sources/azure: report ready in local phase (#1265)

Pre-provisioned instances report ready early in the local phase and
again in the non-local phase, during setup().  Non-PPS only reports
ready during non-local phase.

Update the process to report ready during the local phase for all
cases.  Only attempt to do so if networking is up to prevent stalling
boot. We've already waited at least 20 minutes for DHCP if we're
provisioning, or 5 minutes for DHCP on normal boot requesting updated
network configuration.

- Extend _report_ready() with pubkey_info and raise exception
  on error to consolidate reporting done in _negotiate() and
  _report_ready().

- Remove setup(), moving relevant logic into crawl_metadata().

- Move remaining _negotiate() logic into _cleanup_markers() and
  _determine_wireserver_pubkey_info().

These changes effectively fix two issues that were present:

(1) _negotiated is incorrectly set to True

When failing to report ready.  _negotiate() squashed the exception and
the return value was not checked.  This was probably masked due to the
forced removal of obj.pkl on Ubuntu instances, but would be preferable
once we start persisting it to prevent unnecessary re-negotiation.

(2) provisioning media is not ejected for non-PPS

_negotiate() did not pass iso_dev parameter when reporting ready.  The
host will ensure this operation takes place, but it is preferable to
eject /dev/sr0 from within the guest when we're done with it.

Lastly, this removes any need for lease file parsing as the wireserver
addressed is tracked for ephemeral DHCP.  A follow-up PR will remove
this now-unused logic.

Signed-off-by: Chris Patterson <cpatterson@microsoft.com>

1 files changed, 54 insertions, 60 deletions

diff --git a/cloudinit/sources/DataSourceAzure.py b/cloudinit/sources/DataSourceAzure.py
index f8e1dd02..359dfbde 100755
--- a/cloudinit/sources/DataSourceAzure.py
+++ b/cloudinit/sources/DataSourceAzure.py
@@ -317,17 +317,16 @@ class DataSourceAzure(sources.DataSource):
             [util.get_cfg_by_path(sys_cfg, DS_CFG_PATH, {}), BUILTIN_DS_CONFIG]
         )
         self.dhclient_lease_file = self.ds_cfg.get("dhclient_lease_file")
+        self._iso_dev = None
         self._network_config = None
         self._ephemeral_dhcp_ctx = None
         self._wireserver_endpoint = DEFAULT_WIRESERVER_ENDPOINT
-        self.iso_dev = None
 
     def _unpickle(self, ci_pkl_version: int) -> None:
         super()._unpickle(ci_pkl_version)
 
         self._ephemeral_dhcp_ctx = None
-        if not hasattr(self, "iso_dev"):
-            self.iso_dev = None
+        self._iso_dev = None
         self._wireserver_endpoint = DEFAULT_WIRESERVER_ENDPOINT
 
     def __str__(self):
@@ -441,7 +440,6 @@ class DataSourceAzure(sources.DataSource):
         cfg = {}
         files = {}
 
-        iso_dev = None
         if os.path.isfile(REPROVISION_MARKER_FILE):
             metadata_source = "IMDS"
             report_diagnostic_event(
@@ -462,7 +460,7 @@ class DataSourceAzure(sources.DataSource):
                                 src, load_azure_ds_dir
                             )
                         # save the device for ejection later
-                        iso_dev = src
+                        self._iso_dev = src
                     else:
                         md, userdata_raw, cfg, files = load_azure_ds_dir(src)
                     ovf_is_accessible = True
@@ -497,7 +495,7 @@ class DataSourceAzure(sources.DataSource):
         # not have UDF support.  In either case, require IMDS metadata.
         # If we require IMDS metadata, try harder to obtain networking, waiting
         # for at least 20 minutes.  Otherwise only wait 5 minutes.
-        requires_imds_metadata = bool(iso_dev) or not ovf_is_accessible
+        requires_imds_metadata = bool(self._iso_dev) or not ovf_is_accessible
         timeout_minutes = 5 if requires_imds_metadata else 20
         try:
             self._setup_ephemeral_networking(timeout_minutes=timeout_minutes)
@@ -514,8 +512,6 @@ class DataSourceAzure(sources.DataSource):
             report_diagnostic_event(msg)
             raise sources.InvalidMetaDataException(msg)
 
-        self.iso_dev = iso_dev
-
         # Refresh PPS type using metadata.
         pps_type = self._determine_pps_type(cfg, imds_md)
         if pps_type != PPSType.NONE:
@@ -612,9 +608,23 @@ class DataSourceAzure(sources.DataSource):
             crawled_data["metadata"]["random_seed"] = seed
         crawled_data["metadata"]["instance-id"] = self._iid()
 
-        if pps_type != PPSType.NONE:
-            LOG.info("Reporting ready to Azure after getting ReprovisionData")
-            self._report_ready()
+        if self._negotiated is False and self._is_ephemeral_networking_up():
+            # Report ready and fetch public-keys from Wireserver, if required.
+            pubkey_info = self._determine_wireserver_pubkey_info(
+                cfg=cfg, imds_md=imds_md
+            )
+            try:
+                ssh_keys = self._report_ready(pubkey_info=pubkey_info)
+            except Exception:
+                # Failed to report ready, but continue with best effort.
+                pass
+            else:
+                LOG.debug("negotiating returned %s", ssh_keys)
+                if ssh_keys:
+                    crawled_data["metadata"]["public-keys"] = ssh_keys
+
+                self._cleanup_markers()
+                self._negotiated = True
 
         return crawled_data
 
@@ -844,24 +854,6 @@ class DataSourceAzure(sources.DataSource):
         return iid
 
