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Diffstat (limited to 'docs/esp8266/tutorial/network_tcp.rst')
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diff --git a/docs/esp8266/tutorial/network_tcp.rst b/docs/esp8266/tutorial/network_tcp.rst deleted file mode 100644 index 26a2f469c..000000000 --- a/docs/esp8266/tutorial/network_tcp.rst +++ /dev/null @@ -1,122 +0,0 @@ -Network - TCP sockets -===================== - -The building block of most of the internet is the TCP socket. These sockets -provide a reliable stream of bytes between the connected network devices. -This part of the tutorial will show how to use TCP sockets in a few different -cases. - -Star Wars Asciimation ---------------------- - -The simplest thing to do is to download data from the internet. In this case -we will use the Star Wars Asciimation service provided by the blinkenlights.nl -website. It uses the telnet protocol on port 23 to stream data to anyone that -connects. It's very simple to use because it doesn't require you to -authenticate (give a username or password), you can just start downloading data -straight away. - -The first thing to do is make sure we have the socket module available:: - - >>> import socket - -Then get the IP address of the server:: - - >>> addr_info = socket.getaddrinfo("towel.blinkenlights.nl", 23) - -The ``getaddrinfo`` function actually returns a list of addresses, and each -address has more information than we need. We want to get just the first valid -address, and then just the IP address and port of the server. To do this use:: - - >>> addr = addr_info[0][-1] - -If you type ``addr_info`` and ``addr`` at the prompt you will see exactly what -information they hold. - -Using the IP address we can make a socket and connect to the server:: - - >>> s = socket.socket() - >>> s.connect(addr) - -Now that we are connected we can download and display the data:: - - >>> while True: - ... data = s.recv(500) - ... print(str(data, 'utf8'), end='') - ... - -When this loop executes it should start showing the animation (use ctrl-C to -interrupt it). - -You should also be able to run this same code on your PC using normal Python if -you want to try it out there. - -HTTP GET request ----------------- - -The next example shows how to download a webpage. HTTP uses port 80 and you -first need to send a "GET" request before you can download anything. As part -of the request you need to specify the page to retrieve. - -Let's define a function that can download and print a URL:: - - def http_get(url): - _, _, host, path = url.split('/', 3) - addr = socket.getaddrinfo(host, 80)[0][-1] - s = socket.socket() - s.connect(addr) - s.send(bytes('GET /%s HTTP/1.0\r\nHost: %s\r\n\r\n' % (path, host), 'utf8')) - while True: - data = s.recv(100) - if data: - print(str(data, 'utf8'), end='') - else: - break - s.close() - -Make sure that you import the socket module before running this function. Then -you can try:: - - >>> http_get('http://micropython.org/ks/test.html') - -This should retrieve the webpage and print the HTML to the console. - -Simple HTTP server ------------------- - -The following code creates an simple HTTP server which serves a single webpage -that contains a table with the state of all the GPIO pins:: - - import machine - pins = [machine.Pin(i, machine.Pin.IN) for i in (0, 2, 4, 5, 12, 13, 14, 15)] - - html = """<!DOCTYPE html> - <html> - <head> <title>ESP8266 Pins</title> </head> - <body> <h1>ESP8266 Pins</h1> - <table border="1"> <tr><th>Pin</th><th>Value</th></tr> %s </table> - </body> - </html> - """ - - import socket - addr = socket.getaddrinfo('0.0.0.0', 80)[0][-1] - - s = socket.socket() - s.bind(addr) - s.listen(1) - - print('listening on', addr) - - while True: - cl, addr = s.accept() - print('client connected from', addr) - cl_file = cl.makefile('rwb', 0) - while True: - line = cl_file.readline() - if not line or line == b'\r\n': - break - rows = ['<tr><td>%s</td><td>%d</td></tr>' % (str(p), p.value()) for p in pins] - response = html % '\n'.join(rows) - cl.send(response) - cl.close() |