I have an Pythonscript which connects to a Server over a HTTP Connection (and need to listen to the connection).
I guess it should work similar to asyncstreams. I´m not a NEtwork-Pro so i do not know exactly.
The - working - Pythonclient code is:
Can i do this with B4A?
Can i create a http connection where i can listen to the incoming data like in asyncstream and send new requests (GPGGA String) on the connection to get updates answers linke in the Pythin Script above? How i would do it with B4A?
Any help or suggestions regarding this is highly appreciated.
I guess it should work similar to asyncstreams. I´m not a NEtwork-Pro so i do not know exactly.
The - working - Pythonclient code is:
B4X:
#!/usr/bin/python -u
"""
This is heavily based on the NtripPerlClient program written by BKG.
Then heavily based on a unavco original.
"""
import socket
import sys
import datetime
import base64
import time
#import ssl
from optparse import OptionParser
version=0.2
useragent="NTRIP JCMBsoftPythonClient/%.1f" % version
# reconnect parameter (fixed values):
factor=2 # How much the sleep time increases with each failed attempt
maxReconnect=1
maxReconnectTime=1200
sleepTime=1 # So the first one is 1 second
maxConnectTime=0
class NtripClient(object):
def __init__(self,
buffer=50,
user="",
out=sys.stdout,
port=2101,
caster="",
mountpoint="",
host=False,
lat=46,
lon=122,
height=1212,
ssl=False,
verbose=False,
UDP_Port=None,
V2=False,
headerFile=sys.stderr,
headerOutput=False,
):
self.buffer=buffer
self.user=base64.b64encode(user)
self.out=out
self.port=port
self.caster=caster
self.mountpoint=mountpoint
self.setPosition(lat, lon)
self.height=height
self.verbose=verbose
self.ssl=ssl
self.host=host
self.UDP_Port=UDP_Port
self.V2=V2
self.headerFile=headerFile
self.headerOutput=headerOutput
self.maxConnectTime=maxConnectTime
self.socket=None
if UDP_Port:
self.UDP_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
self.UDP_socket.bind(('', 0))
self.UDP_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
else:
self.UDP_socket=None
def setPosition(self, lat, lon):
self.flagN="N"
self.flagE="E"
if lon>180:
lon=(lon-360)*-1
self.flagE="W"
elif (lon<0 and lon>= -180):
lon=lon*-1
self.flagE="W"
elif lon<-180:
lon=lon+360
self.flagE="E"
else:
self.lon=lon
if lat<0:
lat=lat*-1
self.flagN="S"
self.lonDeg=int(lon)
self.latDeg=int(lat)
self.lonMin=(lon-self.lonDeg)*60
self.latMin=(lat-self.latDeg)*60
def getMountPointString(self):
mountPointString = "GET %s HTTP/1.1\r\nUser-Agent: %s\r\nAuthorization: Basic %s\r\n" % (self.mountpoint, useragent, self.user)
# mountPointString = "GET %s HTTP/1.1\r\nUser-Agent: %s\r\n" % (self.mountpoint, useragent)
if self.host or self.V2:
hostString = "Host: %s:%i\r\n" % (self.caster,self.port)
mountPointString+=hostString
if self.V2:
mountPointString+="Ntrip-Version: Ntrip/2.0\r\n"
mountPointString+="\r\n"
if self.verbose:
print mountPointString
return mountPointString
def getGGAString(self):
now = datetime.datetime.utcnow()
ggaString= "GPGGA,%02d%02d%04.2f,%02d%011.8f,%1s,%03d%011.8f,%1s,1,05,0.19,+00400,M,%5.3f,M,," % \
(now.hour,now.minute,now.second,self.latDeg,self.latMin,self.flagN,self.lonDeg,self.lonMin,self.flagE,self.height)
checksum = self.calcultateCheckSum(ggaString)
if self.verbose:
print "$%s*%s\r\n" % (ggaString, checksum)
return "$%s*%s\r\n" % (ggaString, checksum)
def calcultateCheckSum(self, stringToCheck):
xsum_calc = 0
for char in stringToCheck:
xsum_calc = xsum_calc ^ ord(char)
return "%02X" % xsum_calc
def readData(self):
reconnectTry=1
sleepTime=1
reconnectTime=0
if maxConnectTime > 0 :
EndConnect=datetime.timedelta(seconds=maxConnectTime)
try:
while reconnectTry<=maxReconnect:
found_header=False
if self.verbose:
