WIP answerfile generation

This process has several steps:
- building of a data structure holding all of the answerfile data,
  from a customizable base in data.py and from tests-specific items
- serialization as XML to be read by host-installer
- necessary changes to the ISO for host-installer to use it

This is needed so:
- different tests can use different parameters without the need for
  provisionning every answerfile to be used
- tests can dynamically add contents for their own needs, before the
  XML gets actualy written

FIXME:
- this covers boot from remastered ISO and not PXE, install on UEFI/NVMe disk (xml needs generation there too) and not BIOS/ATA (needs clever parametrization)
- doc

Author: ydirson

conftest.py

@@ -256,10 +256,42 @@ def sr_disk_for_all_hosts(request, host):
         logging.info(f">> Disk or block device {disk} is present and free on all pool members")
     yield candidates[0]
 
-@pytest.fixture(scope='session')
-def iso_remaster():
+@pytest.fixture(scope='function')
+def answerfile(request):
+    markers = request.node.get_closest_marker("answerfile")
+
+    if markers is None:
+        yield None              # no answerfile to generate
+        return
+
+    # construct answerfile definition from option "base", and explicit bits
+    marker = markers.args[0]
+    if marker["base"]:
+        from data import BASE_ANSWERFILES
+        answerfile_def = BASE_ANSWERFILES[marker["base"]]
+        del marker["base"]
+    else:
+        answerfile_def = {}
+    answerfile_def.update(marker)
+
+    # convert to a ElementTree.Element tree suitable for further
+    # modification before we serialize it to XML
+    import xml.etree.ElementTree as ET
+    root = ET.Element(answerfile_def["mode"])
+    del answerfile_def["mode"]
+    for name, defn in answerfile_def.items():
+        text = defn.get("text", None)
+        if text:
+            del defn["text"]
+        element = ET.SubElement(root, name, **defn)
+        if text:
+            element.text = text
+
+    yield ET.ElementTree(root)
+
+@pytest.fixture(scope='function')
+def iso_remaster(answerfile):
     SOURCE_ISO = "/home/user/iso/xcp-ng-8.2.1-20231130.iso" # FIXME dict in data.py
-    ANSWERFILE_URL = "http://pxe/configs/custom/ydi/install-8.2-uefi-iso-ext.xml" # FIXME
 
     from data import ISOSR_SRV, ISOSR_PATH, TEST_SSH_PUBKEY, TOOLS
     assert "iso-remaster" in TOOLS
@@ -270,6 +302,13 @@ def iso_remaster():
         remastered_iso = os.path.join(isotmp, "image.iso")
         iso_patcher_script = os.path.join(isotmp, "iso-patcher")
         img_patcher_script = os.path.join(isotmp, "img-patcher")
+        answerfile_xml = os.path.join(isotmp, "answerfile.xml")
+
+        if answerfile:
+            logging.info("generating answerfile %s", answerfile_xml)
+            answerfile.write(answerfile_xml)
+        else:
+            logging.info("no answerfile")
 
         logging.info("Remastering %s to %s", SOURCE_ISO, remastered_iso)
 
@@ -282,7 +321,8 @@ def iso_remaster():
 mkdir -p "$INSTALLIMG/root/.ssh"
 echo "{TEST_SSH_PUBKEY}" > "$INSTALLIMG/root/.ssh/authorized_keys"
 
-curl {ANSWERFILE_URL} -o "$INSTALLIMG/root/answerfile.xml"
+test ! -e "{answerfile_xml}" ||
+    cp "{answerfile_xml}" "$INSTALLIMG/root/answerfile.xml"
 """,
                   file=patcher_fd)
             os.chmod(patcher_fd.fileno(), 0o755)
@@ -293,8 +333,9 @@ def iso_remaster():
             print(f"""#!/bin/bash
 set -ex
 ISODIR="$1"
-SED_COMMANDS=(-e "s@/vmlinuz@/vmlinuz sshpassword={passwd} atexit=shell@")
-SED_COMMANDS+=(-e "s@/vmlinuz@/vmlinuz install answerfile=file:///root/answerfile.xml network_device=all@")
+SED_COMMANDS=(-e "s@/vmlinuz@/vmlinuz sshpassword={passwd} atexit=shell network_device=all@")
+test ! -e "{answerfile_xml}" ||
+    SED_COMMANDS+=(-e "s@/vmlinuz@/vmlinuz install answerfile=file:///root/answerfile.xml@")
 
 sed -i "${{SED_COMMANDS[@]}}" \
     "$ISODIR"/*/*/grub*.cfg \

data.py-dist

@@ -5,6 +5,7 @@
 # You need to have an SSH key into the hosts' /root/.ssh/authorized_keys.
 HOST_DEFAULT_USER = "root"
 HOST_DEFAULT_PASSWORD = ""
+HOST_DEFAULT_PASSWORD_HASH = "" # FIXME
 
 # Public key for a private key available to the test runner
 TEST_SSH_PUBKEY = "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDKz9uQOoxq6Q0SQ0XTzQHhDolvuo/7EyrDZsYQbRELhcPJG8MT/o5u3HyJFhIP2+HqBSXXgmqRPJUkwz9wUwb2sUwf44qZm/pyPUWOoxyVtrDXzokU/uiaNKUMhbnfaXMz6Ogovtjua63qld2+ZRXnIgrVtYKtYBeu/qKGVSnf4FTOUKl1w3uKkr59IUwwAO8ay3wVnxXIHI/iJgq6JBgQNHbn3C/SpYU++nqL9G7dMyqGD36QPFuqH/cayL8TjNZ67TgAzsPX8OvmRSqjrv3KFbeSlpS/R4enHkSemhgfc8Z2f49tE7qxWZ6x4Uyp5E6ur37FsRf/tEtKIUJGMRXN XCP-ng CI"
@@ -109,3 +110,13 @@ DEFAULT_LVMOISCSI_DEVICE_CONFIG = {
 #    'targetIQN': 'target.example',
 #    'SCSIid': 'id'
 }
+
+BASE_ANSWERFILES = dict(
+    INSTALL={
+        "mode": "installation",
+        "root-password": {"type": "hash", "text": HOST_DEFAULT_PASSWORD_HASH},
+        "admin-interface": {"name": "eth0", "proto": "dhcp"},
+        "timezone": {"text": "Europe/Paris"},
+        "keymap": {"text": "us"},
+    },
+)

pytest.ini

@@ -21,6 +21,9 @@ markers =
     # * VM-related markers to give parameters to fixtures
     vm_definitions: dicts of VM defs for create_vms fixture.
 
+    # * FIXME
+    answerfile: def of an answerfile
+
     # * Test targets related to VMs
     small_vm: tests that it is enough to run just once, using the smallest possible VM.
     big_vm: tests that it would be good to run with a big VM.

tests/install/test_install.py

@@ -24,6 +24,12 @@ class TestInstallNested:
              vdis=[dict(name="vm 1 system disk", size="100GiB", device="xvda", userdevice="0")],
              vifs=[dict(index=0, network_uuid="eabc1038-e40f-2ae5-0781-a3adbec1cae8")], # FIXME
              ))
+    @pytest.mark.answerfile(
+        {
+            "base": "INSTALL",
+            "source": {"type": "local"},
+            "primary-disk": {"text": "nvme0n1"},
+        })
     def test_install_nested_821_uefi(self, iso_remaster, create_vms):
         assert len(create_vms) == 1
         host_vm = create_vms[0]