python_test_tcp_server.py

import network
import utime as time
import usocket as socket
import random

# Set your wifi ssid and password here
WIFI_SSID = const('')
WIFI_PASSWORD = const('')

# These constants should match the client
BUF_SIZE = const(2048)
SERVER_PORT = const(4242)
TEST_ITERATIONS = const(10)

# Check if wifi details have been set
if len(WIFI_SSID) == 0 or len(WIFI_PASSWORD) == 0:
    raise RuntimeError('Please set wifi ssid and password in this script')

# Start connection
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(WIFI_SSID, WIFI_PASSWORD)

# Wait for connect success or failure
max_wait = 20
while max_wait > 0:
    if wlan.status() < 0 or wlan.status() >= 3:
        break
    max_wait -= 1
    print('waiting for connection...')
    time.sleep(1)

# Handle connection error
if wlan.status() != 3:
    raise RuntimeError('wifi connection failed %d' % wlan.status())
else:
    print('connected')
    status = wlan.ifconfig()
    print( 'ip = ' + status[0] )

# Open socket to the server
sock = socket.socket()
addr = ('0.0.0.0', SERVER_PORT)
sock.bind(addr)
sock.listen(1)
print('server listening on', addr)

# Wait for the client
con = None
con, addr = sock.accept()
print('client connected from', addr)

# repeat test for a number of iterations
for test_iteration in range(TEST_ITERATIONS):

    # Generate a buffer of random data
    random_list = []
    for n in range(BUF_SIZE):
        random_list.append(random.randint(0, 255))
    write_buf = bytearray(random_list)

    # write BUF_SIZE bytes to the client
    write_len = con.send(bytearray(write_buf))
    print('Written %d bytes to client' % write_len)

    # Check size of data written
    if write_len != BUF_SIZE:
        raise RuntimeError('wrong amount of data written')

    # Read the data back from the client
    read_buf = con.read(BUF_SIZE)
    print('read %d bytes from client' % len(read_buf))

    # Check size of data received
    if len(read_buf) != BUF_SIZE:
        raise RuntimeError('wrong amount of data read')

    # Check the data sent and received
    if read_buf != write_buf:
        raise RuntimeError('buffer mismatch')

# All done
con.close()
sock.close()
print("test completed")