sys.stderr.write('Connection {0} of {1}\n'.format(reconnectTry,maxReconnect))
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if self.ssl:
self.socket=ssl.wrap_socket(self.socket)
error_indicator = self.socket.connect_ex((self.caster, self.port))
if error_indicator==0:
sleepTime = 1
connectTime=datetime.datetime.now()
self.socket.settimeout(10)
self.socket.sendall(self.getMountPointString())
while not found_header:
casterResponse=self.socket.recv(4096) #All the data
header_lines = casterResponse.split("\r\n")
for line in header_lines:
if line=="":
if not found_header:
found_header=True
if self.verbose:
sys.stderr.write("End Of Header"+"\n")
else:
if self.verbose:
sys.stderr.write("Header: " + line+"\n")
if self.headerOutput:
self.headerFile.write(line+"\n")
for line in header_lines:
if line.find("SOURCETABLE")>=0:
sys.stderr.write("Mount point does not exist")
sys.exit(1)
elif line.find("401 Unauthorized")>=0:
sys.stderr.write("Unauthorized request\n")
sys.exit(1)
elif line.find("404 Not Found")>=0:
sys.stderr.write("Mount Point does not exist\n")
sys.exit(2)
elif line.find("ICY 200 OK")>=0:
#Request was valid
self.socket.sendall(self.getGGAString())
elif line.find("HTTP/1.0 200 OK")>=0:
#Request was valid
self.socket.sendall(self.getGGAString())
elif line.find("HTTP/1.1 200 OK")>=0:
#Request was valid
self.socket.sendall(self.getGGAString())
data = "Initial data"
while data:
try:
data=self.socket.recv(self.buffer)
self.out.write(data)
if self.UDP_socket:
self.UDP_socket.sendto(data, ('<broadcast>', self.UDP_Port))
# print datetime.datetime.now()-connectTime
if maxConnectTime :
if datetime.datetime.now() > connectTime+EndConnect:
if self.verbose:
sys.stderr.write("Connection Timed exceeded\n")
sys.exit(0)
except socket.timeout:
if self.verbose:
sys.stderr.write('Connection TimedOut\n')
data=False
except socket.error:
if self.verbose:
sys.stderr.write('Connection Error\n')
data=False
if self.verbose:
sys.stderr.write('Closing Connection\n')
self.socket.close()
self.socket=None
if reconnectTry < maxReconnect :
sys.stderr.write( "%s No Connection to NtripCaster. Trying again in %i seconds\n" % (datetime.datetime.now(), sleepTime))
time.sleep(sleepTime)
sleepTime *= factor
if sleepTime>maxReconnectTime:
sleepTime=maxReconnectTime
reconnectTry += 1
else:
self.socket=None
if self.verbose:
print "Error indicator: ", error_indicator
if reconnectTry < maxReconnect :
sys.stderr.write( "%s No Connection to NtripCaster. Trying again in %i seconds\n" % (datetime.datetime.now(), sleepTime))
time.sleep(sleepTime)
sleepTime *= factor
if sleepTime>maxReconnectTime:
sleepTime=maxReconnectTime
reconnectTry += 1
except KeyboardInterrupt:
if self.socket:
self.socket.close()
sys.exit()
if __name__ == '__main__':
usage="NtripClient.py [options] [caster] [port] mountpoint"
parser=OptionParser(version=version, usage=usage)
parser.add_option("-u", "--user", type="string", dest="user", default="IBS", help="The Ntripcaster username. Default: %default")
parser.add_option("-p", "--password", type="string", dest="password", default="IBS", help="The Ntripcaster password. Default: %default")
parser.add_option("-o", "--org", type="string", dest="org", help="Use IBSS and the provided organization for the user. Caster and Port are not needed in this case Default: %default")
parser.add_option("-b", "--baseorg", type="string", dest="baseorg", help="The org that the base is in. IBSS Only, assumed to be the user org")
parser.add_option("-t", "--latitude", type="float", dest="lat", default=50.09, help="Your latitude. Default: %default")
parser.add_option("-g", "--longitude", type="float", dest="lon", default=8.66, help="Your longitude. Default: %default")
