[microWebSrv2] ValueError: can't perform relative import

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ExDes
Posts: 3
Joined: Thu Apr 29, 2021 10:25 pm

[microWebSrv2] ValueError: can't perform relative import

Post by ExDes » Sun May 09, 2021 4:46 pm

Hello fellow micropythoners,
I am attempting to incorporate the current microWebSrv2 module into the latest micropython build. We are using the NUCLEO-F767ZI board. Threading has been enabled in /ports/stm32/mpconfigport.py. Module microWebSrv2 has been frozen into the build by including the following into /ports/stm32/boards/manifest.py:

Code: Select all

freeze("$(MPY_DIR)/ports/stm32/modules/MicroWebSrv2", ("httpRequest.py", "httpResponse.py", "__init__.py", "microWebSrv2.py", "webRoute.py"))
freeze("$(MPY_DIR)/ports/stm32/modules/MicroWebSrv2/libs", ("urlUtils.py", "XAsyncSockets.py"))
freeze("$(MPY_DIR)/ports/stm32/modules/MicroWebSrv2/mods", ("PyhtmlTemplate.py", "WebSockets.py"))
I created a modules directory in the /ports/stm32/ directory and placed the relevant MicroWebSrv2 files and directories into this directory. Please correct me if this is not a proper method of freezing modules.

To test the implementation, I placed the example from the microWebSrv2 repository (https://github.com/jczic/MicroWebSrv2/b ... er/main.py) into the PYBFLASH directory. Code is as follows:

Code: Select all

from microWebSrv2  import *
from time          import sleep
from _thread       import allocate_lock

# ============================================================================
# ============================================================================
# ============================================================================

@WebRoute(GET, '/test-redir')
def RequestTestRedirect(microWebSrv2, request) :
    request.Response.ReturnRedirect('/test.pdf')

# ============================================================================
# ============================================================================
# ============================================================================

@WebRoute(GET, '/test-post', name='TestPost1/2')
def RequestTestPost(microWebSrv2, request) :
    content = """\
    <!DOCTYPE html>
    <html>
        <head>
            <title>POST 1/2</title>
        </head>
        <body>
            <h2>MicroWebSrv2 - POST 1/2</h2>
            User address: %s<br />
            <form action="/test-post" method="post">
                First name: <input type="text" name="firstname"><br />
                Last name:  <input type="text" name="lastname"><br />
                <input type="submit" value="OK">
            </form>
        </body>
    </html>
    """ % request.UserAddress[0]
    request.Response.ReturnOk(content)

# ------------------------------------------------------------------------

@WebRoute(POST, '/test-post', name='TestPost2/2')
def RequestTestPost(microWebSrv2, request) :
    data = request.GetPostedURLEncodedForm()
    try :
        firstname = data['firstname']
        lastname  = data['lastname']
    except :
        request.Response.ReturnBadRequest()
        return
    content   = """\
    <!DOCTYPE html>
    <html>
        <head>
            <title>POST 2/2</title>
        </head>
        <body>
            <h2>MicroWebSrv2 - POST 2/2</h2>
            Hello %s %s :)<br />
        </body>
    </html>
    """ % ( MicroWebSrv2.HTMLEscape(firstname),
            MicroWebSrv2.HTMLEscape(lastname) )
    request.Response.ReturnOk(content)

# ============================================================================
# ============================================================================
# ============================================================================

def OnWebSocketAccepted(microWebSrv2, webSocket) :
    print('Example WebSocket accepted:')
    print('   - User   : %s:%s' % webSocket.Request.UserAddress)
    print('   - Path   : %s'    % webSocket.Request.Path)
    print('   - Origin : %s'    % webSocket.Request.Origin)
    if webSocket.Request.Path.lower() == '/wschat' :
        WSJoinChat(webSocket)
    else :
        webSocket.OnTextMessage   = OnWebSocketTextMsg
        webSocket.OnBinaryMessage = OnWebSocketBinaryMsg
        webSocket.OnClosed        = OnWebSocketClosed

# ============================================================================
# ============================================================================
# ============================================================================

def OnWebSocketTextMsg(webSocket, msg) :
    print('WebSocket text message: %s' % msg)
    webSocket.SendTextMessage('Received "%s"' % msg)

# ------------------------------------------------------------------------

def OnWebSocketBinaryMsg(webSocket, msg) :
    print('WebSocket binary message: %s' % msg)

# ------------------------------------------------------------------------

def OnWebSocketClosed(webSocket) :
    print('WebSocket %s:%s closed' % webSocket.Request.UserAddress)

# ============================================================================
# ============================================================================
# ============================================================================

global _chatWebSockets
_chatWebSockets = [ ]

global _chatLock
_chatLock = allocate_lock()

# ------------------------------------------------------------------------

def WSJoinChat(webSocket) :
    webSocket.OnTextMessage = OnWSChatTextMsg
    webSocket.OnClosed      = OnWSChatClosed
    addr = webSocket.Request.UserAddress
    with _chatLock :
        for ws in _chatWebSockets :
            ws.SendTextMessage('<%s:%s HAS JOINED THE CHAT>' % addr)
        _chatWebSockets.append(webSocket)
        webSocket.SendTextMessage('<WELCOME %s:%s>' % addr)

# ------------------------------------------------------------------------

def OnWSChatTextMsg(webSocket, msg) :
    addr = webSocket.Request.UserAddress
    with _chatLock :
        for ws in _chatWebSockets :
            ws.SendTextMessage('<%s:%s> %s' % (addr[0], addr[1], msg))

# ------------------------------------------------------------------------

def OnWSChatClosed(webSocket) :
    addr = webSocket.Request.UserAddress
    with _chatLock :
        if webSocket in _chatWebSockets :
            _chatWebSockets.remove(webSocket)
            for ws in _chatWebSockets :
                ws.SendTextMessage('<%s:%s HAS LEFT THE CHAT>' % addr)

# ============================================================================
# ============================================================================
# ============================================================================

print()

# Loads the PyhtmlTemplate module globally and configure it,
pyhtmlMod = MicroWebSrv2.LoadModule('PyhtmlTemplate')
pyhtmlMod.ShowDebug = True
pyhtmlMod.SetGlobalVar('TestVar', 12345)

# Loads the WebSockets module globally and configure it,
wsMod = MicroWebSrv2.LoadModule('WebSockets')
wsMod.OnWebSocketAccepted = OnWebSocketAccepted

# Instanciates the MicroWebSrv2 class,
mws2 = MicroWebSrv2()

# SSL is not correctly supported on MicroPython.
# But you can uncomment the following for standard Python.
# mws2.EnableSSL( certFile = 'SSL-Cert/openhc2.crt',
#                 keyFile  = 'SSL-Cert/openhc2.key' )

# For embedded MicroPython, use a very light configuration,
mws2.SetEmbeddedConfig()

# All pages not found will be redirected to the home '/',
mws2.NotFoundURL = '/'

# Starts the server as easily as possible in managed mode,
mws2.StartManaged()

# Main program loop until keyboard interrupt,
try :
    while mws2.IsRunning :
        sleep(1)
except KeyboardInterrupt :
    pass

# End,
print()
mws2.Stop()
print('Bye')
print()

# ============================================================================
# ============================================================================
# ============================================================================
Upon resetting the processor board, it produces this output:

Traceback (most recent call last):
File "main.py", line 1, in <module>
File "microWebSrv2.py", line 10, in <module>
ValueError: can't perform relative import
MicroPython v1.15-37-gd3eb6d68a-dirty on 2021-05-09; NUCLEO-F767ZI with STM32F767
Type "help()" for more information.
>>>


Software built in a standard PC running Linux Mint 19.3 Cinnamon, if this is relevant.

Any help would be much appreciated!

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