QCoapClient#

The QCoapClient class allows the application to send CoAP requests and receive replies. More…

Synopsis#

Functions#

def cancelObserve (url)
def cancelObserve (notifiedReply)
def deleteResource (request)
def deleteResource (url)
def disconnect ()
def discover ([group=QtCoap.MulticastGroup.AllCoapNodesIPv4[, port=QtCoap.DefaultPort[, discoveryPath=QLatin1String(“/.well-known/core”)]]])
def discover (baseUrl[, discoveryPath=QLatin1String(“/.well-known/core”)])
def get (request)
def get (url)
def observe (request)
def observe (request)
def post (request[, data=QByteArray()])
def post (url[, data=QByteArray()])
def post (request, device)
def put (request, device)
def put (request[, data=QByteArray()])
def put (url[, data=QByteArray()])
def setAckRandomFactor (ackRandomFactor)
def setAckTimeout (ackTimeout)
def setBlockSize (blockSize)
def setMaximumRetransmitCount (maximumRetransmitCount)
def setMaximumServerResponseDelay (responseDelay)
def setMinimumTokenSize (tokenSize)
def setSecurityConfiguration (configuration)
def setSocketOption (option, value)

Signals#

def error (reply, error)
def finished (reply)
def responseToMulticastReceived (reply, message, sender)

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description#

The QCoapClient class contains signals that get triggered when the reply of a sent request has arrived.

The application can use a QCoapClient to send requests over a CoAP network. It provides functions for standard requests: each returns a QCoapReply object, to which the response data shall be delivered; this can be read when the finished() signal arrives.

A simple request can be sent with:

QCoapClient *client = new QCoapClient(this);
connect(client, &QCoapClient::finished, this, &TestClass::slotFinished);
client->get(QCoapRequest(Qurl("coap://coap.me/test")));

Note

After processing of the request has finished, it is the responsibility of the user to delete the QCoapReply object at an appropriate time. Do not directly delete it inside the slot connected to finished() . You can use the deleteLater() function.

You can also use an observe request. This can be used as above, or more conveniently with the notified() signal:

QCoapRequest request = QCoapRequest(Qurl("coap://coap.me/obs"));
QCoapReply *reply = client->observe(request);
connect(reply, &QCoapReply::notified, this, &TestClass::slotNotified);

And the observation can be cancelled with:

client->cancelObserve(reply);

When a reply arrives, the QCoapClient emits a finished() signal.

Note

For a discovery request, the returned object is a QCoapResourceDiscoveryReply . It can be used the same way as a QCoapReply but contains also a list of resources.

class PySide6.QtCoap.QCoapClient([securityMode=QtCoap.SecurityMode.NoSecurity[, parent=None]])#

Parameters:

securityMode – SecurityMode
parent – PySide6.QtCore.QObject

Constructs a QCoapClient object for the given securityMode and sets parent as the parent object.

The default for securityMode is NoSecurity , which disables security.

This connects using a QCoapQUdpConnection; to use a custom transport, sub-class QCoapConnection and pass an instance to one of the other constructors.

PySide6.QtCoap.QCoapClient.cancelObserve(url)#

Parameters:: url – PySide6.QtCore.QUrl

This is an overloaded function.

Cancels the observation of a resource identified by the url.

See also

observe()

PySide6.QtCoap.QCoapClient.cancelObserve(notifiedReply)

Parameters:: notifiedReply – PySide6.QtCoap.QCoapReply

This is an overloaded function.

Cancels the observation of a resource using the reply notifiedReply returned by the observe() method.

See also

observe()

PySide6.QtCoap.QCoapClient.deleteResource(request)#

Parameters:: request – PySide6.QtCoap.QCoapRequest
Return type:: PySide6.QtCoap.QCoapReply

Sends the request using the DELETE method and returns a new QCoapReply object.

See also

get() put() post() observe() discover()

PySide6.QtCoap.QCoapClient.deleteResource(url)

Parameters:: url – PySide6.QtCore.QUrl
Return type:: PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends a DELETE request to the target url.

See also

get() put() post() observe() discover()

PySide6.QtCoap.QCoapClient.disconnect()#

Closes the open sockets and connections to free the transport.

Note

In the secure mode this needs to be called before changing the security configuration or connecting to another server.

