Add Live ISO sources to Git (#1160)

## Problem

The Live ISO sources are not maintained at GitHub, that makes the
development complicated:

- Cannot track the changes easily, working with history in OBS is
limited and more complicated than with Git
- Changing files in tarballs is difficult, you have to unpack it, modify
a file and then manually compress back with correct parameters
- Building the Live ISO locally is not trivial

## Solution

- Move the sources into the `/live` subdirectory
- Add GitHub action for automatic submission from `master` to the
[systemsmanagement:Agama:Staging](https://build.opensuse.org/project/show/systemsmanagement:Agama:Staging)
OBS project
- Allow running the ISO build locally via `make build`

## Changes

The individual files were not touched, I just copied them from the
current OBS project. I only moved the `fw_cleanup.rb` script to the
`/tmp` directory as the script is temporary and it is deleted at the end
of the ISO build.

- All Kiwi tarballs were unpacked to Git
- Simple `make` builds the sources to the `dist` subdirectory and builds
the tarballs
- The ISO can be built locally using `make build`
- Updated/extended the documentation in README.md (There are two
README.md files, the main in `/live` which documents the details and the
`/live/src/README.md` which is copied to OBS. Mostl importantly it says
"do not touch this in OBS, use GitHub".)

## Testing

- Tested manually
- The autosubmission works (see the [GitHub action
log](https://github.com/lslezak/agama/actions/runs/8780447151/job/24090382501))
- The built ISO works (tested in my [agama-live
branch](https://build.opensuse.org/package/show/home:lslezak:branches:systemsmanagement:Agama:Staging/agama-live)
project)
- Local build works as well

---------

Co-authored-by: Imobach González Sosa <igonzalezsosa@suse.com>

.github/workflows/obs-staging-live.yml

@@ -0,0 +1,58 @@
+name: Submit agama-live
+
+on:
+  # runs on pushes targeting the default branch
+  push:
+    branches:
+      - master
+    paths:
+      # run only when a live ISO source is changed
+      - live/**
+
+jobs:
+  update_staging_package:
+    # do not run in forks
+    if: github.repository_owner == 'openSUSE'
+
+    runs-on: ubuntu-latest
+
+    container:
+      image: registry.opensuse.org/opensuse/tumbleweed:latest
+
+    steps:
+      - name: Git Checkout
+        uses: actions/checkout@v4
+
+      - name: Configure and refresh repositories
+        # disable unused repositories to have a faster refresh
+        run: zypper modifyrepo -d repo-non-oss repo-openh264 repo-update && zypper ref
+
+      - name: Install tools
+        run: zypper --non-interactive install --no-recommends
+             make osc
+
+      - name: Configure osc
+        run: .github/workflows/configure_osc.sh
+        env:
+          OBS_USER:     ${{ secrets.OBS_USER }}
+          OBS_PASSWORD: ${{ secrets.OBS_PASSWORD }}
+
+      - name: Checkout agama-live
+        run: osc co -o dist systemsmanagement:Agama:Staging agama-live
+        working-directory: ./live
+
+      - name: Build sources
+        run: make clean && make
+        working-directory: ./live
+
+      - name: Update OBS files
+        run: osc addremove
+        working-directory: ./live/dist
+
+      - name: Check status
+        run: osc diff && osc status
+        working-directory: ./live/dist
+
+      - name: Commit agama-live
+        run:  osc commit -m "Updated to Agama $GITHUB_SHA"
+        working-directory: ./live/dist

PACKAGING.md

@@ -130,6 +130,7 @@ respect such a tag. (e.g. `2.1+42`).
 
 ### The Live ISO
 
-The ISO is built and developed in [systemsmanagement:Agama:Staging/agama-live](
-https://build.opensuse.org/package/show/systemsmanagement:Agama:Staging/agama-live).
-See [IMAGE.md](./IMAGE.md) for more details.
+The ISO is built in the [systemsmanagement:Agama:Staging/agama-live](
+https://build.opensuse.org/package/show/systemsmanagement:Agama:Staging/agama-live)
+OBS project. The sources are maintained in the [live](live) subdirectory. See
+[live/README.md](live/README.md) for more details.

doc/live_iso.md

@@ -2,6 +2,11 @@
 
 Agama installer is deployed as a regular application which can be installed and run on a local system. However, the most expected way of using Agama is by running it on a live ISO image.
 
