doc/source/projectconf.rst - buildstream - Git at Google

 .. _projectconf:


 Project Configuration
 =====================
 The project configuration file should be named ``project.conf`` and
 be located at the project root. It holds information such as Source
 aliases relevant for the sources used in the given project as well as
 overrides for the configuration of element types used in the project.

 Values specified in the project configuration override any of the
 default BuildStream project configuration, which is included
 :ref:`here <project_defaults>` for reference.


 .. _project_essentials:

 Essentials
 ----------


 Project Name
 ~~~~~~~~~~~~
 The first thing to setup in your ``project.conf`` should be the name
 of your project.

 .. code:: yaml

    name: my-project-name

 The project name will be used in user configuration and anywhere
 that a project needs to be specified.


 Element Path
 ~~~~~~~~~~~~
 To allow the user to structure their project nicely, BuildStream
 allows the user to specify a project subdirectory where element
 ``.bst`` files are stored.

 .. code:: yaml

    element-path: elements

 Note that elements are referred to by their relative paths, whenever
 elements are referred to in a ``.bst`` file or on the command line.


 Source Aliases
 ~~~~~~~~~~~~~~
 In order to abstract the download location of source code and
 any assets which need to be downloaded, and also as a matter of
 convenience, BuildStream allows one to create named aliases for
 URLs which are to be used in the individual ``.bst`` files.

 .. code:: yaml

    aliases:
      foo: git://git.foo.org/
      bar: http://bar.com/downloads/


 .. _project_essentials_artifacts:

 Artifact Server
 ~~~~~~~~~~~~~~~
 If you have setup an :ref:`artifact server <artifacts>` for your
 project then it is convenient to configure this in your ``project.conf``
 so that users need not have any additional configuration to communicate
 with an artifact share.

 .. code:: yaml

   artifacts:

     # A url from which to download prebuilt artifacts
     pull-url: https://foo.com/artifacts

     # A url to upload built artifacts to
     # (must point to the same repository as pull-url)
     push-url: artifacts@foo.com:artifacts

     # Specify the port number for pushing artifacts, if it's
     # not the default port 22
     push-port: 10000


 Plugin Paths
 ~~~~~~~~~~~~
 If your project includes any custom *Elements* or *Sources*, then
 the project relative subdirectory where these plugins are stored
 must be specified.

 .. code:: yaml

    plugins:

      elements:
      - plugins/local-elements
      - plugins/shared-elements

      sources:
      - plugins/local-sources


 Versioning
 ~~~~~~~~~~
 The BuildStream format is guaranteed to be backwards compatible
 with any earlier releases. The core YAML format, the format supported
 by various plugins, and the overall BuildStream release version are
 revisioned separately.

 The ``project.conf`` allows asserting the minimal required core
 format version and the minimal required version for individual
 plugins.

 .. code:: yaml

   required-versions:

     # The minimum base BuildStream format
     project: 0

     # The minimum version of the autotools element
     elements:
       autotools: 3


 .. _project_options:

 Options
 -------
 Options are how BuildStream projects can define parameters which
 can be configured by users invoking BuildStream to build your project.

 Options are declared in the ``project.conf`` in the main ``options``
 dictionary.

 .. code:: yaml

    options:
      debug:
        type: bool
        description: Whether to enable debugging
        default: False

 Users can configure those options when invoking BuildStream with the
 ``--option`` argument::

     $ bst --option debug True ...


 Common Properties
 ~~~~~~~~~~~~~~~~~
 All option types accept the following common attributes

 * ``type``

   Indicates the type of option to declare

 * ``description``

   A description of the meaning of the option

 * ``variable``

   Optionally indicate a :ref:`variable <format_variables>` name to
   export the option to. A string form of the selected option will
   be used to set the exported value.

   If used, this value will override any existing value for the
   variable declared in ``project.conf``, and will be overridden in
   the regular :ref:`composition order <format_composition>`.


 Boolean
 ~~~~~~~
 The ``bool`` option type allows specifying boolean values which
 can be cased in conditional expressions.