     @azure_ds_telemetry_reporter
-    def setup(self, is_new_instance):
-        if self._negotiated is False:
-            LOG.debug(
-                "negotiating for %s (new_instance=%s)",
-                self.get_instance_id(),
-                is_new_instance,
-            )
-            ssh_keys = self._negotiate()
-            LOG.debug("negotiating returned %s", ssh_keys)
-            if ssh_keys:
-                self.metadata["public-keys"] = ssh_keys
-            self._negotiated = True
-        else:
-            LOG.debug(
-                "negotiating already done for %s", self.get_instance_id()
-            )
-
-    @azure_ds_telemetry_reporter
     def _wait_for_nic_detach(self, nl_sock):
         """Use the netlink socket provided to wait for nic detach event.
         NOTE: The function doesn't close the socket. The caller owns closing
@@ -983,11 +975,12 @@ class DataSourceAzure(sources.DataSource):
 
         :raises sources.InvalidMetaDataException: On error reporting ready.
         """
-        report_ready_succeeded = self._report_ready()
-        if not report_ready_succeeded:
+        try:
+            self._report_ready()
+        except Exception as error:
             msg = "Failed reporting ready while in the preprovisioning pool."
             report_diagnostic_event(msg, logger_func=LOG.error)
-            raise sources.InvalidMetaDataException(msg)
+            raise sources.InvalidMetaDataException(msg) from error
 
         self._create_report_ready_marker()
 
@@ -1400,25 +1393,36 @@ class DataSourceAzure(sources.DataSource):
 
         return False
 
-    def _report_ready(self) -> bool:
+    @azure_ds_telemetry_reporter
+    def _report_ready(
+        self, *, pubkey_info: Optional[List[str]] = None
+    ) -> Optional[List[str]]:
         """Tells the fabric provisioning has completed.
 
-        @return: The success status of sending the ready signal.
+        :param pubkey_info: Fingerprints of keys to request from Wireserver.
+
+        :raises Exception: if failed to report.
+
+        :returns: List of SSH keys, if requested.
         """
         try:
-            get_metadata_from_fabric(
+            data = get_metadata_from_fabric(
                 fallback_lease_file=None,
                 dhcp_opts=self._wireserver_endpoint,
-                iso_dev=self.iso_dev,
+                iso_dev=self._iso_dev,
+                pubkey_info=pubkey_info,
             )
-            return True
         except Exception as e:
             report_diagnostic_event(
                 "Error communicating with Azure fabric; You may experience "
                 "connectivity issues: %s" % e,
                 logger_func=LOG.warning,
             )
-            return False
+            raise
+
+        # Reporting ready ejected OVF media, no need to do so again.
+        self._iso_dev = None
+        return data
 
     def _ppstype_from_imds(self, imds_md: dict) -> Optional[str]:
         try:
@@ -1464,6 +1468,7 @@ class DataSourceAzure(sources.DataSource):
             "{pid}: {time}\n".format(pid=os.getpid(), time=time()),
         )
 
+    @azure_ds_telemetry_reporter
     def _reprovision(self):
         """Initiate the reprovisioning workflow.
 
@@ -1479,40 +1484,29 @@ class DataSourceAzure(sources.DataSource):
             return (md, ud, cfg, {"ovf-env.xml": contents})
 
     @azure_ds_telemetry_reporter
-    def _negotiate(self):
-        """Negotiate with fabric and return data from it.
+    def _determine_wireserver_pubkey_info(
+        self, *, cfg: dict, imds_md: dict
+    ) -> Optional[List[str]]:
+        """Determine the fingerprints we need to retrieve from Wireserver.
 
-        On success, returns a dictionary including 'public_keys'.
-        On failure, returns False.
+        :return: List of keys to request from Wireserver, if any, else None.
         """
-        pubkey_info = None
+        pubkey_info: Optional[List[str]] = None
         try:
-            self._get_public_keys_from_imds(self.metadata["imds"])
+            self._get_public_keys_from_imds(imds_md)
         except (KeyError, ValueError):
-            pubkey_info = self.cfg.get("_pubkeys", None)
+            pubkey_info = cfg.get("_pubkeys", None)
             log_msg = "Retrieved {} fingerprints from OVF".format(
                 len(pubkey_info) if pubkey_info is not None else 0
             )
             report_diagnostic_event(log_msg, logger_func=LOG.debug)
+        return pubkey_info
 
-        LOG.debug("negotiating with fabric")
-        try:
-            ssh_keys = get_metadata_from_fabric(
-                fallback_lease_file=self.dhclient_lease_file,
-                pubkey_info=pubkey_info,
-            )
-        except Exception as e:
-            report_diagnostic_event(
-                "Error communicating with Azure fabric; You may experience "
-                "connectivity issues: %s" % e,
-                logger_func=LOG.warning,
-            )
-            return False
-
+    def _cleanup_markers(self):
+        """Cleanup any marker files."""
         util.del_file(REPORTED_READY_MARKER_FILE)
         util.del_file(REPROVISION_MARKER_FILE)
         util.del_file(REPROVISION_NIC_DETACHED_MARKER_FILE)
-        return ssh_keys
 
     @azure_ds_telemetry_reporter
     def activate(self, cfg, is_new_instance):