicator-field', dest='RepeatIndicatorField',default=0,metavar='uint',type='int' 423 ,help='Field parameter value [default: %default]') 424 parser.add_option('--UserID-field', dest='UserIDField',metavar='uint',type='int' 425 ,help='Field parameter value [default: %default]') 426 parser.add_option('--BinaryData-field', dest='BinaryDataField',metavar='binary',type='string' 427 ,help='Field parameter value [default: %default]')
428 429 ############################################################ 430 if __name__=='__main__': 431 432 from optparse import OptionParser 433 parser = OptionParser(usage="%prog [options]", 434 version="%prog "+__version__) 435 436 parser.add_option('--doc-test',dest='doctest',default=False,action='store_true', 437 help='run the documentation tests') 438 parser.add_option('--unit-test',dest='unittest',default=False,action='store_true', 439 help='run the unit tests') 440 parser.add_option('-v','--verbose',dest='verbose',default=False,action='store_true', 441 help='Make the test output verbose') 442 443 # FIX: remove nmea from binary messages. No way to build the whole packet? 444 # FIX: or build the surrounding msg 8 for a broadcast? 445 typeChoices = ('binary','nmeapayload','nmea') # FIX: what about a USCG type message? 446 parser.add_option('-t','--type',choices=typeChoices,type='choice',dest='ioType' 447 ,default='nmeapayload' 448 ,help='What kind of string to write for encoding ('+', '.join(typeChoices)+') [default: %default]') 449 450 451 outputChoices = ('std','html','csv','sql' ) 452 parser.add_option('-T','--output-type',choices=outputChoices,type='choice',dest='outputType' 453 ,default='std' 454 ,help='What kind of string to output ('+', '.join(outputChoices)+') [default: %default]') 455 456 parser.add_option('-o','--output',dest='outputFileName',default=None, 457 help='Name of the python file to write [default: stdout]') 458 459 parser.add_option('-f','--fields',dest='fieldList',default=None, action='append', 460 choices=fieldList, 461 help='Which fields to include in the output. Currently only for csv output [default: all]') 462 463 parser.add_option('-p','--print-csv-field-list',dest='printCsvfieldList',default=False,action='store_true', 464 help='Print the field name for csv') 465 466 parser.add_option('-c','--sql-create',dest='sqlCreate',default=False,action='store_true', 467 help='Print out an sql create command for the table.') 468 469 dbChoices = ('sqlite','postgres') 470 parser.add_option('-D','--db-type',dest='dbType',default='postgres' 471 ,choices=dbChoices,type='choice' 472 ,help='What kind of database ('+', '.join(dbChoices)+') [default: %default]') 473 474 addMsgOptions(parser) 475 476 (options,args) = parser.parse_args() 477 success=True 478 479 if options.doctest: 480 import os; print os.path.basename(sys.argv[0]), 'doctests ...', 481 sys.argv= [sys.argv[0]] 482 if options.verbose: sys.argv.append('-v') 483 import doctest 484 numfail,numtests=doctest.testmod() 485 if numfail==0: print 'ok' 486 else: 487 print 'FAILED' 488 success=False 489 490 if not success: sys.exit('Something Failed') 491 del success # Hide success from epydoc 492 493 if options.unittest: 494 sys.argv = [sys.argv[0]] 495 if options.verbose: sys.argv.append('-v') 496 unittest.main() 497 498 outfile = sys.stdout 499 if None!=options.outputFileName: 500 outfile = file(options.outputFileName,'w') 501 502 503 if options.doEncode: 504 # First make sure all non required options are specified 505 if None==options.RepeatIndicatorField: parser.error("missing value for RepeatIndicatorField") 506 if None==options.UserIDField: parser.error("missing value for UserIDField") 507 if None==options.BinaryDataField: parser.error("missing value for BinaryDataField") 508 msgDict={ 509 'MessageID': '8', 510 'RepeatIndicator': options.RepeatIndicatorField, 511 'UserID': options.UserIDField, 512 'Spare': '0', 513 'BinaryData': options.BinaryDataField, 514 } 515 516 bits = encode(msgDict) 517 if 'binary'==options.ioType: print str(bits) 518 elif 'nmeapayload'==options.ioType: 519 # FIX: figure out if this might be necessary at compile time 520 print "bitLen",len(bits) 521 bitLen=len(bits) 522 if bitLen%6!=0: 523 bits = bits + BitVector(size=(6 - (bitLen%6))) # Pad out to multiple of 6 524 print "result:",binary.bitvectoais6(bits)[0] 525 526 527 # FIX: Do not emit this option for the binary message payloads. Does not make sense. 528 elif 'nmea'==options.ioType: sys.exit("FIX: need to implement this capability") 529 else: sys.exit('ERROR: unknown ioType. Help!') 530 531 532 if options.sqlCreate: 533 sqlCreateStr(outfile,options.fieldList,dbType=options.dbType) 534 535 if options.printCsvfieldList: 536 # Make a csv separated list of fields that will be displayed for csv 537 if None == options.fieldList: options.fieldList = fieldList 538 import StringIO 539 buf = StringIO.StringIO() 540 for field in options.fieldList: 541 buf.write(field+',') 542 result = buf.getvalue() 543 if result[-1] == ',': print result[:-1] 544 else: print result 545 546 if options.doDecode: 547 for msg in args: 548 bv = None 549 550 if msg[0] in ('$','!') and msg[3:6] in ('VDM','VDO'): 551 # Found nmea 552 # FIX: do checksum 553 bv = binary.ais6tobitvec(msg.split(',')[5]) 554 else: # either binary or nmeapayload... expect mostly nmeapayloads 555 # assumes that an all 0 and 1 string can not be a nmeapayload 556 binaryMsg=True 557 for c in msg: 558 if c not in ('0','1'): 559 binaryMsg=False 560 break 561 if binaryMsg: 562 bv = BitVector(bitstring=msg) 563 else: # nmeapayload 564 bv = binary.ais6tobitvec(msg) 565 566 printFields(decode(bv) 567 ,out=outfile 568 ,format=options.outputType 569 ,fieldList=options.fieldList 570 ,dbType=options.dbType 571 ) 572