See also

setSecurityConfiguration()

PySide6.QtCoap.QCoapClient.discover([group=QtCoap.MulticastGroup.AllCoapNodesIPv4[, port=QtCoap.DefaultPort[, discoveryPath=QLatin1String("/.well-known/core")]]])#

Parameters:

group – MulticastGroup
port – int
discoveryPath – str

Return type:

PySide6.QtCoap.QCoapResourceDiscoveryReply

This is an overloaded function.

Discovers the resources available at the endpoints which have joined the group at the given port. Returns a new QCoapResourceDiscoveryReply object which emits the discovered() signal whenever a response arrives. The group is one of the CoAP multicast group addresses and defaults to AllCoapNodesIPv4 .

Discovery path defaults to “/.well-known/core”, but can be changed by passing a different path to discoveryPath. Discovery is described in RFC 6690 .

See also

get() post() put() deleteResource() observe()

PySide6.QtCoap.QCoapClient.discover(baseUrl[, discoveryPath=QLatin1String("/.well-known/core")])

Parameters:

baseUrl – PySide6.QtCore.QUrl
discoveryPath – str

Return type:

PySide6.QtCoap.QCoapResourceDiscoveryReply

Discovers the resources available at the given url and returns a new QCoapResourceDiscoveryReply object which emits the discovered() signal whenever the response arrives.

Discovery path defaults to “/.well-known/core”, but can be changed by passing a different path to discoveryPath. Discovery is described in RFC 6690 .

See also

get() post() put() deleteResource() observe()

PySide6.QtCoap.QCoapClient.error(reply, error)#

Parameters:

reply – PySide6.QtCoap.QCoapReply
error – Error

This signal is emitted whenever an error occurs. The reply parameter can be None if the error is not related to a specific QCoapReply . The error parameter contains the error code.

See also

finished() error() finished()

PySide6.QtCoap.QCoapClient.finished(reply)#

Parameters:: reply – PySide6.QtCoap.QCoapReply

This signal is emitted along with the finished() signal whenever a CoAP reply is received, after either a success or an error. The reply parameter will contain a pointer to the reply that has just been received.

See also

error() finished() error()

PySide6.QtCoap.QCoapClient.get(request)#

Parameters:: request – PySide6.QtCoap.QCoapRequest
Return type:: PySide6.QtCoap.QCoapReply

Sends the request using the GET method and returns a new QCoapReply object.

See also

post() put() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.get(url)

Parameters:: url – PySide6.QtCore.QUrl
Return type:: PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends a GET request to url and returns a new QCoapReply object.

See also

post() put() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.observe(request)#

Parameters:: request – PySide6.QtCoap.QCoapRequest
Return type:: PySide6.QtCoap.QCoapReply

Sends a request to observe the target request and returns a new QCoapReply object which emits the notified() signal whenever a new notification arrives.

See also

cancelObserve() get() post() put() deleteResource() discover()

PySide6.QtCoap.QCoapClient.observe(request)

Parameters:: request – PySide6.QtCore.QUrl
Return type:: PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends a request to observe the target url and returns a new QCoapReply object which emits the notified() signal whenever a new notification arrives.

See also

cancelObserve() get() post() put() deleteResource() discover()

PySide6.QtCoap.QCoapClient.post(request[, data=QByteArray()])#

Parameters:

request – PySide6.QtCoap.QCoapRequest
data – PySide6.QtCore.QByteArray

Return type:

PySide6.QtCoap.QCoapReply

Sends the request using the POST method and returns a new QCoapReply object. Uses data as the payload for this request. If data is empty, the payload of the request will be used.

See also

get() put() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.post(url[, data=QByteArray()])

Parameters:

url – PySide6.QtCore.QUrl
data – PySide6.QtCore.QByteArray

Return type:

PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends a POST request to url and returns a new QCoapReply object. Uses data as the payload for this request.

See also

get() put() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.post(request, device)

Parameters:

request – PySide6.QtCoap.QCoapRequest
device – PySide6.QtCore.QIODevice

Return type:

PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends the request using the POST method and returns a new QCoapReply object. Uses device content as the payload for this request. A null device is treated as empty content.

Note

The device has to be open and readable before calling this function.

