Python library for parsing and manipulating RPM spec files. Main focus is on modifying existing spec files, any change should result in a minimal diff.
Originally, rebase-helper provided an API for spec file modifications that was also used by packit. The goal of this project is to make the interface more general and convenient to use by not only packit but also by other Python projects that need to interact with RPM spec files.
Section is a spec file section, it has a well-defined name that starts with % character and that can optionally be followed by arguments.
In this library, the starting % of section name is omitted for convenience.
There is a special section internally called %package
, often also referred to as preamble, and it represents the content of the spec file that precedes the first named section (usually %description
). This section contains the main package metadata (tags). Metadata of subpackages are defined in subsequent %package
sections, that are not anonymous and are always followed by arguments specifying the name of the subpackage (e.g. %package doc
or %package -n completely-different-subpackage-name
).
Tag represents a single item of metadata of a package. It has a well-defined name and a value. Tags are defined in %package
sections.
For the purposes of this library, a tag can have associated comments. These are consecutive comment lines directly above the tag definition in a spec file.
Source is a source file or a downstream patch defined by a Source
/Patch
tag or by an entry in %sourcelist
/%patchlist
section.
Source can be local, specified by a filename, or remote, specified by a URL. Local sources should be located in a directory referred to as sourcedir
. Remote sources should be downloaded to this directory.
Sources defined by tags can be explicitly numbered, e.g. Source0
or Patch999
, otherwise implicit numbering takes place and source numbers are auto-assigned in a sequential manner.
Prep macros are macros that often appear in (and only in, they don't make sense anywhere else) %prep
section.
4 such macros are recognized by this library, %setup
, %patch
, %autosetup
and %autopatch
. A typical spec file uses either %autosetup
or a combination of %setup
and %patch
or %autopatch
.
Full documentation generated from code.
The following examples should cover use cases required by packit.
from specfile import Specfile
# using an absolute path
specfile = Specfile('/tmp/test.spec')
# using a relative path and a different sourcedir
specfile = Specfile('test.spec', sourcedir='/tmp/sources')
# if the spec file happens to be modified externally, it can be reloaded
specfile.reload()
# no autosave
specfile = Specfile('test.spec')
...
# saving explicitly when needed
specfile.save()
# enabling autosave, changes are saved immediately after any modification
specfile = Specfile('test.spec', autosave=True)
# as a context manager, saving is performed at context exit
with Specfile('test.spec') as specfile:
...
# override macros loaded from system macro files
specfile = Specfile('test.spec', macros=[('fedora', '38'), ('dist', '.fc38')])
# undefine a system macro (in case it's defined)
specfile = Specfile('test.spec', macros=[('rhel', None)])
with specfile.sections() as sections:
# replacing the content of a section
sections.prep = ['%autosetup -p1']
# removing a section
del sections.changelog
# swapping two sections
sections[1], sections[2] = sections[2], sections[1]
# accessing a section with arguments
print(sections.get('package devel'))
# inserting a line into a section
sections.build.insert(0, 'export VERBOSE=1')
# copying a section from one specfile to another
with specfile1.sections() as sections1, with specfile2.sections() as sections2:
sections2.changelog[:] = sections1.changelog
# accessing tags in preamble
with specfile.tags() as tags:
# name of the first tag
print(tags[0].name)
# raw value of the first tag
print(tags[0].value)
# expanded value of the first tag
print(tags[0].expanded_value)
# comments associated with the first tag
print(tags[0].comments)
# value of a tag by name
print(tags.url)
tags.url = 'https://example.com'
# accessing tags in subpackages
with specfile.tags('package devel') as tags:
print(tags.requires)
# working with changelog
with specfile.changelog() as changelog:
# most recent changelog entry
print(changelog[-1])
