[RDBMS] az postgres flexible-server create: Set default sku to be coming from location capability API (#31141)

Co-authored-by: Matthew Boentoro <mboentoro@microsoft.com>

Author: mattboentoro

src/azure-cli/azure/cli/command_modules/rdbms/_breaking_change.py

@@ -602,7 +602,7 @@ def _flexible_server_params(command_group):
             # Add create mode as a parameter
             if command_group == 'postgres':
                 c.argument('tier', default='GeneralPurpose', arg_type=tier_arg_type)
-                c.argument('sku_name', default='Standard_D2s_v3', arg_type=sku_name_arg_type)
+                c.argument('sku_name', arg_type=sku_name_arg_type)
                 c.argument('storage_gb', default='128', arg_type=storage_gb_arg_type)
                 c.argument('version', default='17', arg_type=version_arg_type)
                 c.argument('backup_retention', default=7, arg_type=pg_backup_retention_arg_type)

src/azure-cli/azure/cli/command_modules/rdbms/_params.py

@@ -8,6 +8,7 @@
 import os
 import json
 from importlib import import_module
+from functools import cmp_to_key
 import re
 from urllib.parse import quote
 from urllib.request import urlretrieve
@@ -33,15 +34,16 @@
     cf_postgres_flexible_config, cf_postgres_flexible_admin
 from ._flexible_server_util import generate_missing_parameters, resolve_poller, \
     generate_password, parse_maintenance_window, get_current_time, build_identity_and_data_encryption, \
-    _is_resource_name, get_tenant_id, get_case_insensitive_key_value, get_enum_value_true_false
+    _is_resource_name, get_tenant_id, get_case_insensitive_key_value, get_enum_value_true_false, \
+    get_postgres_tiers, get_postgres_skus
 from ._flexible_server_location_capabilities_util import get_postgres_location_capability_info
 from ._util import get_index_tuning_settings_map
 from .flexible_server_custom_common import create_firewall_rule
 from .flexible_server_virtual_network import prepare_private_network, prepare_private_dns_zone, prepare_public_network
 from .validators import pg_arguments_validator, validate_server_name, validate_and_format_restore_point_in_time, \
     validate_postgres_replica, validate_georestore_network, pg_byok_validator, validate_migration_runtime_server, \
     validate_resource_group, check_resource_group, validate_citus_cluster, cluster_byok_validator, validate_backup_name, \
-    validate_virtual_endpoint_name_availability, validate_database_name
+    validate_virtual_endpoint_name_availability, validate_database_name, compare_sku_names
 
 logger = get_logger(__name__)
 DEFAULT_DB_NAME = 'flexibleserverdb'
@@ -85,6 +87,18 @@ def flexible_server_create(cmd, client,
 
     server_name = server_name.lower()
 
+    if sku_name is None:
+        # set sku_name from capability API
+        list_location_capability_info = get_postgres_location_capability_info(cmd, location)
+        tiers = [item.lower() for item in get_postgres_tiers(list_location_capability_info['sku_info'])]
+        try:
+            sku_info = list_location_capability_info['sku_info']
+            skus = list(get_postgres_skus(sku_info, tier.lower()))
+            skus = sorted(skus, key=cmp_to_key(compare_sku_names))
+            sku_name = skus[0]
+        except:
+            raise CLIError('Incorrect value for --tier. Allowed values : {}'.format(tiers))
+
     pg_arguments_validator(db_context,
                            server_name=server_name,
                            database_name=database_name,