+## Sources
+
+The Live ISO sources are maintained in the [live](../live/) subdirectory,
+See more details in a [live/README.md](../live/README.md) documentation.
+
 ## Live ISO Requirements
 
 A live ISO for running Agama should provide the following software:

live/.gitignore

@@ -0,0 +1 @@
+dist/

live/Makefile

@@ -0,0 +1,43 @@
+# Makefile for building the Live ISO sources for OBS, see README.md for more
+# details.
+
+# directory with the sources
+SRCDIR = ./src
+
+# the target directory
+DESTDIR = ./dist
+
+# the default build flavor, see the src/_multibuild file,
+# to build a different flavor run "make build FLAVOR=<flavor>"
+FLAVOR = openSUSE
+
+# files to copy from src/
+COPY_FILES = $(patsubst $(SRCDIR)/%,$(DESTDIR)/%,$(wildcard $(SRCDIR)/*))
+
+all: $(DESTDIR) $(COPY_FILES) $(DESTDIR)/config-cdroot.tar.xz $(DESTDIR)/root.tar.xz $(DESTDIR)/root-ALP-PXE.tar.xz
+
+# clean the destination directory (but keep the .osc directory if it is present)
+clean:
+	rm -rf $(DESTDIR)/*
+
+$(DESTDIR):
+	mkdir -p $@
+
+# copy the files from src/ to dist/
+$(DESTDIR)/%: $(SRCDIR)/%
+	cp -f $< $@
+
+# make a tarball from a directory
+# the tarball is reproducible, i.e. the same sources should result in the very
+# same tarball (bitwise) for the file time stamps use the date of the last
+# commit in the respective directory, use the UTC date to avoid possible time
+# zone and DST differences
+$(DESTDIR)/%.tar.xz: %
+	MTIME=$$(date --date="$$(git log -n 1 --pretty=format:%ci $<)" --utc +"%Y-%m-%d %H:%M:%S"); \
+	(cd $< && find . -xtype f -not -name README.md | LC_ALL=C sort | tar -c -v -f - --format=gnu --owner=0 --group=0 --files-from - --mtime="$$MTIME") | xz -c -9 -e > $@
+
+# build the ISO locally
+build: $(DESTDIR)
+	if [ ! -e  $(DESTDIR)/.osc ]; then make clean; osc co -o $(DESTDIR) systemsmanagement:Agama:Staging agama-live; fi
+	$(MAKE) all
+	(cd $(DESTDIR) && osc build -M $(FLAVOR) images)

live/PXE.md

@@ -0,0 +1,46 @@
+# Agama Network Installation (PXE)
+
+## Prerequisites
+
+The PXE boot infrastructure should already exist:
+
+- TFTP/DHCP running (usually dnsmasq)
+- FTP server running (usually vsftp)
+
+## Setup
+
+Extract the Linux kernel and the initrd from the archive:
+
+```shell
+osc getbinaries images x86_64 -M ALP-PXE
+tar -C /srv/ftp/image -xf \
+    binaries/agama-live.x86_64-5.0.0-ALP-PXE-Build4.1.install.tar
+
+cp /srv/ftp/image/pxeboot.agama-live.x86_64-5.0.0.initrd /srv/tftpboot/boot
+cp /srv/ftp/image/pxeboot.agama-live.x86_64-5.0.0.kernel /srv/tftpboot/boot
+```
+
+Update the PXE boot configuration in the `/srv/tftpboot/pxelinux.cfg/default`
+file:
+
+```
+default menu.c32
+prompt 0
+timeout 120
+
+menu title PXE Menu
+
+label live
+    menu label ^Agama
+    kernel /boot/pxeboot.agama-live.x86_64-5.0.0.kernel
+    append initrd=/boot/pxeboot.agama-live.x86_64-5.0.0.initrd rd.kiwi.install.pxe rd.kiwi.install.image=ftp://X.X.X.X/image/agama-live.x86_64-5.0.0.xz console=ttyS0,115200 rd.kiwi.ramdisk ramdisk_size=2097152
+```
+
+## Testing
+
+To test booting Agama in QEMU run these commands:
+
+```shell
+qemu-img create mydisk 20g
+qemu -boot n -m 4096 -hda mydisk
+```