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Send variable from LabVIEW 2016 to Rasperry Pi 3 via TCP/IP to incorperate in code

I am trying to create a few inputs in LabVIEW 2016 which a user can modify (eg. total frames = 100). This number will then be sent to and RPi3 unit which is running a basic TCP/IP server script. The idea is that these numbers will set the variables in a simple instrument control code. I can connect to the RPi in LabVIEW and can send a string but things break down there:
-the string seems to be sent as Decimal ASCII
-when decoded in python, the string is converted so that every character is a separate element, with a separate index (eg. if I send 100 I get str[0]=1, str[1]=0, str[2]=0, len(str)=3)
-i need to send several variables and several commands in one string and then unpack it in python so that I can call each one separately and assign it to the appropriate function
Any advice would be appreciated.

I would personally just create a cluster of your paramters in labview, then use 'flatten to json' and you can simply decode that in python into a object with each of your variables inside it.
in python, you can then easily load that config data
import json
# sample string, replace this with received data from client/server comms
config = '{'total frames': 100, 'rate': 30, 'additional': 'whatever'}'
newconfig = json.loads(config)
print( list(newconfig) ) # list of all the tuples
# ['total frames', 'rate', 'additional']
# to access any tuple
num_frames = newconfig['total frames']

Working with TCP sockets in Python

I need to:
1) Create a socket to a specific IP and Port
2) Send a string of data via the connection
3) Await the response and check it is valid
I have seen a lot of conflicting advice at the moment and so decided to ask a new question to try and clear this up.
I'm trying to use the socket library in Python to achieve this however am facing a couple of issues. I've tried a few different methods, however I am facing an issue sending the string of data. My data is in XML format so getting this as a string is proving difficult for me. I have attempted converting it to binary however would prefer it in plain text format, just that it should be as a string. Any pointers as to whether the code would fulfil the 3 steps I wish to complete would be perfect!
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('109.73.xxx.xxx', 29006))
s.sendall('*XML SHOULD GO HERE*')
data = s.recv(1024)
s.close()
print 'Received', repr(data)
I haven't got a response back from the server at the moment because I suspect of the erroneous format of the string of data sent. This means I haven't been able to check whether the code prints the response data from the server.
The XML data I need to pass as a string is in the following format:
<Message xmlns:xsi="http://www.w3.org/CANNOTPROVIDETHISURL" xmlns:xsd="http://www.w3.org/CANNOTPROVIDETHISURL">
<ClientHeader>
<element1>RC1234</element1>
<element2>1234</element2>
<element3>12345678</element3>
<element4>123456789</element4>
<element5>-1</element5>
<element6>-1</element6>
<element7>A123</element7>
<element8>TMS</element8>
</ClientHeader>
<MsgType>TYPE</MsgType>
<MsgData></MsgData>
</Message>

How to separate values received from a serial port and store it as separate variables in python?

I am new to python, to sensors and Stackoverflow. I am working on a project at my uni to read 4 sensor data on COM4 of my pc through pyserial. I wrote the below code to accomplish this:
import serial
ser = serial.Serial('COM4', 9600, timeout=5)
ser.write("\r".encode())
response = ser.read(60)
print (response)
ser.close()
I get the output something like:
b'reply:node01\r\n69\r\n45\r\n117\r\n994\r\n
Values 69,45,117,994 are readings from the 4 sensors respectively. I did some research and changed print (response) to print (response.decode('utf-8')) , now I get the output which looks like:
reply:node01
69
45
117
994
I really need some help in separating and storing the sensor values from my initial output or from the output that I received after adding print (response.decode('utf-8')) as separate variables, something like field1=69, field2=45, field3=117, field4=994. So that I can send this to thingspeak API:
https://api.thingspeak.com/update?api_key=XXXXXXXXXXXXXXXXXXX&field1=69&field=45&field3=117&field4=994
PS: Scalable - more number of sensors might be added at later stage of this project, so the number of data values received will also increase.
Please, I really need some help with this.

Good call on the conversion to text from bytes. Now suppose you store that decoded string, as in
my_str = response.decode('utf-8')
You can use the splitlines string method to get strings for each line:
field0, field1, field2, field3, field4 = my_str.splitlines()
Then you can interpolate those values into some template to give you the URL you want. If you'd prefer a list of the values, just use
fields = my_str.splitlines()

Convert received data in C++

I'm Working with Arduino (C++) and Raspberry Pi (Pyhon) with a RF module.
I've some doubts with the conversion of the data. I'm sending this data from Arduino:
unsigned long numbers = {12345678};
and Raspberry receive: 12345678
The library I'm using has a ackPayload function, so I can send data back like this:
akpl_buf = [c,1,2,3]
The c variable is just an incremental number.
Now, in the Arduino I receive this:
Received Ack:235802126
I use an static uint32_t variable to receive the answer to the raspberry and I printed it like this (In Arduino C++): printf("Received Ack:%lu\n\r",message_count);
The question is, how can I convert the received data? it should be like: 12,1,2,3 or 12123
Plus: what type of data is currently printing?

After some research and ask some people, I knew that the RF library returned the data in bytes so Received Ack:235802126 is the conversion from byte to unsigned long
so what I had to do was assign that data to a char array, and after that print it
char data[20];
importData(&data);
data[size+1] = '\0';
print data;
something like that.

python concatenate ctype struct and array

I am trying to implement a custom UDP protocol. This protocol has a header and data. The header has information about the structure of the data.
The header is defined using a ctypes struct and the data using 'h' array(signed short).
I am using python sockets.
I tried sending the header ans data using separate calls to "socket.sendto" like this:
s.sendto(header, addr)
s.sendto(data, addr)
But I am not able to receive this as a continuous stream. "socket.recvfrom" is only fetching the header. Maybe if I call "socket.recvfrom" again I will get the data as well. But thats not what I need. I need the full packet as a stream. I think concatenating the header and data in the server itself might fix this.
So I tried different combinations of the following to concatenate the two:
converting the header to "c_char_p" array.
Converting the data to bytearray
using numpy.concatenate
Standard array concatenation after converting the header to 'B' array.
Converting header to 'h' array. (This failed with "string length not a multiple of item size"
All the above failed for one reason or the other.
If I need to convert either header or data, I would prefer it to be the header as it is smaller. But if there is no way around, I am ok with converting the data.
Would appreciate any help.
Relevant code snippets:
sdata = array("h")
.
.
.
header=protocol.HEADER(1,50,1,50,1,50,1,50,1,10,1,12,1,1,1,1,1,18,19,10,35,60,85,24,25)
.
.
s.sendto(header+sdata, addr)

You can copy the header struct into a ctypes array of bytes:
>>> buf = (ctypes.c_char * ctypes.sizeof(header)).from_buffer_copy(header)
Now, in Python 2,
>>> buf.raw + sdata.tostring()
should give you what you're looking for.
In Python 3, it would be
>>> buf.raw + sdata.tobytes()