.. _how_to_do_common_tasks_2:

Package format 2 (recommended)
==============================

When writing a ROS package several tasks often need to be done.  These
pages give examples of how to handle most of the common ones.

.. note::

   These instructions are for ``<package format="2">``.

   If you are making small changes to a format 1 package, please use
   :ref:`how_to_do_common_tasks_1` instead.  If you are ready to
   upgrade a format 1 package to format 2, see:
   :ref:`migrating_from_format1_to_format2`.

Overview
--------

.. toctree::
   :maxdepth: 1

   catkin_overview

Resolving dependencies
----------------------

Packages almost always use features provided by other packages.
Describe all your direct dependencies.  Their transitive dependencies
on other packages are handled automatically by catkin.

.. toctree::
   :maxdepth: 1

   catkin_library_dependencies
   system_library_dependencies
   cpp_msg_dependencies
   python_module_dependencies


Building and installing targets
-------------------------------

*Build targets* are generated binaries, shared libraries, message
headers, and other objects.  Various targets require special handling.

.. toctree::
   :maxdepth: 1

   building_executables
   building_libraries
   building_msgs
   dynamic_reconfiguration
   installing_python
   installing_cmake
   installing_other


Configuring and running unit tests
----------------------------------

All configuration steps related to testing should be only done
conditionally when ``CATKIN_ENABLE_TESTING`` is set, which is true by
default.  Passing ``-DCATKIN_ENABLE_TESTING=0`` to CMake enables
configuring and building packages without any testing overhead.

.. toctree::
   :maxdepth: 1

   downloading_test_data
   gtest_configuration
   python_nose_configuration
   rostest_configuration
   run_tests

Migrating from package format 1
-------------------------------

When a format 1 package is revised, it probably makes sense to upgrade
its ``package.xml`` to format 2.

.. toctree::
   :maxdepth: 1

   migrating_from_format_1