[Core] Error message improvement

src/azure-cli-core/azure/cli/core/_help.py

@@ -183,6 +183,26 @@ def show_help(self, cli_name, nouns, parser, is_group):
             if not nouns:
                 print(UX_SURVEY_PROMPT_COLOR if self.cli_ctx.enable_color else UX_SURVEY_PROMPT)
 
+    def get_examples(self, command, parser, is_group):
+        """Get examples of a certain command from the help file.
+        Get the text of the example, strip the newline character and
+        return a list of commands which start with the given command name.
+        """
+        nouns = command.split(' ')[1:]
+        self.update_loaders_with_help_file_contents(nouns)
+
+        delimiters = ' '.join(nouns)
+        help_file = self.command_help_cls(self, delimiters, parser) if not is_group \
+            else self.group_help_cls(self, delimiters, parser)
+        help_file.load(parser)
+
+        def strip_command(command):
+            command = command.replace('\\\n', '')
+            contents = [item for item in command.split(' ') if item]
+            return ' '.join(contents).strip()
+
+        return [strip_command(example.command) for example in help_file.examples]
+
     def _register_help_loaders(self):
         import azure.cli.core._help_loaders as help_loaders
         import inspect

src/azure-cli-core/azure/cli/core/azclierror.py

@@ -0,0 +1,88 @@
+# --------------------------------------------------------------------------------------------
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License. See License.txt in the project root for license information.
+# --------------------------------------------------------------------------------------------
+
+import sys
+from enum import Enum
+
+from knack.util import CLIError
+from knack.log import get_logger
+
+logger = get_logger(__name__)
+
+
+class AzCLIErrorType(Enum):
+    """ AzureCLI error types """
+
+    # userfaults
+    CommandNotFoundError = 'CommandNotFoundError'
+    ArgumentParseError = 'ArgumentParseError'
+    ValidationError = 'ValidationError'
+    ManualInterrupt = 'ManualInterrupt'
+    # service side error
+    ServiceError = 'ServiceError'
+    # client side error
+    ClientError = 'ClientError'
+    # unexpected error
+    UnexpectedError = 'UnexpectedError'
+
+
+class AzCLIError(CLIError):
+    """ AzureCLI error definition """
+
+    def __init__(self, error_type, error_msg, raw_exception=None, command=None):
+        """
+        :param error_type: The name of the AzureCLI error type.
+        :type error_type: azure.cli.core.util.AzCLIErrorType
+        :param error_msg: The error message detail.
+        :type error_msg: str
+        :param raw_exception: The raw exception.
+        :type raw_exception: Exception
+        :param command: The command which brings the error.
+        :type command: str
+        :param recommendations: The recommendations to resolve the error.
+        :type recommendations: list
+        """
+        self.error_type = error_type
+        self.error_msg = error_msg
+        self.raw_exception = raw_exception
+        self.command = command
+        self.recommendations = []
+        super().__init__(error_msg)
+
+    def set_recommendation(self, recommendation):
+        self.recommendations.append(recommendation)
+
+    def set_raw_exception(self, raw_exception):
+        self.raw_exception = raw_exception
+
+    def print_error(self):
+        from azure.cli.core.azlogging import CommandLoggerContext
+        with CommandLoggerContext(logger):
+            message = '{}: {}'.format(self.error_type.value, self.error_msg)
+            logger.error(message)
+            if self.raw_exception:
+                logger.exception(self.raw_exception)
+            if self.recommendations:
+                for recommendation in self.recommendations:
+                    print(recommendation, file=sys.stderr)
+
+    def send_telemetry(self):
+        import azure.cli.core.telemetry as telemetry
+        telemetry.set_error_type(self.error_type.value)
+
+        # For userfaults
+        if self.error_type in [AzCLIErrorType.CommandNotFoundError,
+                               AzCLIErrorType.ArgumentParseError,
+                               AzCLIErrorType.ValidationError,
+                               AzCLIErrorType.ManualInterrupt]:
+            telemetry.set_user_fault(self.error_msg)
+
+        # For failures: service side error, client side error, unexpected error
+        else:
+            telemetry.set_failure(self.error_msg)
+
+        # For unexpected error
+        if self.raw_exception:
+            telemetry.set_exception(self.raw_exception, '')

src/azure-cli-core/azure/cli/core/cloud.py

@@ -20,8 +20,11 @@
 
 CLOUD_CONFIG_FILE = os.path.join(GLOBAL_CONFIG_DIR, 'clouds.config')
 
-# Add names of clouds that don't allow telemetry data collection here such as JEDI.
-CLOUDS_FORBIDDING_TELEMETRY = []
+# Add names of clouds that don't allow telemetry data collection here such as some air-gapped clouds.
+CLOUDS_FORBIDDING_TELEMETRY = ['USSec', 'USNat']
+
+# Add names of clouds that don't allow Aladdin requests for command recommendations here
+CLOUDS_FORBIDDING_ALADDIN_REQUEST = ['USSec', 'USNat']
 
 
 class CloudNotRegisteredException(Exception):