I am looking to retrieve some Solace queue stats e.g. the current messages spooled count out of the maximum limit for us to set a threshold to stop publishing more messages to the queue.
Also, to subscribe to vpn events to track message discard rates.
By the time we receive errors e.g. MaxMsgUsageExceeded/SpoolOverQuota, it will be too late.
I can't seem to find any of these on SolaceSystems.Solclient.Messaging API
https://docs.solace.com/API-Developer-Online-Ref-Documentation/net/html/7f10bcf6-19f4-beff-0768-ced843e35168.htm
Would be great if someone could help
(using C# for this)
To poll for Solace queue stats from your C# application, you could use legacy SEMP over the message bus to make a SEMP request for the details that you want. Semp (Solace Element Management Protocol) is a request/reply protocol that uses an XML schema to identify all managed objects available in a message broker. Applications can use SEMP to manage and monitor a message broker.
To allow for legacy SEMP to be used over the message bus, as opposed to the management interface, it first needs to be enabled on the Solace PubSub+ message broker at the VPN level.
To publish a SEMP request with the Solace .Net Messaging API, perform the following steps:
Create a Session.
Create the message topic. “#SEMP//SHOW”
ITopic topic = ContextFactory.Instance.CreateTopic( “#SEMP/<router name>/SHOW”);
Create a request message and set its Destination to the topic in Step 2:
IMessage requestMsg = ContextFactory.Instance.CreateMessage();
requestMsg.Destination = topic;
Set the SEMP request string as the binary attachment.
string SOLTR_VERSION = "8_4_0" //change to the message-broker's version
string SEMP_SHOW_QUEUE = "<rpc semp-version=\"soltr/" + SOLTR_VERSION +
"<show><queue><name>queueName</name><detail></detail></queue></show></rpc>";
requestMsg.BinaryAttachment = Encoding.UTF8.GetBytes(SEMP_SHOW_QUEUE);
Call the SendRequest(…) method on Session.
IMessage replyMsg;
ReturnCode rc = session.SendRequest(requestMsg, out replyMsg, timeout);
The SEMP response is returned in replyMsg.
Obtain the binary attachment data from the reply message:
replyMsg.BinaryAttachment
The binary attachment contains the SEMP reply for the command topic in the publish request.
The Solace PubSub+ message broker does raise an event when an egress message is discarded. However, it is only sent out approximately once every 60 seconds for the specified client so it is not possible to get these exact rates.
It is possible for your .NET application to subscribe to VPN-level events over the message-bus. To do this, you must first enable the Solace PubSub+ message broker to publish the events. You can then subscribe to the special topic and receive the events as messages.
The topic to subscribe to is:
#LOG/<level>/VPN/<routerName>/<eventName>/<vpnName>
The different levels can use the * wildcard. For example, if you wish to subscribe to all VPN events of all levels for the VPN apple on router QA-NY1, the topic string would be:
#LOG/*/VPN/QA-NY1/*/apple
SEMP (starting in v2) is a RESTful API for configuring, monitoring, and administering a Solace PubSub+ broker.
1-The swapper page link is SEMP V2 API
2-The Swagger metadata definitions URL is located # http://{solace-sever-url}/SEMP/v2/config/spec
3- From Visual studio, add REST API Client
4-In the configuration dialog pass swagger metadata URL (defined at step 2), for code purpose I choose SolaceSemp as input value parameter for client namespace input.
4 Once you click ok, VS will create the client along with the models under SolaceSemp namespace
5 Start using the client as per following
using SolaceSemp;
using Microsoft.Rest;
var credentials = new BasicAuthenticationCredentials();
credentials.UserName = "place user name";
credentials.Password = "place password";
using (var client = new SolaceSempClient(credentials))
{
var model = client.GetAboutApi();
}
Related
I borrowed code from Toms Hardware on how to use MQTT and subscribe. JRMI is the publisher of the messages and it keeps repeating them over and over again. Is there anyway to have the message sent only once? I dont have this problem when I subscribe to MQTT via http://www.hivemq.com/demos/websocket-client/ The MQTT service I'm using is broker.hivemq.com
For those not familiar with JRMI, it is the JAVA program that model railroads use to control tracks,lighting, DCC etc. Ref: https://www.jmri.org/
The link to Tom's is here https://www.tomshardware.com/how-to/send-and-receive-data-raspberry-pi-pico-w-mqtt
The code adapted from Tom's is
import network
import time
from machine import Pin
from umqtt.simple import MQTTClient
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect("whatever","pwd")
time.sleep(5)
print(wlan.isconnected())
mqtt_server = 'broker.hivemq.com'
client_id = 'bigles'
topic_sub = b'/trains/track/turnout/#'
def sub_cb(topic, msg):
print("New message on topic {}".format(topic.decode('utf-8')))
msg = msg.decode('utf-8')
print(msg)
def mqtt_connect():
client = MQTTClient(client_id, mqtt_server, keepalive=60)
client.set_callback(sub_cb)
client.connect()
print('Connected to %s MQTT Broker'%(mqtt_server))
return client
def reconnect():
print('Failed to connect to MQTT Broker. Reconnecting...')
time.sleep(5)
machine.reset()
try:
client = mqtt_connect()
except OSError as e:
reconnect()
while True:
client.subscribe(topic_sub)
time.sleep(1)
The setup inside JRMI for MQTT (edit->preferences) is as follows:
JMRI, by default, publishes with "the retain option on". When you subscribe to a topic the broker will send you the most recent (if any) retained message. This occurs even if you already had an identical subscription as per the MQTT Spec:
If a Server receives a SUBSCRIBE Packet containing a Topic Filter that is identical to an existing Subscription’s Topic Filter then it MUST completely replace that existing Subscription with a new Subscription. The Topic Filter in the new Subscription will be identical to that in the previous Subscription, although its maximum QoS value could be different. Any existing retained messages matching the Topic Filter MUST be re-sent, but the flow of publications MUST NOT be interrupted [MQTT-3.8.4-3].
In your code you are calling Subscribe in a loop:
while True:
client.subscribe(topic_sub)
time.sleep(1)
To avoid the repeated messages move the subscribe out of the loop (you only need to subscribe once!). Something like the following (simplified!) code:
client = mqtt_connect()
client.subscribe(topic_sub)
while True:
client.wait_msg() // Use client.check_msg() if you have other stuff to do
I am creating a Flow instance for a ITopicEndpoint, the documentation says that ISubscription should be passed to the createFlow method only if endpoint is of type ISubscriberEndpoint.
From the documentation
subscription Type:
SolaceSystems.Solclient.Messaging.ISubscription Only valid if endpoint
is of type ISubscriberEndpoint.
I am creating a Flow for a ITopicEndpoint so why am I getting the below error. What should i pass for ISubscription?
System.ArgumentException: 'subscription must be non-null when endpoint is of type ITopicEndpoint'
topic = ContextFactory.Instance.CreateDurableTopicEndpointEx(topicName);
flow = session.CreateFlow(flowProps, topic, null, HandleFlowMessageEvent, HandleFlowEvent);
For a durable topic endpoint, if you have multiple subscribers then each would have to register with a unique subscription name so that the broker can maintain a durable connection with the specific subscriber. Even if the subscriber is down for a while and reconnects, it will not loose out on messages in the interim. The broker will push the messages to the subscriber.
You can create a subscriber via the Solace Admin client or via code.
Solace Admin -> Select the VPN -> Choose Endpoint tab -> select Durable Topic Endpoint -> click the + sign to create a subscriber -> ensure that consume is chosen for 'All other Permissions'
I have published a message in the solace interface and got the messageId generated for that.
From SolAdmin, When I inspect the queue, I can able to see one new messages received, but the message id which generated is not same.
TextMessage txtMsg = jmsSession.createTextMessage();
messageID = txtMsg.getJMSMessageID();
The above messageID generated the output as
ID:2eaaf46d-b9ff-4aeb-a385-fbc2e6cced0a:1:1:1-1
But in SolAdmin, the message shows as 5985824677
The "Message ID" that is shown in the endpoints tab of SolAdmin is internal to the Solace Message Broker and is not equivalent to the "JMS Message ID".
You can use it for operations such as deleting some messages via the CLI or SEMP.
For example:
solace(admin/message-spool)# delete-messages queue my_sample_queue message 123456789 to 123456790
There's no way to display the JMS Message ID in SolAdmin.
Instead, you will need to make use of a queue browser to browse messages in the queue.
This can be a custom application that you write, sdkperf (use the -qb and -md flags), or a third party graphical JMS queue browser such as HermesJMS.
I am using c# M2MQTT Client code to publish and subscribe the data. I have set the QOS Level 1 or 2. Do not know that how the publisher will get the notification when delivery completes. I have searched a lot on inter net but no code available. Please let me know if any one how to handle the acknowledgement at publisher end in c#.
MqttClient client = new MqttClient(IPAddress.Parse(mqttserverurl));
clientId = Guid.NewGuid().ToString();
client.Connect(clientId, uname, pwd);`enter code here`
client.Publish("testtopic", Encoding.UTF8.GetBytes("Hi"), MqttMsgBase.QOS_LEVEL_EXACTLY_ONCE, false);
You don't.
It's all handled internally by the MQTT client library and M2MQTT doesn't seem to have a on_publish callback.
Using the twilio-ruby package to connect to the REST API for Twilio's IP Messaging service and attempting to compute an unread message count.
The REST API is paginating the messages so that something like
channel.messages.list.last.index
Will return 49 once there are more than 50 messages in the channel.
Is there a way to get just the last message on the channel (as seems to be possible in the android/ios SDK) to avoid paginating through all message history?
In regards to computing an unread message count, take a look at the Message Consumption Horizon and subtract the lastConsumedMessageIndex from the total number of messages in the list - 1.
For the messages list (in Python):
https://www.twilio.com/docs/api/ip-messaging/rest/messages#list-all-messages
# Download the Python helper library from twilio.com/docs/python/install
from twilio.rest.ip_messaging import TwilioIpMessagingClient
# Your Account Sid and Auth Token from twilio.com/user/account
account = "ACCOUNT_SID"
token = "AUTH_TOKEN"
client = TwilioIpMessagingClient(account, token)
service = client.services.get(sid="SERVICE_SID")
channel = service.channels.get(sid="CHANNEL_ID")
messages = channel.messages.list()
See also, Sending a Consumption Report (the example in JavaScript):
//determine the newest message index
var newestMessageIndex = activeChannel.messages.length ?
activeChannel.messages[activeChannel.messages.length-1].index : 0;
//check if we we need to set the consumption horizon
if (activeChannel.lastConsumedMessageIndex !== newestMessageIndex) {
activeChannel.updateLastConsumedMessageIndex(newestMessageIndex);
}