Example1

Under Development (Do Not Use, Not Finished)

This is a simple example on how to create tasks in DUNE. There are three parts in in this exercise:

• Producer: will create a static variable "temperature" and set a value for it then it will be send as an IMC message.
• Consumer: will keep searching in the BUS for the variable "temperature" and print it on the screen.
• ini file: where we set the instructions for DUNE, for testing our tasks.

Creating Tasks

Assume DH> = $home/dune

Producer

First, we start by creating the simple HelloWorld task. The general structure of creating a task is

DH> python programs/scripts/dune-create-task.py DH> AuthorName NameOfTheTask

where, executing the python script 'dune-create-task.py' located in the DH>programs/scripts will create a task with task name "NameOfTheTask" in the Dune home directory (DH>). The AuthorName is to identify the author who is creating the task. The task will be created in the source directory DH>src/

For example, executing the following command
DH> python programs/scripts/dune-create-task.py . DuneAuthor HelloWorld

will generate the output

Created DUNE task in './src/HelloWorld'

Producer

Then we open the file in a text editor and copy the following code
```sh
#include <DUNE/DUNE.hpp>

namespace Workshop
{
  namespace Producer
  {
    using DUNE_NAMESPACES;

    struct Task: public DUNE::Tasks::Periodic
    {
      Task(const std::string& name, Tasks::Context& ctx):
        DUNE::Tasks::Periodic(name, ctx)
      {
      }

      void
      onUpdateParameters(void)
      {
      }

      void
      onEntityReservation(void)
      {
      }

      void
      onEntityResolution(void)
      {
      }

      void
      onResourceAcquisition(void)
      {
      }

      void
      onResourceInitialization(void)
      {
      }

      void
      onResourceRelease(void)
      {
      }

      void
      task(void)
      {
        IMC::Temperature temperature;
        temperature.setSourceEntity(getEntityId());
        temperature.value = 45.0;
        dispatch(temperature);
      }
    };
  }
}

DUNE_TASK

Consumer

In the same way, we create the task by

./dune-create-task -p ../dune/src -o 'Ricardo Martins' -t Workshop -n
Consumer

Again we copy the following code in a text editor

#include <DUNE/DUNE.hpp>

namespace Workshop
{
  namespace Consumer
  {
    using DUNE_NAMESPACES;

    struct Task: public DUNE::Tasks::Task
    {
      Task(const std::string& name, Tasks::Context& ctx):
        DUNE::Tasks::Task(name, ctx)
      {
        bind<IMC::Temperature>(this);
      }

      void
      onUpdateParameters(void)
      {
      }

      void
      onEntityReservation(void)
      {
      }

      void
      onEntityResolution(void)
      {
      }

      void
      onResourceAcquisition(void)
      {
      }

      void
      onResourceInitialization(void)
      {
      }

      void
      onResourceRelease(void)
      {
      }

      void
      consume(const IMC::Temperature* msg)
      {
        inf("temperature is %f", msg->value);
      }

      void
      onMain(void)
      {
        while (!stopping())
        {
          waitForMessages(1.0);
        }
      }
    };
  }
}

DUNE_TASK

Compiling

Because we changed the files, we have to rebuild the list of tasks before compiling

make rebuild_chache

Now, we can compile

make

Testing

Create the file ../dune/etc/development/workshop.ini which has the following lines

[Include ../common/transports.ini]

[Workshop.Producer]
Enabled = Always
Entity Label = Producer

[Workshop.Consumer]
Enabled = Always
Entity Label = Consumer

[Transports.Logging]
Enabled = Always
Entity Label = Logger
Transports = Temperature

then run

./dune –c development/workshop