Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Update README #296

Merged
merged 2 commits into from
Oct 27, 2023
Merged

Update README #296

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
567e872
Remove WIP note and caveats section
nforro Oct 27, 2023
c54a12f
Document validity of entities
nforro Oct 27, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
40 changes: 35 additions & 5 deletions README.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2,8 +2,6 @@

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.

This project is still a work in progress.

## Motivation

Originally, [rebase-helper](https://github.com/rebase-helper/rebase-helper/) provided an API for spec file modifications that was also used by [packit](https://github.com/packit/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.
Expand Down Expand Up @@ -252,11 +250,43 @@ print(tags.release.expanded_value)
print(len(specfile.sources().content))
```

## Caveats
### Validity

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:

```specfile
%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:

```python
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:

```specfile
%ifarch %{java_arches}
BuildRequires: java-devel
%endif
```

### RPM macros
Provided there are no other `BuildRequires` tags, the following would print `True` in case the current platform was part of `%java_arches`:

```python
with specfile.tags() as tags:
print(tags.buildrequires.valid)
```

specfile uses RPM for parsing spec files and macro expansion. Unfortunately, macros are always stored in a global context, which poses a problem for multiple instances of Specfile.
To override this, you would have to redefine the `%_target_cpu` system macro (or `%_target_os` in case of `%ifos`).

## Videos

Expand Down