# making changes
changelog[1].content.append('- another line')
# removing the oldest entry
del changelog[0]
# working with macros in %prep section, supports %setup, %patch, %autosetup and %autopatch
from specfile.prep import AutosetupMacro
with specfile.prep() as prep:
# name of the first macro
print(prep.macros[0].name)
# checking if %autosetup is being used
print('%autosetup' in prep)
print(AutosetupMacro in prep)
# changing macro options
prep.autosetup.options.n = '%{srcname}-%{version}'
# adding a new %patch macro
prep.add_patch_macro(28, p=1, b='.test')
# removing an existing %patch macro by name
del prep.patch0
# this works for both '%patch0' and '%patch -P0'
prep.remove_patch_macro(0)
# getting version and release
print(specfile.version)
print(specfile.release)
# setting version and release
specfile.version = '2.1'
specfile.release = '3'
# setting both at the same time (release defaults to 1)
specfile.set_version_and_release('2.1', release='3')
# setting version while trying to preserve macros
specfile.set_version_and_release('2.1', preserve_macros=True)
To bump release and add a new changelog entry, you could use the following code:
from specfile import Specfile
with Specfile("example.spec") as spec:
spec.release = str(int(spec.expanded_release) + 1)
spec.add_changelog_entry("- Bumped release for test purposes")
# adding a new entry, author is automatically determined
# (using the same heuristics that rpmdev-packager uses) if possible
# this function already honors autochangelog
specfile.add_changelog_entry('- New upstream release 2.1')
# adding a new entry, specifying author and timestamp explicitly
specfile.add_changelog_entry(
'- New upstream release 2.1',
author='Nikola Forró',
email='[email protected]',
timestamp=datetime.date(2021, 11, 20),
)
if specfile.has_autochangelog:
# do something
with specfile.sources() as sources:
# expanded location of the first source
print(sources[0].expanded_location)
# adding a source
sources.append('tests.tar.gz')
with specfile.patches() as patches:
# modifying location of the first patch
patches[0].location = 'downstream.patch'
# removing comments associated with the last patch
patches[-1].comments.clear()
# adding and removing patches
patches.append('another.patch')
del patches[2]
# inserting a patch with a specific number
patches.insert_numbered(999, 'final.patch')
# adding a single patch
specfile.add_patch('necessary.patch', comment='a human-friendly comment to the patch')
print(specfile.name)
print(specfile.license)
print(specfile.summary)
specfile.url = 'https://example.com'
Note that if you want to access multiple tag values, it may be noticeably faster to do it using the tags
context manager:
# same as above, but roughly 4x times faster (parsing/saving happens only once)
with specfile.tags() as tags:
print(tags.name.value)
print(tags.license.value)
print(tags.summary.value)
tags.url.value = 'https://example.com'
If you don't need write access, you can use the content
property of context managers and avoid the with
statement:
# no changes done to the tags object will be saved
tags = specfile.tags().content
print(tags.version.expanded_value)
print(tags.release.expanded_value)
# number of sources
print(len(specfile.sources().content))
Macro definitions, tags, %sourcelist
/%patchlist
entries and sources/patches have a valid
attribute. An entity is considered valid if it isn't present in a false branch of any condition.
Consider the following in a spec file:
%if 0%{?fedora} >= 36
Recommends: %{name}-selinux
%endif
Provided there are no other Recommends
tags, the following would print True
or False
depending on the value of the %fedora
macro:
with specfile.tags() as tags:
print(tags.recommends.valid)
You can define macros or redefine/undefine system macros using the macros
argument of the constructor or by modifying the macros
attribute of a Specfile
instance.
The same applies to %ifarch
/%ifos
statements:
%ifarch %{java_arches}
BuildRequires: java-devel
%endif
Provided there are no other BuildRequires
tags, the following would print True
in case the current platform was part of %java_arches
:
with specfile.tags() as tags:
print(tags.buildrequires.valid)
To override this, you would have to redefine the %_target_cpu
system macro (or %_target_os
in case of %ifos
).
Here is a demo showcasing the Specfile.update_tag()
method and its use cases: