distros-info: add script to extract useful info from distros-info.yml

Passing a version number of NetworkManager to this new script, it prints
what distros are using that NM version and generates a new content for
.gitlab-ci/config.yml.

Automatically generating the config.yml content is useful because we can
easily update what distros we test in the CI and the Tier that they
belong, depending on what version of NM do they ship and whether they
have reached EOL or not.

Important: when generating a config.yml for an stable branch, not for
main, it must be generated from main. This is because we are not going
to keep distros-info.yml up to date in all branches, only in main.

.gitlab-ci/distros_support.py

@@ -0,0 +1,180 @@
+#!/usr/bin/env python3
+
+import datetime
+import os
+import sys
+
+try:
+    import yaml
+except ImportError:
+    print("Error: missing pyyaml. Install with `pip install pyyaml`.", file=sys.stderr)
+    quit(code=1)
+
+
+# These are the distros that we currently check, ordered by priority to be chosen as Tier 1
+ci_distros = ("fedora", "centos", "debian", "ubuntu", "alpine")
+
+
+def _parse_date(date_str) -> datetime.date:
+    return datetime.datetime.strptime(date_str, "%Y-%m-%d").date()
+
+
+def _is_supported(val_str, today) -> bool:
+    val_str = val_str.lower()
+    if val_str in ("yes", "true"):
+        return True
+    elif val_str in ("no", "false"):
+        return False
+    else:
+        support_date = _parse_date(val_str)
+        return today <= support_date
+
+
+def _nm_version_is_newer(nm_ver, nm_ver_from):
+    if nm_ver == "main":
+        return nm_ver_from != "main"  # main is newer than anything except main itself
+    elif nm_ver_from == "main":
+        return False
+    nm_ver = nm_ver.split(".")
+    nm_ver_from = nm_ver_from.split(".")
+    if int(nm_ver[0]) > int(nm_ver_from[0]):
+        return True
+    elif nm_ver[0] == nm_ver_from[0] and int(nm_ver[1]) > int(nm_ver_from[1]):
+        return True
+    return False
+
+
+if len(sys.argv) != 2:
+    print(f"Usage: {sys.argv[0]} <nm_version>")
+    quit(code=1)
+
+nm_version = sys.argv[1]
+today = datetime.date.today()
+with open(os.path.dirname(__file__) + "/distros-info.yml") as f:
+    distros_info = yaml.load(f, Loader=yaml.BaseLoader)
+
+# Warn about EOL'd distros to remove them
+for distro, versions in distros_info.items():
+    for info in versions:
+        if _is_supported(info["support"], today):
+            continue
+        if "extended-support" in info and _is_supported(
+            info["extended-support"], today
+        ):
+            continue
+        print(
+            f"Warn: {distro} {info['version']} reached EOL, consider deleting this entry",
+            file=sys.stderr,
+        )
+
+# Print distros that uses this nm_version
+print(f"# List of distros using NM {nm_version}")
+print("---")
+for distro, versions in distros_info.items():
+    for info in versions:
+        if nm_version == info["nm"] and _is_supported(info["support"], today):
+            try:
+                support_end_date = _parse_date(info["support"])
+                print(
+                    f"- {distro} {info['version']}, supported until {info['support']}"
+                )
+            except ValueError:
+                print(f"- {distro} {info['version']}, supported")
+
+# Collect info about what distros should be Tier 2 and 3
+tier2 = {}
+tier3 = {}
+for distro, versions in distros_info.items():
+    if distro not in ci_distros:
+        continue
+    for info in versions:
+        if not _is_supported(info["support"], today):
+            continue
+        if nm_version == info["nm"]:
+            tier2.setdefault(distro, []).append(info["version"])
+        elif _nm_version_is_newer(nm_version, info["nm"]):
+            tier3.setdefault(distro, []).append(info["version"])
+
+# Select a Tier1 distro
+tier1_distro, tier1_version = "", ""
+for distro in ci_distros:
+    for tier in (tier2, tier3):
+        if distro in tier:
+            # Exception: we want to use fedora:latest instead of fedora:rawhide because
+            # we don't want lot of build failures in Tier 1, which is run for every MR.
+            # We just ignore fedora:rawhide for Tier 1.
+            if distro == "fedora" and tier[distro][0] == "rawhide":
+                if len(tier[distro]) == 1:
+                    continue
+                idx = 1
+            else:
+                idx = 0
+
+            tier1_distro = distro
+            tier1_version = tier[distro].pop(idx)
+            if not tier[distro]:
+                del tier[distro]
+            break
+    if tier1_distro:
+        break
+
+if not tier1_distro or not tier1_version:
+    print("Warn: no suitable distro for Tier 1 found", file=sys.stderr)
+
+
+# Print the config.yml needed for the corresponding stable branch
+branch = "main" if nm_version == "main" else "nm-" + nm_version.replace(".", "-")
+print("\n# .gitlab-ci/config.yml for branch '{}'".format(branch))
+print(
+    """---
+# This file contains the configuration for the gitlab ci.
+#
+# To recreate the .gitlab-ci.yml file, run
+#   ci-fairy generate-template
+#
+# The ci-fairy tool is part of
+# https://gitlab.freedesktop.org/freedesktop/ci-templates
+#
+
+# Some distros are fairly similar, and we reuse similar scripts.
+# The base type maps the distro name to their base.
+base_types:
+  fedora: fedora
+  centos: fedora
+  debian: debian
+  ubuntu: debian
+  alpine: alpine
+
+# The list of all distributions we want to create job for.
+distributions:
+  # TIER 1: CI run for all MRs.
+  # The first tier:1 in the list is used to build the pages and check-{tree,patch}."""
+)
+print("  - name: {}".format(tier1_distro))
+print("    tier: 1")
+print("    versions:")
+print("      - '{}'".format(tier1_version))
+
+print(
+    """
+  # TIER 2: distribution versions that will or might use the current NM version.
+  # Run when doing a release."""
+)
+for distro, versions in tier2.items():
+    print("  - name: {}".format(distro))
+    print("    tier: 2")
+    print("    versions:")
+    for version in versions:
+        print("      - '{}'".format(version))
+
+print(
+    """
+  # TIER 3: distribution versions not in EOL but don't use the current NM version.
+  # Run when doing a release, but a failure won't be blocking for the release."""
+)
+for distro, versions in tier3.items():
+    print("  - name: {}".format(distro))
+    print("    tier: 3")
+    print("    versions:")
+    for version in versions:
+        print("      - '{}'".format(version))