feat: build srpm with meson

Add a "build_srpm" meson build option. When true, meson will attempt to
build a SRPM using the current source root as the RPM source.

CONTRIBUTING.md

@@ -118,7 +118,13 @@ sudo go run ./cmd/yggd --config ./data/yggdrasil/config.toml
 
 Many default paths (such as Prefix, BinDir, LocalstateDir, etc), as well as some
 other compile-time constants, can be specified by providing a linker `-X` flag
-argument. See the `Makefile` or `constants.go` for a complete list. 
+argument. See the [meson built-in
+options](https://mesonbuild.com/Builtin-options.html) or
+`internal/constants/constants.go` for a complete list.
+
+It is also possible to compile `yggd` and all additional programs in this
+project into an RPM suitable for installation on Fedora-based distributions. See
+the README in `dist/srpm` for details.
 
 ## Debugging `yggd`
 

dist/meson.build

@@ -0,0 +1,3 @@
+if get_option('build_srpm')
+  subdir('srpm')
+endif

dist/srpm/README.md

@@ -0,0 +1,19 @@
+This directory includes files necessary to build an SRPM as part of the normal
+`meson compile` step.
+
+# Usage
+
+1. Set the `build_srpm` build option to `True` when setting up the project:
+   `meson setup -Dbuild_srpm=True builddir`
+2. Compile the `srpm` target: `meson compile srpm -C builddir`
+
+An SRPM will be built and can be found in `builddir/dist/srpm`. This SRPM will
+need to be rebuilt into a binary in order to install it. To rebuild it using
+`mock` on Fedora, for example, run:
+
+```
+mock --rebuild ./builddir/dist/srpm/*.src.rpm
+```
+
+The RPM built by `mock` can be found (typically) in
+`/var/run/mock/<root-name>/results`.

dist/srpm/meson.build

@@ -0,0 +1,45 @@
+git = find_program('git')
+rpmbuild = find_program('rpmbuild')
+tar = find_program('tar')
+bash = find_program('bash')
+
+commit = run_command(git, 'rev-parse', 'HEAD', capture: true, check: true).stdout().strip()
+
+if get_option('vendor')
+run_command([bash, files(meson.project_source_root() / 'build-aux' / 'vendor.sh')], check: true)
+endif
+
+build_root_basename = meson.project_build_root().split('/').get(-1)
+tarball = custom_target('tarball',
+  command: [
+    tar,
+    '--create',
+    '--gzip',
+    '--absolute-names',
+    '--file', '@OUTPUT@',
+    '--transform', 's+@0@+@1@-@2@+'.format(meson.project_source_root(), meson.project_name(), commit),
+    '--exclude', build_root_basename,
+    '--exclude', '.git',
+    '--exclude', '.vscode',
+    '--exclude', '.github',
+    '--exclude', '.copr',
+    meson.project_source_root()
+  ],
+  output: '@0@-@[email protected]'.format(meson.project_name(), commit)
+)
+
+specfile = configure_file(
+  input: 'yggdrasil.spec.in',
+  output: '@BASENAME@',
+  configuration: {
+    'COMMIT': commit,
+    'VERSION': meson.project_version(),
+  }
+)
+
+run_target('srpm',
+  command: [rpmbuild, '-bs', '--define', 'commit @0@'.format(commit), '--define', '_srcrpmdir @0@'.format(meson.current_build_dir()), '--define', '_sourcedir @0@'.format(meson.current_build_dir()), specfile],
+  depends: [
+    tarball
+  ]
+)