PySide6.QtCoap.QCoapClient.put(request, device)#

Parameters:

request – PySide6.QtCoap.QCoapRequest
device – PySide6.QtCore.QIODevice

Return type:

PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends the request using the PUT method and returns a new QCoapReply object. Uses device content as the payload for this request. A null device is treated as empty content.

Note

The device has to be open and readable before calling this function.

PySide6.QtCoap.QCoapClient.put(request[, data=QByteArray()])

Parameters:

request – PySide6.QtCoap.QCoapRequest
data – PySide6.QtCore.QByteArray

Return type:

PySide6.QtCoap.QCoapReply

Sends the request using the PUT method and returns a new QCoapReply object. Uses data as the payload for this request. If data is empty, the payload of the request will be used.

See also

get() post() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.put(url[, data=QByteArray()])

Parameters:

url – PySide6.QtCore.QUrl
data – PySide6.QtCore.QByteArray

Return type:

PySide6.QtCoap.QCoapReply

This is an overloaded function.

Sends a PUT request to url and returns a new QCoapReply object. Uses data as the payload for this request.

See also

get() post() deleteResource() observe() discover()

PySide6.QtCoap.QCoapClient.responseToMulticastReceived(reply, message, sender)#

Parameters:

reply – PySide6.QtCoap.QCoapReply
message – PySide6.QtCoap.QCoapMessage
sender – PySide6.QtNetwork.QHostAddress

This signal is emitted when a unicast response to a multicast request arrives. The reply parameter contains a pointer to the reply that has just been received, message contains the payload and the message details, and sender contains the sender address.

See also

error() finished() error()

PySide6.QtCoap.QCoapClient.setAckRandomFactor(ackRandomFactor)#

Parameters:: ackRandomFactor – double

Sets the ACK_RANDOM_FACTOR value defined in RFC 7252 - Section 4.2 , to ackRandomFactor. This value should be greater than or equal to 1. The default is 1.5.

See also

setAckTimeout()

PySide6.QtCoap.QCoapClient.setAckTimeout(ackTimeout)#

Parameters:: ackTimeout – uint

Sets the ACK_TIMEOUT value defined in RFC 7252 - Section 4.2 to ackTimeout in milliseconds. The default is 2000 ms.

This timeout only applies to confirmable messages. The actual timeout for reliable transmissions is a random value between ACK_TIMEOUT and ACK_TIMEOUT * ACK_RANDOM_FACTOR.

See also

setAckRandomFactor()

PySide6.QtCoap.QCoapClient.setBlockSize(blockSize)#

Parameters:: blockSize – quint16

Sets the maximum block size used by the protocol to blockSize when sending requests and receiving replies. The block size must be a power of two.

PySide6.QtCoap.QCoapClient.setMaximumRetransmitCount(maximumRetransmitCount)#

Parameters:: maximumRetransmitCount – uint

Sets the MAX_RETRANSMIT value defined in RFC 7252 - Section 4.2 to maximumRetransmitCount. This value should be less than or equal to 25. The default is 4.

PySide6.QtCoap.QCoapClient.setMaximumServerResponseDelay(responseDelay)#

Parameters:: responseDelay – uint

Sets the MAX_SERVER_RESPONSE_DELAY value to responseDelay in milliseconds. The default is 250 seconds.

As defined in RFC 7390 - Section 2.5 , MAX_SERVER_RESPONSE_DELAY is the expected maximum response delay over all servers that the client can send a multicast request to.

PySide6.QtCoap.QCoapClient.setMinimumTokenSize(tokenSize)#

Parameters:: tokenSize – int

Sets the minimum token size to tokenSize in bytes. For security reasons it is recommended to use tokens with a length of at least 4 bytes. The default value for this parameter is 4 bytes.

PySide6.QtCoap.QCoapClient.setSecurityConfiguration(configuration)#

Parameters:: configuration – PySide6.QtCoap.QCoapSecurityConfiguration

Sets the security configuration parameters from configuration. Configuration will be ignored if the NoSecurity mode is used.

Note

This method must be called before the handshake starts. If you need to change the security configuration after establishing a secure connection with the server, the client needs to be disconnected first.

See also

disconnect()

PySide6.QtCoap.QCoapClient.setSocketOption(option, value)#

Parameters:

option – SocketOption
value – object

Sets the QUdpSocket socket option to value.