parser.add_option("-e", "--height", type="float", dest="height", default=1200, help="Your ellipsoid height. Default: %default")
parser.add_option("-v", "--verbose", action="store_true", dest="verbose", default=False, help="Verbose")
parser.add_option("-s", "--ssl", action="store_true", dest="ssl", default=False, help="Use SSL for the connection")
parser.add_option("-H", "--host", action="store_true", dest="host", default=False, help="Include host header, should be on for IBSS")
parser.add_option("-r", "--Reconnect", type="int", dest="maxReconnect", default=1, help="Number of reconnections")
parser.add_option("-D", "--UDP", type="int", dest="UDP", default=None, help="Broadcast recieved data on the provided port")
parser.add_option("-2", "--V2", action="store_true", dest="V2", default=False, help="Make a NTRIP V2 Connection")
parser.add_option("-f", "--outputFile", type="string", dest="outputFile", default=None, help="Write to this file, instead of stdout")
parser.add_option("-m", "--maxtime", type="int", dest="maxConnectTime", default=None, help="Maximum length of the connection, in seconds")
parser.add_option("--Header", action="store_true", dest="headerOutput", default=False, help="Write headers to stderr")
parser.add_option("--HeaderFile", type="string", dest="headerFile", default=None, help="Write headers to this file, instead of stderr.")
(options, args) = parser.parse_args()
ntripArgs = {}
ntripArgs['lat']=options.lat
ntripArgs['lon']=options.lon
ntripArgs['height']=options.height
ntripArgs['host']=options.host
if options.ssl:
import ssl
ntripArgs['ssl']=True
else:
ntripArgs['ssl']=False
if options.org:
if len(args) != 1 :
print "Incorrect number of arguments for IBSS\n"
parser.print_help()
sys.exit(1)
ntripArgs['user']=options.user+"."+options.org + ":" + options.password
if options.baseorg:
ntripArgs['caster']=options.baseorg + ".ibss.trimbleos.com"
else:
ntripArgs['caster']=options.org + ".ibss.trimbleos.com"
if options.ssl :
ntripArgs['port']=52101
else :
ntripArgs['port']=2101
ntripArgs['mountpoint']=args[0]
else:
if len(args) != 3 :
print "Incorrect number of arguments for NTRIP\n"
parser.print_help()
sys.exit(1)
ntripArgs['user']=options.user+":"+options.password
ntripArgs['caster']=args[0]
ntripArgs['port']=int(args[1])
ntripArgs['mountpoint']=args[2]
if ntripArgs['mountpoint'][0:1] !="/":
ntripArgs['mountpoint'] = "/"+ntripArgs['mountpoint']
ntripArgs['V2']=options.V2
ntripArgs['verbose']=options.verbose
ntripArgs['headerOutput']=options.headerOutput
if options.UDP:
ntripArgs['UDP_Port']=int(options.UDP)
maxReconnect=options.maxReconnect
maxConnectTime=options.maxConnectTime
if options.verbose:
print "Server: " + ntripArgs['caster']
print "Port: " + str(ntripArgs['port'])
print "User: " + ntripArgs['user']
print "mountpoint: " +ntripArgs['mountpoint']
print "Reconnects: " + str(maxReconnect)
print "Max Connect Time: " + str (maxConnectTime)
if ntripArgs['V2']:
print "NTRIP: V2"
else:
print "NTRIP: V1 "
if ntripArgs["ssl"]:
print "SSL Connection"
else:
print "Uncrypted Connection"
print ""
fileOutput=False
if options.outputFile:
f = open(options.outputFile, 'w')
ntripArgs['out']=f
fileOutput=True
if options.headerFile:
h = open(options.headerFile, 'w')
ntripArgs['headerFile']=h
ntripArgs['headerOutput']=True
n = NtripClient(**ntripArgs)
try:
n.readData()
finally:
if fileOutput:
f.close()
if options.headerFile:
h.close()Can i do this with B4A?
Can i create a http connection where i can listen to the incoming data like in asyncstream and send new requests (GPGGA String) on the connection to get updates answers linke in the Pythin Script above? How i would do it with B4A?
Any help or suggestions regarding this is highly appreciated.
