Taskmixer
A simple solution to dispatch command strings over a local network using RabbitMQ.
In taskmixer we have a command producer (see taskmixer.producer project) that simply appends a string command to a RabbitMQ queue, and one or more command consumers (see taskmixer.consumer project) that wait for commands and execute them upon receipt. In the following we will call task a command string such as ls -l.
Producer and consumers may be on the same or on different machines.
RabbitMQ ensures that tasks are not lost even if consumers die or the machine containing the RabbitMQ server is rebooted.
Note that taskmixer does not handle the sharing of data but just the dispatch of tasks. To share data you might use NFS.
How to build the applications
git clone https://github.com/acco93/taskmixer.git
cd taskmixer
cd taskmixer.core
gradle build
cd ../
cd taskmixer.producer
gradle build
cd ../
cd taskmixer.consumer
gradle build
cd ../
mkdir -p build
cp taskmixer.producer/build/libs/txp-1.0.jar build/txp.jar
cp taskmixer.consumer/build/libs/txc-1.0.jar build/txc.jar
Now the directory build contains the task producer application txp.jar and the task consumer application txc.jar
Setup RabbitMQ
Producer side
Install a RabbitMQ server
sudo apt install rabbitmq-server
You might need to create an account
sudo rabbitmqctl add_user username password
sudo rabbitmqctl set_user_tags username administrator
sudo rabbitmqctl set_permissions -p / username ".*" ".*" ".*"
Check https://www.rabbitmq.com/rabbitmqctl.8.html#User_Management for more details.
Now you can send tasks to the queue from any machine in the local network by running
java -jar txp.jar 'ls -l' -u username -p password -i 192.168.xxx.xxx
The above line sends the task ls -l to a RabbitMQ server located at IP 192.168.xxx.xxx
By specifying the -w flag, the producer can wait for results printed to the standard output due to the command, if any.
java -jar txp-1.0.jar 'i=0; while [ $i -lt 10 ]; do echo $i; sleep 1; i=$[$i+1]; done' -u username -p password -i 192.168.xxx.xxx -w
By using the -b flag, the command is broadcast to all available consumers.
java -jar txp-1.0.jar 'ls -l' -u username -p password -i 192.168.xxx.xxx -b
Note that -w and -b together are currently not supported.
Consumer side
We can wait for tasks by using
java -jar txc.jar -u username -p password -i 192.168.xxx.xxx
Consumers process one task at a time. RabbitMQ dispatches tasks to the first available consumer by following a round robin strategy.
Convert to eclipse project
The repository can be easily converted into an eclipse project by using gradle
cd taskmixer
cd taskmixer.core/ && gradle eclipse && cd ..
cd taskmixer.producer/ && gradle eclipse && cd ..
cd taskmixer.consumer/ && gradle eclipse && cd ..
After that, go to eclipse File -> Import -> General -> Existing Projects into Workspace -> Select root directory browse selecting the git repository