Azure · williexu · Jul 3, 2018 · Jun 4, 2018 · Jun 4, 2018 · Jun 4, 2018
diff --git a/README.md b/README.md
@@ -101,6 +101,13 @@ Usage of /:  39.6% of 1.94GB   Swap usage:   0%   Users logged in: 0
 jasonsha@MyVM:~$
 ```
 
+#### Exit Codes
+For scripting purposes, we output certain exit codes for differing scenarios.
+`0`: Command ran successfully.
+`1`: Generic error; server returned bad status code, CLI validation failed, etc.
+`2`: Parser error; check input to command line.
+`3`: Missing ARM resource; used for existence check from `show` commands.
+
 #### More Samples and Snippets
 For more usage examples, take a look at our [GitHub samples repo](http://github.com/Azure/azure-cli-samples) or [https://docs.microsoft.com/en-us/cli/azure/overview](https://docs.microsoft.com/en-us/cli/azure/overview).
 

@@ -79,9 +79,9 @@ e.g. `keyvault create` instead of `keyvault vault create` (where `keyvault` only
 The following are standard names and behavioral descriptions for CRUD commands commonly found within the CLI. These standard command types MUST be followed for consistency with the rest of the CLI.
 
 - `CREATE` - standard command to create a new resource. Usually backed server-side by a PUT request. 'create' commands should be idempotent and should return the resource that was created.
-- `UPDATE` - command to selectively update properties of a resource and preserve existing values. May be backed server-side by either a PUT or PATCH request, but the behavior of the command should always be PATCH-like. All `update` commands should be registered using the `generic_update_command` helper to expose the three generic update properties. `update` commands MAY also allow for create-like behavior (PUTCH) in cases where a dedicated `create` command is deemed unnecessary. `update` commands should return the updated resource.
+- `UPDATE` - command to selectively update properties of a resource and preserve existing values. May be backed server-side by either a PUT or PATCH request, but the behavior of the command should always be PATCH-like. All `update` commands should be registered using the `generic_update_command` helper to expose the three generic update properties. `update` commands MAY also allow for create-like behavior (PATCH) in cases where a dedicated `create` command is deemed unnecessary. `update` commands should return the updated resource.
 - `SET` - command to replace all properties of a resource without preserving existing values, typically backed server-side by a PUT request. This is used when PATCH-like behavior is deemed unnecessary and means that any properties not specifies are reset to their default values. `set` commands are more rare compared to `update` commands. `set` commands should return the updated resource.
-- `SHOW` - command to show the properties of a resource, backed server-side by a GET request. Note, please ensure `404(Not Found)` is always trapped by using `exception_handler=empty_on_404` or catching the exception in your custom code. For context, refer to [issue](https://github.com/Azure/azure-cli/issues/6324).
+- `SHOW` - command to show the properties of a resource, backed server-side by a GET request. All `show` commands should be registered using the `generic_show_command` helper to ensure `404(Not Found)` is always returning an exit code of 3.
 - `LIST` - command to list instances of a resource, backed server-side by a GET request. When there are multiple "list-type" commands within an SDK to list resources at different levels (for example, listing resources in a subscription vice in a resource group) the functionality should be exposed by have a single list command with arguments to control the behavior. For example, if `--resource-group` is provided, the command will call `list_by_resource_group`; otherwise, it will call `list_by_subscription`.
 - `DELETE` - command to delete a resource, backed server-side by a DELETE request. Delete commands return nothing on success.
 

@@ -34,7 +34,7 @@ Release History
 
 2.0.35
 ++++++
-* Minor fixes
+* Added method of registering `show` commands to fail with exit code of 3.