 **Declaring**

 .. code:: yaml

    options:
      debug:
        type: bool
        description: Whether to enable debugging
        default: False


 **Evaluating**

 Boolean options can be tested in expressions with equality tests:

 .. code:: yaml

    variables:
      enable-debug: False
      (?):
      - debug == True:
          enable-debug: True

 Or simply treated as truthy values:

 .. code:: yaml

    variables:
      enable-debug: False
      (?):
      - debug:
          enable-debug: True


 **Exporting**

 When exporting boolean options as variables, a ``True`` option value
 will be exported as ``1`` and a ``False`` option as ``0``


 Enumeration
 ~~~~~~~~~~~
 The ``enum`` option type allows specifying a string value
 with a restricted set of possible values.


 **Declaring**

 .. code:: yaml

    options:
      loglevel:
        type: enum
        description: The logging level
        values:
        - debug
        - info
        - warning
        default: info


 **Evaluating**

 Enumeration options must be tested as strings in conditional
 expressions:

 .. code:: yaml

    variables:
      enable-debug: False
      (?):
      - loglevel == "debug":
          enable-debug: True


 **Exporting**

 When exporting enumeration options as variables, the value is
 exported as a variable directly, as it is a simple string.


 Flags
 ~~~~~
 The ``flags`` option type allows specifying a list of string
 values with a restricted set of possible values.

 In contrast with the ``enum`` option type, the *default* value
 need not be specified and will default to an empty set.


 **Declaring**

 .. code:: yaml

    options:
      logmask:
        type: flags
        description: The logging mask
        values:
        - debug
        - info
        - warning
        default:
        - info


 **Evaluating**

 Flags type options can be tested in conditional expressions using
 a pythonic *in* syntax to test if an element is present in a set:

 .. code:: yaml

    variables:
      enable-debug: False
      (?):
      - ("debug" in logmask):
          enable-debug: True


 **Exporting**

 When exporting flags options as variables, the value is
 exported as a comma separated list of selected value strings.


 Architecture
 ~~~~~~~~~~~~
 The ``arch`` type option is special enumeration option which
 defaults to the result of `uname -m`, and does not support
 assigning any default in the project configuration.

 .. code:: yaml

    options:
      machine_arch:
        type: arch
        description: The machine architecture
        values:
        - arm
        - aarch64
        - i386
        - x86_64


 Architecture options can be tested with the same expressions
 as other Enumeration options.


 Element Mask
 ~~~~~~~~~~~~
 The ``element-mask`` option type is a special Flags option
 which automatically allows only element names as values.

 .. code:: yaml

    options:
      debug_elements:
        type: element-mask
        description: The elements to build in debug mode

 This can be convenient for automatically declaring an option
 which might apply to any element, and can be tested with the
 same syntax as other Flag options.


 .. code:: yaml

    variables:
      enable-debug: False
      (?):
      - ("element.bst" in debug_elements):
          enable-debug: True


 .. _project_defaults:

 Specifying Defaults
 --------------------
 The ``project.conf`` plays a role in defining elements by
 providing default values and also by overriding values declared
 by plugins on a plugin wide basis.

 See the :ref:`composition <format_composition>` documentation for
 more detail on how elements are composed.


 Variables
 ~~~~~~~~~
 The defaults for :ref:`Variables <format_variables>` used in your
 project is defined here.

 .. code:: yaml

    variables:
      prefix: "/usr"


 Environment
 ~~~~~~~~~~~
 The defaults environment for the build sandbox is defined here.

 .. code:: yaml

    environment:
      PATH: /usr/bin:/bin:/usr/sbin:/sbin

 Additionally, the special ``environment-nocache`` list which specifies
 which environment variables do not effect build output, and are thus
 not considered in the calculation of artifact keys can be defined here.

 .. code:: yaml

    environment-nocache:
    - MAXJOBS

 Note that the ``environment-nocache`` list only exists so that we can
 control parameters such as ``make -j ${MAXJOBS}``, allowing us to control
 the number of jobs for a given build without effecting the resulting
 cache key.


 Split Rules
 ~~~~~~~~~~~
 The project wide :ref:`split rules <public_split_rules>` defaults can
 be specified here.

 .. code:: yaml

    split-rules:
      devel:
      - |
        %{includedir}
      - |
        %{includedir}/**
      - |
        %{libdir}/lib*.a
      - |
        %{libdir}/lib*.la


 Element Overrides
 ~~~~~~~~~~~~~~~~~
 Base attributes declared by element default yaml files can be overridden
 on a project wide basis. The elements dictionary can be used to override
 variables, environments or plugin specific configuration data as shown below.


 .. code:: yaml

    elements:

      # Override default values for all autotools elements
      autotools:

        variables:
          bindir: "%{prefix}/bin"

        config:
          configure-commands: ...

        environment:
          PKG_CONFIG_PATH=%{libdir}/pkgconfig


 .. _project_builtin_defaults:

 Builtin Defaults
 ----------------
 BuildStream defines some default values for convenience, the default
 values overridden by your project's ``project.conf`` are presented here:

   .. literalinclude:: ../../buildstream/data/projectconfig.yaml
      :language: yaml
	.. _projectconf:


	Project Configuration
	=====================
	The project configuration file should be named ``project.conf`` and
	be located at the project root. It holds information such as Source
	aliases relevant for the sources used in the given project as well as
	overrides for the configuration of element types used in the project.