dist/srpm/yggdrasil.spec.in

@@ -0,0 +1,107 @@
+# This RPM spec file exists primarily to enable CI/CD pipelines and automatic
+# testing of built RPMs. This RPM can be used as a suitable baseline for a
+# proper distribution package, but changes should be made to suit the needs of
+# the package.
+#
+# See https://src.fedoraproject.org/rpms/yggdrasil/blob/rawhide/f/yggdrasil.spec
+# for a better example of a downstream distribution packaging example.
+
+%bcond_without check
+
+# https://github.com/redhatinsights/yggdrasil
+%global goipath         github.com/redhatinsights/yggdrasil
+%global commit          @COMMIT@
+%global shortcommit     %(c=%{commit}; echo ${c:0:7})
+
+%if 0%{?fedora}
+%gometa -f
+%else
+%gometa
+%endif
+
+# Manually redefine %%dist to work around an issue in COPR where the build root
+# that creates the srpm does not define a value for %%dist. This should *NOT* be
+# carried in downstream; this is strictly an upstream/COPR/CI workaround.
+%if "%{dist}" == ""
+%global dist %{distprefix}.fc%{fedora}
+%endif
+
+%if 0%{?fedora}
+%global setup_flags -Dvendor=False -Dexamples=True
+%else
+%global setup_flags -Dvendor=True -Dexamples=True
+%endif
+
+%global common_description %{expand:
+yggdrasil is a system daemon that subscribes to topics on an MQTT broker and
+routes any data received on the topics to an appropriate child "worker" process,
+exchanging data with its worker processes through a D-Bus message broker.}
+
+%global golicenses      LICENSE
+%global godocs          CONTRIBUTING.md README.md
+
+Name:           yggdrasil
+Version:        @VERSION@
+Release:        0%{?dist}
+Summary:        Remote data transmission and processing client
+
+License:        GPL-3.0-only
+URL:            %{gourl}
+Source:         %{gosource}
+
+BuildRequires:  systemd-rpm-macros
+BuildRequires:  meson
+BuildRequires:  pkgconfig(dbus-1)
+BuildRequires:  pkgconfig(systemd)
+BuildRequires:  pkgconfig(bash-completion)
+
+%description %{common_description}
+
+%gopkg
+
+%prep
+%if 0%{?fedora}
+%goprep
+%else
+%goprep -k
+%endif
+
+%if 0%{?fedora}
+%generate_buildrequires
+%go_generate_buildrequires
+%endif
+
+%build
+%undefine _auto_set_build_flags
+export %gomodulesmode
+%{?gobuilddir:export GOPATH="%{gobuilddir}:${GOPATH:+${GOPATH}:}%{?gopath}"}
+%meson %setup_flags "-Dgobuildflags=[%(echo %{expand:%gocompilerflags} | sed -e s/"^"/"'"/ -e s/" "/"', '"/g -e s/"$"/"'"/), '-tags', '"rpm_crashtraceback\ ${BUILDTAGS:-}"', '-a', '-v', '-x']" -Dgoldflags='%{?currentgoldflags} -B 0x%(head -c20 /dev/urandom|od -An -tx1|tr -d " \n") -compressdwarf=false -linkmode=external -extldflags "%{build_ldflags} %{?__golang_extldflags}"'
+%meson_build
+
+%global gosupfiles ./ipc/com.redhat.Yggdrasil1.Dispatcher1.xml ./ipc/com.redhat.Yggdrasil1.Worker1.xml
+%install
+%meson_install
+%gopkginstall
+
+%if %{with check}
+%check
+%gocheck
+%endif
+
+%files
+%license LICENSE
+%doc CONTRIBUTING.md README.md
+%{_bindir}/*
+%{_libexecdir}/%{name}/*
+%config(noreplace) %{_sysconfdir}/%{name}
+%{_unitdir}/*
+%{_userunitdir}/*
+%{_datadir}/bash-completion/completions/*
+%{_datadir}/dbus-1/{interfaces,system-services,system.d}/*
+%{_datadir}/doc/%{name}/*
+%{_mandir}/man1/*
+
+%gopkgfiles
+
+%changelog
+%autochangelog

meson.build

@@ -37,6 +37,7 @@ subdir('cmd/yggd')
 subdir('data')
 subdir('dbus')
 subdir('doc')
+subdir('dist')
 subdir('ipc')
 
 if get_option('examples')

meson_options.txt

@@ -4,3 +4,4 @@ option('vendor', type: 'boolean', value: false, description: 'Bundle go module d
 option('examples', type: 'boolean', value: false, description: 'Build and install the example workers')
 option('gobuildflags', type: 'array', value: ['-buildmode', 'pie'], description: 'Additional build flags to be passed to the Go compiler')
 option('goldflags', type: 'string', value: '', description: 'Additional linker flags to be passed to the Go compiler')
+option('build_srpm', type: 'boolean', value: false, description: 'Enable SRPM builds')