 
 2.0.34
 ++++++

@@ -875,7 +875,7 @@ def generic_update_command(self, name,
             **merged_kwargs)
 
     def generic_wait_command(self, name, getter_name='get', getter_type=None, **kwargs):
-        from azure.cli.core.commands.arm import _cli_generic_update_command, _cli_generic_wait_command
+        from azure.cli.core.commands.arm import _cli_generic_wait_command
         self._check_stale()
         merged_kwargs = _merge_kwargs(kwargs, self.group_kwargs, CLI_COMMAND_KWARGS)
         # don't inherit deprecation info from command group
@@ -889,3 +889,16 @@ def generic_wait_command(self, name, getter_name='get', getter_type=None, **kwar
             '{} {}'.format(self.group_name, name),
             getter_op=getter_op,
             **merged_kwargs)
+
+    def generic_show_command(self, name, getter_name='get', getter_type=None, **kwargs):
+        from azure.cli.core.commands.arm import _cli_generic_show_command
+        self._check_stale()
+        merged_kwargs = _merge_kwargs(kwargs, self.group_kwargs, CLI_COMMAND_KWARGS)
+        if getter_type:
+            merged_kwargs = _merge_kwargs(getter_type.settings, merged_kwargs, CLI_COMMAND_KWARGS)
+        getter_op = self._resolve_operation(merged_kwargs, getter_name, getter_type)
+        _cli_generic_show_command(
+            self.command_loader,
+            '{} {}'.format(self.group_name, name),
+            getter_op=getter_op,
+            **merged_kwargs)
@@ -24,6 +24,7 @@
 logger = get_logger(__name__)
 
 
+# pylint:disable=too-many-lines
 class ArmTemplateBuilder(object):
 
     def __init__(self):
@@ -339,6 +340,14 @@ def _get_client_factory(_, kwargs):
     return factory
 
 
+def get_arguments_loader(context, getter_op, cmd_args=None):
+    getter_args = dict(extract_args_from_signature(context.get_op_handler(getter_op), excluded_params=EXCLUDED_PARAMS))
+    cmd_args = cmd_args or {}
+    cmd_args.update(getter_args)
+    cmd_args['cmd'] = CLICommandArgument('cmd', arg_type=ignore_type)
+    return cmd_args
+
+
 # pylint: disable=too-many-statements
 def _cli_generic_update_command(context, name, getter_op, setter_op, setter_arg_name='parameters',
                                 child_collection_prop_name=None, child_collection_key='name',
@@ -353,9 +362,6 @@ def _cli_generic_update_command(context, name, getter_op, setter_op, setter_arg_
         raise TypeError("Custom function operation must be a string. Got '{}'".format(
             custom_function_op))
 
-    def get_arguments_loader():
-        return dict(extract_args_from_signature(context.get_op_handler(getter_op), excluded_params=EXCLUDED_PARAMS))
-
     def set_arguments_loader():
         return dict(extract_args_from_signature(context.get_op_handler(setter_op), excluded_params=EXCLUDED_PARAMS))
 
@@ -368,10 +374,8 @@ def function_arguments_loader():
         return dict(extract_args_from_signature(custom_op, excluded_params=EXCLUDED_PARAMS))
 
     def generic_update_arguments_loader():
-
-        arguments = {}
+        arguments = get_arguments_loader(context, getter_op)
         arguments.update(set_arguments_loader())
-        arguments.update(get_arguments_loader())
         arguments.update(function_arguments_loader())
         arguments.pop('instance', None)  # inherited from custom_function(instance, ...)