	Values specified in the project configuration override any of the
	default BuildStream project configuration, which is included
	:ref:`here <project_defaults>` for reference.


	.. _project_essentials:

	Essentials
	----------


	Project Name
	~~~~~~~~~~~~
	The first thing to setup in your ``project.conf`` should be the name
	of your project.

	.. code:: yaml

	name: my-project-name

	The project name will be used in user configuration and anywhere
	that a project needs to be specified.


	Element Path
	~~~~~~~~~~~~
	To allow the user to structure their project nicely, BuildStream
	allows the user to specify a project subdirectory where element
	``.bst`` files are stored.

	.. code:: yaml

	element-path: elements

	Note that elements are referred to by their relative paths, whenever
	elements are referred to in a ``.bst`` file or on the command line.


	Source Aliases
	~~~~~~~~~~~~~~
	In order to abstract the download location of source code and
	any assets which need to be downloaded, and also as a matter of
	convenience, BuildStream allows one to create named aliases for
	URLs which are to be used in the individual ``.bst`` files.

	.. code:: yaml

	aliases:
	foo: git://git.foo.org/
	bar: http://bar.com/downloads/


	.. _project_essentials_artifacts:

	Artifact Server
	~~~~~~~~~~~~~~~
	If you have setup an :ref:`artifact server <artifacts>` for your
	project then it is convenient to configure this in your ``project.conf``
	so that users need not have any additional configuration to communicate
	with an artifact share.

	.. code:: yaml

	artifacts:

	# A url from which to download prebuilt artifacts
	pull-url: https://foo.com/artifacts

	# A url to upload built artifacts to
	# (must point to the same repository as pull-url)
	push-url: artifacts@foo.com:artifacts

	# Specify the port number for pushing artifacts, if it's
	# not the default port 22
	push-port: 10000


	Plugin Paths
	~~~~~~~~~~~~
	If your project includes any custom Elements or Sources, then
	the project relative subdirectory where these plugins are stored
	must be specified.

	.. code:: yaml

	plugins:

	elements:
	- plugins/local-elements
	- plugins/shared-elements

	sources:
	- plugins/local-sources


	Versioning
	~~~~~~~~~~
	The BuildStream format is guaranteed to be backwards compatible
	with any earlier releases. The core YAML format, the format supported
	by various plugins, and the overall BuildStream release version are
	revisioned separately.

	The ``project.conf`` allows asserting the minimal required core
	format version and the minimal required version for individual
	plugins.

	.. code:: yaml

	required-versions:

	# The minimum base BuildStream format
	project: 0

	# The minimum version of the autotools element
	elements:
	autotools: 3



	.. _project_options:

	Options
	-------
	Options are how BuildStream projects can define parameters which
	can be configured by users invoking BuildStream to build your project.

	Options are declared in the ``project.conf`` in the main ``options``
	dictionary.

	.. code:: yaml

	options:
	debug:
	type: bool
	description: Whether to enable debugging
	default: False

	Users can configure those options when invoking BuildStream with the
	``--option`` argument::

	$ bst --option debug True ...


	Common Properties
	~~~~~~~~~~~~~~~~~
	All option types accept the following common attributes

	* ``type``

	Indicates the type of option to declare

	* ``description``

	A description of the meaning of the option

	* ``variable``

	Optionally indicate a :ref:`variable <format_variables>` name to
	export the option to. A string form of the selected option will
	be used to set the exported value.

	If used, this value will override any existing value for the
	variable declared in ``project.conf``, and will be overridden in
	the regular :ref:`composition order <format_composition>`.


	Boolean
	~~~~~~~
	The ``bool`` option type allows specifying boolean values which
	can be cased in conditional expressions.


	Declaring

	.. code:: yaml

	options:
	debug:
	type: bool
	description: Whether to enable debugging
	default: False


	Evaluating

	Boolean options can be tested in expressions with equality tests:

	.. code:: yaml

	variables:
	enable-debug: False
	(?):
	- debug == True:
	enable-debug: True

	Or simply treated as truthy values:

	.. code:: yaml

	variables:
	enable-debug: False
	(?):
	- debug:
	enable-debug: True


	Exporting

	When exporting boolean options as variables, a ``True`` option value
	will be exported as ``1`` and a ``False`` option as ``0``


	Enumeration
	~~~~~~~~~~~
	The ``enum`` option type allows specifying a string value
	with a restricted set of possible values.


	Declaring

	.. code:: yaml

	options:
	loglevel:
	type: enum
	description: The logging level
	values:
	- debug
	- info
	- warning
	default: info


	Evaluating

	Enumeration options must be tested as strings in conditional
	expressions:

	.. code:: yaml

	variables:
	enable-debug: False
	(?):
	- loglevel == "debug":
	enable-debug: True


	Exporting

	When exporting enumeration options as variables, the value is
	exported as a variable directly, as it is a simple string.


	Flags
	~~~~~
	The ``flags`` option type allows specifying a list of string
	values with a restricted set of possible values.

	In contrast with the ``enum`` option type, the default value
	need not be specified and will default to an empty set.


	Declaring

	.. code:: yaml

	options:
	logmask:
	type: flags
	description: The logging mask
	values:
	- debug
	- info
	- warning
	default:
	- info


	Evaluating

	Flags type options can be tested in conditional expressions using
	a pythonic in syntax to test if an element is present in a set:

	.. code:: yaml

	variables:
	enable-debug: False
	(?):
	- ("debug" in logmask):
	enable-debug: True


	Exporting

	When exporting flags options as variables, the value is
	exported as a comma separated list of selected value strings.


	Architecture
	~~~~~~~~~~~~
	The ``arch`` type option is special enumeration option which
	defaults to the result of `uname -m`, and does not support
	assigning any default in the project configuration.

	.. code:: yaml

	options:
	machine_arch:
	type: arch
	description: The machine architecture
	values:
	- arm
	- aarch64
	- i386
	- x86_64


	Architecture options can be tested with the same expressions
	as other Enumeration options.


	Element Mask
	~~~~~~~~~~~~
	The ``element-mask`` option type is a special Flags option
	which automatically allows only element names as values.

	.. code:: yaml

	options:
	debug_elements:
	type: element-mask
	description: The elements to build in debug mode

	This can be convenient for automatically declaring an option
	which might apply to any element, and can be tested with the
	same syntax as other Flag options.


	.. code:: yaml

	variables:
	enable-debug: False
	(?):
	- ("element.bst" in debug_elements):
	enable-debug: True



	.. _project_defaults:

	Specifying Defaults
	--------------------
	The ``project.conf`` plays a role in defining elements by
	providing default values and also by overriding values declared
	by plugins on a plugin wide basis.

	See the :ref:`composition <format_composition>` documentation for
	more detail on how elements are composed.


	Variables
	~~~~~~~~~
	The defaults for :ref:`Variables <format_variables>` used in your
	project is defined here.

	.. code:: yaml

	variables:
	prefix: "/usr"


	Environment
	~~~~~~~~~~~
	The defaults environment for the build sandbox is defined here.

	.. code:: yaml

	environment:
	PATH: /usr/bin:/bin:/usr/sbin:/sbin

	Additionally, the special ``environment-nocache`` list which specifies
	which environment variables do not effect build output, and are thus
	not considered in the calculation of artifact keys can be defined here.

	.. code:: yaml

	environment-nocache:
	- MAXJOBS

	Note that the ``environment-nocache`` list only exists so that we can
	control parameters such as ``make -j ${MAXJOBS}``, allowing us to control
	the number of jobs for a given build without effecting the resulting
	cache key.


	Split Rules
	~~~~~~~~~~~
	The project wide :ref:`split rules <public_split_rules>` defaults can
	be specified here.

	.. code:: yaml

	split-rules:
	devel:
	- \|
	%{includedir}
	- \|
	%{includedir}/**
	- \|
	%{libdir}/lib*.a
	- \|
	%{libdir}/lib*.la


	Element Overrides
	~~~~~~~~~~~~~~~~~
	Base attributes declared by element default yaml files can be overridden
	on a project wide basis. The elements dictionary can be used to override
	variables, environments or plugin specific configuration data as shown below.


	.. code:: yaml

	elements:

	# Override default values for all autotools elements
	autotools:

	variables:
	bindir: "%{prefix}/bin"

	config:
	configure-commands: ...

	environment:
	PKG_CONFIG_PATH=%{libdir}/pkgconfig


	.. _project_builtin_defaults:

	Builtin Defaults
	----------------
	BuildStream defines some default values for convenience, the default
	values overridden by your project's ``project.conf`` are presented here:

	.. literalinclude:: ../../buildstream/data/projectconfig.yaml
	:language: yaml