I'm using the web console against my AMQ 5.2 instance successfully, except for I cannot see the content of all of my messages.
If I send a test message using the web console, I can see the sample text content, but I believe the vendor app I am working with has binary or byte array message content.
Is there something I need to do to be able to view this raw data?
Thanks,
To my knowledge, it is not possible to inspect messages in the Admin Console. You can get some statistics (like how many messages have been sent etc.).
ActiveMQ does not unmarshal messages when receiving them (for performance reasons, unmarshalling is rather expensive).
Thus, if you want to have some way to inspect messages for their content, you can basically do 2 things:
Write a consumer which registers for all topics/queues, through which you can see messages' content. Drawback: if you're using queue-based interaction, your "real" consumers will not get all messages
Write an activeMQ plugin which looks at the messages. Have a look at ActiveMQ's Logger Plugin. Then write your own (you'll need the sources to compile it) and load it with ActiveMQ (see the documentation on how to configure ActiveMQ to load plugins). You want to override the send() method which is called whenever someone sends a message to the broker. There you get a reference to the message and can access its content.
Neither of the two messages provides a convenient viewing-mechanism though. You'll have to resort to standard out, or write your own web-based access.
hawtio now shows first 256 chars of messages. Don't know if that is enough for you. Use browse() method.
Related
As part of my reporting I want to report on how many messages are still on the queue. If my system is running correctly I should have 0 or very few messages on the queue (100 for example, definitely not 1000)
What is the nest way to get the message count, or at least to see if there are say 1000 messages still on the queue. Would using activemq.prefetchSize in the header be the best way?
Using activemq.prefetchSize will not tell you how many messages are on a queue. In order to determine that you'll need to use one of ActiveMQ's management interfaces, e.g.:
Web Console
JMX
REST interface (scroll down to "Rest Management" section)
I took a dirty way to do this by accessing the page and then parsing the html
In our team, we exchange messages via RabbitMQ between two systems. The messages are encoded in protobuf (v3). We use NServiceBus on the sending and receiving side. We use the RabbitMQ management UI for monitoring the error queue. In production, we noticed that it is not easy to make sense of the payload of the messages in the error queue, which are base64-encoded.
What is the easiest way to get human-readable access to the messages in the error queue? We have full control over the decisions in both systems, and also discussed a switch to JSON-encoded messages (instead of protobuf). But we are otherwise happy with our protobuf-based implementation. Which is already implemented after all.
Protobuf v3 supports formatting as json, once you have the data parsed as IMessage (the base type for in-memory protobuf objects).
So you can convert a single message to be human readable as follows:
Use the webUI GetMessage function to get the message as base64 then requeue it
Convert the message back to protobuf binary via Convert.FromBase64String
Parse it back to an IMessage via ProtoMessageTypeGoesHere.Parser.ParseFrom(binaryData)
You can then convert the parsed message to Json via ToString() or Google.Protobuf.JsonFormatter.
As long as your error queue isn't going to be disrupted by the re-queuing (e.g. resetting of timestamps or reprocessing), you should be able to do this for all messages in the queue.
I wouldn't recommend using the management UI for this. A simple script or html page with a stomp client would be a lot easier to use and more error-proof, in my opinion.
However, to answer your question: to simply decode the message and replace the text, a simple javascript solution will work fine.
$(".msg-payload").text(atob($(".msg-payload").text()))
This will simply select the message field on the queue page on the RabbitMQ management UI and replace it with the decoded value (that's the function atob).
To use this, you can either run it from the console or add it as a bookmark in your browser. Simply use the code prefixed with javascript:, like so:
javascript:$(".msg-payload").text(atob($(".msg-payload").text()))
I wanted to write a plugin in OpenFire to inspect incoming messages between users and possibly stop this message from ongoing to the target recipient.
I can write a plugin that implement PacketInterceptor, but is there an api that supports blocking this packet from being sent or possibly modifying the body.
The rational for this is possibly offensive or illegal content. The times we live in :(
I found a packet filter created to do exactly this.
It can be found at https://www.igniterealtime.org/projects/openfire/plugins/packetfilter/readme.html
I am newbee in message broker area . Currently there are quiet a good no. of message broker are there(Rabbit-mq ,zeromq ,kafka and many more).
Want to know which thing to consider while opting for any message broker for backend architecture .
Route messages to one or more of many destinations
Transform messages to an alternative representation
Perform message aggregation, decomposing messages into multiple messages and sending them to their destination, then recomposing the responses into one message to return to the user
Interact with an external repository to augment a message or store it
Invoke Web services to retrieve data
Respond to events or errors
Provide content and topic-based message routing using the publish–subscribe pattern
https://en.wikipedia.org/wiki/Message_broker
Try to use RabbitMq, simple and fast.
Is it a good idea to send files with size about 1Mb through RabbitMQ? I want to send message in json format with binary fields corresponding to the files.
And how to do it properly using spring-amqp? Just by publishing object with next class?
class Message {
String field1;
byte[] fileField1;
byte[] fileField2;
}
I would suggest not only reading those links that were posted but also, doing some of your own experimentation. The thing I would be concerned about is performance at the service level and at the client level.
You might want to consider having a server host the files/data and allow rabbitmq just send the message to the consumer with the id of the message in it. So when your consumer gets the message, it sends an HTTP GET request to a service that requests the actual message payload. That way RabbitMQ stays lightweight. You can always add consumers and servers if you need.
That's my opinion without experimenting. You might find that it's still lighting fast with 1MB payloads. That's why I would say to experiment and find out for yourself.
Hope you find this helpful!