         arguments.pop('parent', None)
@@ -406,7 +410,6 @@ def __call__(self, parser, namespace, values, option_string=None):
             help='Remove a property or an element from a list.  Example: {}'.format(remove_usage),
             metavar='LIST INDEX', arg_group=group_name
         )
-        arguments['cmd'] = CLICommandArgument('cmd', arg_type=ignore_type)
         return [(k, v) for k, v in arguments.items()]
 
     def _extract_handler_and_args(args, commmand_kwargs, op):
@@ -527,10 +530,7 @@ def _cli_generic_wait_command(context, name, getter_op, **kwargs):
     factory = _get_client_factory(name, kwargs)
 
     def generic_wait_arguments_loader():
-
-        getter_args = dict(extract_args_from_signature(context.get_op_handler(getter_op),
-                                                       excluded_params=EXCLUDED_PARAMS))
-        cmd_args = getter_args.copy()
+        cmd_args = get_arguments_loader(context, getter_op)
 
         group_name = 'Wait Condition'
         cmd_args['timeout'] = CLICommandArgument(
@@ -563,7 +563,6 @@ def generic_wait_arguments_loader():
                  "provisioningState!='InProgress', "
                  "instanceView.statuses[?code=='PowerState/running']"
         )
-        cmd_args['cmd'] = CLICommandArgument('cmd', arg_type=ignore_type)
         return [(k, v) for k, v in cmd_args.items()]
 
     def get_provisioning_state(instance):
@@ -646,6 +645,44 @@ def handler(args):
     context._cli_command(name, handler=handler, argument_loader=generic_wait_arguments_loader, **kwargs)  # pylint: disable=protected-access
 
 
+def _cli_generic_show_command(context, name, getter_op, **kwargs):
+
+    if not isinstance(getter_op, string_types):
+        raise ValueError("Getter operation must be a string. Got '{}'".format(type(getter_op)))
+
+    factory = _get_client_factory(name, kwargs)
+
+    def generic_show_arguments_loader():
+        cmd_args = get_arguments_loader(context, getter_op)
+        return [(k, v) for k, v in cmd_args.items()]
+
+    def handler(args):
+        from azure.cli.core.commands.client_factory import resolve_client_arg_name
+
+        cmd = args.get('cmd')
+        operations_tmpl = _get_operations_tmpl(cmd)
+        getter_args = dict(extract_args_from_signature(context.get_op_handler(getter_op),
+                                                       excluded_params=EXCLUDED_PARAMS))
+        client_arg_name = resolve_client_arg_name(operations_tmpl, kwargs)
+        try:
+            client = factory(context.cli_ctx) if factory else None
+        except TypeError:
+            client = factory(context.cli_ctx, args) if factory else None
+        if client and (client_arg_name in getter_args or client_arg_name == 'self'):
+            args[client_arg_name] = client
+
+        getter = context.get_op_handler(getter_op)
+        try:
+            return getter(**args)
+        except Exception as ex:  # pylint: disable=broad-except
+            if getattr(ex, 'status_code', None) == 404:
+                logger.error(getattr(ex, 'message', ex))
+                import sys
+                sys.exit(3)
+            raise
+    context._cli_command(name, handler=handler, argument_loader=generic_show_arguments_loader, **kwargs)  # pylint: disable=protected-access
+
+
 def verify_property(instance, condition):
     from jmespath import compile as compile_jmespath
     result = todict(instance)

diff --git a/src/command_modules/azure-cli-storage/azure/cli/command_modules/storage/commands.py b/src/command_modules/azure-cli-storage/azure/cli/command_modules/storage/commands.py
@@ -44,7 +44,7 @@ def get_custom_sdk(custom_module, client_factory, resource_type=ResourceType.DAT
         g.command('check-name', 'check_name_availability')
         g.custom_command('create', 'create_storage_account', min_api='2016-01-01')
         g.command('delete', 'delete', confirmation=True)
-        g.command('show', 'get_properties', exception_handler=g.get_handler_suppress_404())
+        g.generic_show_command('show', 'get_properties')
         g.custom_command('list', 'list_storage_accounts')
         g.custom_command('show-usage', 'show_storage_account_usage')
         g.custom_command('show-connection-string', 'show_storage_account_connection_string')
-Original file line number
+Diff line change
@@ Expand Up / @@ -34,7 +34,7 @@ Release History @@
 .0.35
     ++++++
-    * Minor fixes
+    * Added method of registering `show` commands to fail with exit code of 3.
 .0.34
     ++++++
@@ Expand Down @@