.. _autospec-about:

Autospec
########

``autospec`` is a tool to assist in the automated creation and maintenance of
RPM packaging in |CL-ATTR|. Where a standard RPM build process using ``rpmbuild``
requires a tarball and .spec file to start, ``autospec`` requires only a tarball
and package name to start.

How autospec works
******************

``autospec`` attempts to infer the requirements of the .spec file by analyzing
the source code and :file:`Makefile` information. It will continuously run
updated builds based on new information discovered from build failures until it
has a complete and valid .spec file. Although not required, you can influence
the behavior of ``autospec`` by providing :ref:`control files <control-files>`.

The basic process is described in the following steps:

#. The :command:`make autospec` command generates a .spec based on
   analysis of code and control files, if present.

#. ``autospec`` creates a ``build root`` with ``mock`` config.

#. ``autospec`` attempts to build an RPM from the generated .spec.

#. ``autospec`` detects any missed declarations in the .spec.

#. If build errors occur, ``autospec`` will scan the build log to try and detect
   the root cause.

#. If ``autospec`` detects the root cause and knows how to continue, it will restart the build
   automatically at step 1 with updated build instructions.

#. Otherwise, ``autospec`` will stop the build for user inspection and editing of control files
   to resolve the errors. The user resumes the process at step 1 after errors are resolved.

Following these steps, ``autospec`` continues to rebuild the package, based on
new information discovered from build failures, until it has a valid .spec. If
no build errors occur, RPM packages are successfully built.

.. _control-files:

Control files
*************

It is possible to influence the behavior of ``autospec`` by providing control
files. These files may be used to alter the default behavior of the configure
routine, to blacklist build dependencies, etc. Control files must be located
in the same directory as the resulting .spec.

Table 1 shows control files used to control dependencies, for example.

.. list-table:: **Table 1. Control files to control dependencies**
   :widths: 20 80
   :header-rows: 1

   * - Filename
     - Description
   * - buildreq_add
     - Each line in the file provides the name of a package to add as a
       build dependency to the .spec.
   * - buildreq_ban
     - Each line in the file is a build dependency that under no
       circumstance should be automatically added to the build dependencies.
       This is useful to block automatic configuration routines adding
       undesired functionality, or to omit any automatically discovered
       dependencies during tarball scanning.
   * - pkgconfig_add
     - Each line in the file is assumed to be a pkgconfig() build
       dependency. Add the pkg-config names here, as ``autospec`` will
       automatically transform the names into their ``pkgconfig($name)``
       style when generating the .spec.
   * - pkgconfig_ban
     - Each line in this file is a pkgconfig() build dependency that should
       not be added automatically to the build, much the same as
       `` buildreq_ban``. As with ``pkgconfig_add``, these names are
       automatically transformed by ``autospec`` into their correct
       ``pkgconfig($name))`` style.
   * - requires_add
     - Each line in the file provides the name of a package to add as a
       runtime dependency to the .spec.
   * - requires_ban
     - Each line in the file is a runtime dependency that under no
       circumstance should be automatically added to the runtime
       dependencies. This is useful to block automatic configuration
       routines adding undesired functionality, or to omit any automatically
       discovered dependencies during tarball scanning.

Further control of the build can be achieved through the use of the
``options.conf`` file. If this file does not exist, it is created by
``autospec`` with default values. If certain deprecated configuration
files exists ``autospec`` will use the value indicated by those files and
remove them.

For a comprehensive list of control files, view the `autospec readme`_.

Related topics
**************

* :ref:`autospec`
* :ref:`mixer`
* :ref:`mixin`

.. _autospec readme: https://github.com/clearlinux/autospec
