I'm working with a tiny micro-webserver running on my pyboard 'D'. The link explains how to get the code up and running on the pyboard 'D'.
I've noticed that for large files (for me an png image of 71k) that sometimes the whole image will not be returned. The board seems to hang slightly, then the connection is broken. My image file that I used for testing is here
To investigate further I hit the web server with curl requests. Waiting first till the file was served before hitting the device with another curl request. My curl requests look like:
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nherriot@Zenbook-UX32A ~ $ curl -X GET http://192.168.110.143:8000/thumb.png > thumb.png
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 71268 100 71268 0 0 205k 0 --:--:-- --:--:-- --:--:-- 205k
nherriot@Zenbook-UX32A ~ $ curl -X GET http://192.168.110.143:8000/thumb.png > thumb.png
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 71268 100 71268 0 0 220k 0 --:--:-- --:--:-- --:--:-- 220k
nherriot@Zenbook-UX32A ~ $ curl -X GET http://192.168.110.143:8000/thumb.png > thumb.png
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
10 71268 10 7403 0 0 2199 0 0:00:32 0:00:03 0:00:29 2199
[color=#BF0000]curl: (18) transfer closed with 63865 bytes remaining to read[/color]
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Connected on IP: 192.168.110.143
Accepted 'client': <socket state=3 timeout=-1 incoming=0 off=0> and 'client address': ('192.168.110.147', 42094)
Processing request HTTP Method: GET Path: /thumb.png Version: HTTP/1.1
Server writing file: www//thumb.png of size: 71268 of type: image/png to host: ('192.168.110.147', 42094)
Last: 612 octets being sent
Accepted 'client': <socket state=3 timeout=-1 incoming=0 off=0> and 'client address': ('192.168.110.147', 42152)
Processing request HTTP Method: GET Path: /thumb.png Version: HTTP/1.1
Server writing file: www//thumb.png of size: 71268 of type: image/png to host: ('192.168.110.147', 42152)
Last: 612 octets being sent
Connected on IP: 192.168.110.143
Accepted 'client': <socket state=3 timeout=-1 incoming=0 off=0> and 'client address': ('192.168.110.147', 42178)
Processing request HTTP Method: GET Path: /thumb.png Version: HTTP/1.1
Server writing file: www//thumb.png of size: 71268 of type: image/png to host: ('192.168.110.147', 42178)
The code that deals with sending the file over a socket looks like:Last: 612 octets being sent
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def WriteResponseFile(self, filepath, contentType=None, headers=None):
"""
A method to write a file to the client. It takes the path of the file, calculates it's size and copies the file in chunk
sizes of 1024 octets via the low level socket interface. The method first builds the first line of the HTTP request and
provides headers, content type, reason code and size of the file. It then does the sending of the file in 1024 octet chunks
to the client.
If there is a failure in reading the file a WriteREsponseNotFound is sent.
If there is a faulure in sending the file to the client a WriteResponseInternalServerError is sent.
:param filepath: (e.g. www/style.css)
:param contentType: (e.g. text/html)
:param headers: (e.g. {'Cache-Control': 'max-age=315360000', 'Last-Modified': 'Fri, 1 Jan 2018 23:42:00 GMT'})
:return: Boolean
"""
try :
size = stat(filepath)[6]
print("Server writing file: {} of size: {} of type: {} to host: {}".format(filepath, size, contentType, self._client._addr ))
if size > 0 :
with open(filepath, 'rb') as file : # Open file for reading in binary mode
self._writeBeforeContent(200, headers, contentType, None, size) # Write our HTTP header
try :
buf = bytearray(1024)
while size > 0 :
x = file.readinto(buf)
if x < len(buf) :
buf = memoryview(buf)[:x]
print("Last: {} octets being sent".format(x))
self._write(buf) # call up low level socket write function
size -= x
return True
except :
self.WriteResponseInternalServerError()
return False
except :
pass
self.WriteResponseNotFound()
return False
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def _write(self, data):
if data :
if type(data) == str :
data = data.encode()
return self._client._socketfile.write(data)
return 0
Things to note. The microWebSrv is using a single thread to handle all requests that come in to the web server. What i don't understand is:
1) Why the except is not called when it fails?
2) Why it mostly works, but sometimes not?
The micropython build I'm using is:
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repl
Entering REPL. Use Control-X to exit.
>
MicroPython v1.11-63-gd889def-dirty on 2019-07-02; PYBD-SF2W with STM32F722IEK
Type "help()" for more information.
If someone could let me know what other things can i do in terms of debugging? How can I see what is going on in the embedded device to somehow totally stop running this piece of code????
I've run the same code directly on my PC with python 3.6 and none of the issues exist, so it seems to be unique to the board. Furthermore nobody on the micrWebSrv github repo seem to report or notice this when testing on the ESP Boards, so maybe this only on the new pyboard 'D' that it happens?
Any help is gratefully appreciated.
Kind regards, Nicholas.
