fix serial datasource definition for nocloud

deprecate nocloud-net name

cloudinit/sources/DataSourceNoCloud.py

@@ -11,6 +11,7 @@
 import errno
 import logging
 import os
+from functools import partial
 
 from cloudinit import dmi, sources, util
 from cloudinit.net import eni
@@ -368,12 +369,39 @@ def __init__(self, sys_cfg, distro, paths):
         self.supported_seed_starts = ("http://", "https://")
 
     def ds_detect(self):
-        """NoCloud requires "nocloud-net" as the way to specify
-        seeding from an http(s) address. This diverges from all other
-        datasources in that it does a kernel commandline match on something
-        other than the datasource dsname for only DEP_NETWORK.
+        """Check dmi and kernel commandline for dsname
+
+        NoCloud historically used "nocloud-net" as its dsname
+        for network timeframe (DEP_NETWORK), which supports http(s) urls.
+        For backwards compatiblity, check for that dsname.
         """
-        return "nocloud-net" == sources.parse_cmdline()
+        log_deprecated = partial(
+            util.deprecate,
+            deprecated="The 'nocloud-net' datasource name",
+            deprecated_version="24.1",
+            extra_message=(
+                "Use 'nocloud' instead, which uses the seedfrom protocol"
+                "scheme (http// or file://) to decide how to run."
+            ),
+        )
+
+        if "nocloud-net" == sources.parse_cmdline():
+            log_deprecated()
+            return True
+
+        serial = sources.parse_cmdline_or_dmi(
+            dmi.read_dmi_data("system-serial-number") or "").lower()
+
+        if serial in (self.dsname.lower(), "nocloud-net"):
+            LOG.debug(
+                "Machine is configured by dmi serial number to run on "
+                "single datasource %s.",
+                self,
+            )
+            if serial == "nocloud-net":
+                log_deprecated()
+            return True
+        return False
 
 
 # Used to match classes to dependencies

cloudinit/sources/__init__.py

@@ -1195,10 +1195,13 @@ def parse_cmdline() -> str:
     """Check if command line argument for this datasource was passed
     Passing by command line overrides runtime datasource detection
     """
-    cmdline = util.get_cmdline()
-    ds_parse_0 = re.search(r"(?:^|\s)ds=([^\s;]+)", cmdline)
-    ds_parse_1 = re.search(r"(?:^|\s)ci\.ds=([^\s;]+)", cmdline)
-    ds_parse_2 = re.search(r"(?:^|\s)ci\.datasource=([^\s;]+)", cmdline)
+    return parse_cmdline_or_dmi(util.get_cmdline())
+
+
+def parse_cmdline_or_dmi(input: str) -> str:
+    ds_parse_0 = re.search(r"(?:^|\s)ds=([^\s;]+)", input)
+    ds_parse_1 = re.search(r"(?:^|\s)ci\.ds=([^\s;]+)", input)
+    ds_parse_2 = re.search(r"(?:^|\s)ci\.datasource=([^\s;]+)", input)
     ds = ds_parse_0 or ds_parse_1 or ds_parse_2
     deprecated = ds_parse_1 or ds_parse_2
     if deprecated: