add fleet list credentials command

src/fleet/azext_fleet/_help.py

@@ -31,6 +31,15 @@
     short-summary: Delete an existing fleet.
 """
 
+helps['fleet credentials list'] = """
+    type: command
+    short-summary: List fleet kubeconfig credentials
+    parameters:
+    - name: --overwrite-existing
+      type: bool
+      short-summary: Overwrite any existing cluster entry with the same name.
+"""
+
 helps['fleet member'] = """
     type: group
     short-summary: Commands to manage a fleet member.

src/fleet/azext_fleet/_helpers.py

@@ -0,0 +1,135 @@
+import errno
+import os
+import platform
+import stat
+import tempfile
+import yaml
+
+from knack.log import get_logger
+from knack.prompting import NoTTYException, prompt_y_n
+from knack.util import CLIError
+from knack.log import get_logger
+
+logger = get_logger(__name__)
+
+def print_or_merge_credentials(path, kubeconfig, overwrite_existing, context_name):
+    """Merge an unencrypted kubeconfig into the file at the specified path, or print it to
+    stdout if the path is "-".
+    """
+    # Special case for printing to stdout
+    if path == "-":
+        print(kubeconfig)
+        return
+
+    # ensure that at least an empty ~/.kube/config exists
+    directory = os.path.dirname(path)
+    if directory and not os.path.exists(directory):
+        try:
+            os.makedirs(directory)
+        except OSError as ex:
+            if ex.errno != errno.EEXIST:
+                raise
+    if not os.path.exists(path):
+        with os.fdopen(os.open(path, os.O_CREAT | os.O_WRONLY, 0o600), 'wt'):
+            pass
+
+    # merge the new kubeconfig into the existing one
+    fd, temp_path = tempfile.mkstemp()
+    additional_file = os.fdopen(fd, 'w+t')
+    try:
+        additional_file.write(kubeconfig)
+        additional_file.flush()
+        _merge_kubernetes_configurations(
+            path, temp_path, overwrite_existing, context_name)
+    except yaml.YAMLError as ex:
+        logger.warning(
+            'Failed to merge credentials to kube config file: %s', ex)
+    finally:
+        additional_file.close()
+        os.remove(temp_path)
+
+def _merge_kubernetes_configurations(existing_file, addition_file, replace, context_name=None):
+    existing = _load_kubernetes_configuration(existing_file)
+    addition = _load_kubernetes_configuration(addition_file)
+
+    if context_name is not None:
+        addition['contexts'][0]['name'] = context_name
+        addition['contexts'][0]['context']['cluster'] = context_name
+        addition['clusters'][0]['name'] = context_name
+        addition['current-context'] = context_name
+
+    # rename the admin context so it doesn't overwrite the user context
+    for ctx in addition.get('contexts', []):
+        try:
+            if ctx['context']['user'].startswith('clusterAdmin'):
+                admin_name = ctx['name'] + '-admin'
+                addition['current-context'] = ctx['name'] = admin_name
+                break
+        except (KeyError, TypeError):
+            continue
+
+    if addition is None:
+        raise CLIError(
+            'failed to load additional configuration from {}'.format(addition_file))
+
+    if existing is None:
+        existing = addition
+    else:
+        _handle_merge(existing, addition, 'clusters', replace)
+        _handle_merge(existing, addition, 'users', replace)
+        _handle_merge(existing, addition, 'contexts', replace)
+        existing['current-context'] = addition['current-context']
+
+    # check that ~/.kube/config is only read- and writable by its owner
+    if platform.system() != "Windows" and not os.path.islink(existing_file):
+        existing_file_perms = "{:o}".format(stat.S_IMODE(os.lstat(existing_file).st_mode))
+        if not existing_file_perms.endswith("600"):
+            logger.warning(
+                '%s has permissions "%s".\nIt should be readable and writable only by its owner.',
+                existing_file,
+                existing_file_perms,
+            )
+
+    with open(existing_file, 'w+') as stream:
+        yaml.safe_dump(existing, stream, default_flow_style=False)
+
+    current_context = addition.get('current-context', 'UNKNOWN')
+    msg = 'Merged "{}" as current context in {}'.format(
+        current_context, existing_file)
+    print(msg)
+
+def _handle_merge(existing, addition, key, replace):
+    if not addition[key]:
+        return
+    if existing[key] is None:
+        existing[key] = addition[key]
+        return
+
+    for i in addition[key]:
+        for j in existing[key]:
+            if i['name'] == j['name']:
+                if replace or i == j:
+                    existing[key].remove(j)
+                else:
+                    msg = 'A different object named {} already exists in your kubeconfig file.\nOverwrite?'
+                    overwrite = False
+                    try:
+                        overwrite = prompt_y_n(msg.format(i['name']))
+                    except NoTTYException:
+                        pass
+                    if overwrite:
+                        existing[key].remove(j)
+                    else:
+                        msg = 'A different object named {} already exists in {} in your kubeconfig file.'
+                        raise CLIError(msg.format(i['name'], key))
+        existing[key].append(i)
+
+def _load_kubernetes_configuration(filename):
+    try:
+        with open(filename) as stream:
+            return yaml.safe_load(stream)
+    except (IOError, OSError) as ex:
+        if getattr(ex, 'errno', 0) == errno.ENOENT:
+            raise CLIError('{} does not exist'.format(filename))
+    except (yaml.parser.ParserError, UnicodeDecodeError) as ex:
+        raise CLIError('Error parsing {} ({})'.format(filename, str(ex)))

src/fleet/azext_fleet/_params.py

@@ -4,24 +4,31 @@
 # --------------------------------------------------------------------------------------------
 # pylint: disable=line-too-long
 
+import os
+from argcomplete.completers import FilesCompleter
 from azure.cli.core.commands.parameters import (
     get_resource_name_completion_list,
-    tags_type
+    tags_type,
+    file_type
 )
 from azext_fleet._validators import validate_member_cluster_id
 
 
 def load_arguments(self, _):
 
     with self.argument_context('fleet') as c:
-        c.argument('name', options_list=['--name', '-n'], help='Specify the fleet name.', completer=get_resource_name_completion_list('Microsoft.ContainerService/ManagedClusters'))
+        c.argument('name', options_list=['--name', '-n'], help='Specify the fleet name.')
 
     with self.argument_context('fleet create') as c:
         c.argument('tags', tags_type)
         c.argument('dns_name_prefix', options_list=['--dns-name-prefix', '-p'])
+
+    with self.argument_context('fleet credentials list') as c:
+        c.argument('context_name', options_list=['--context'], help='If specified, overwrite the default context name.')
+        c.argument('path', options_list=['--file', '-f'], type=file_type, completer=FilesCompleter(), default=os.path.join(os.path.expanduser('~'), '.kube', 'config'))
 
     with self.argument_context('fleet member') as c:
-        c.argument('member_name', help='Specify a member name. Default value is name of the managed cluster.')
+        c.argument('member_name', help='Specify a member name. Default value is name of the managed cluster.', completer=get_resource_name_completion_list('Microsoft.ContainerService/ManagedClusters'))
 
     with self.argument_context('fleet member join') as c:
         c.argument('member_cluster_id', validator=validate_member_cluster_id)

src/fleet/azext_fleet/commands.py

@@ -26,6 +26,7 @@ def load_command_table(self, _):
     with self.command_group("fleet", fleets_sdk, client_factory=cf_fleets) as g:
         g.custom_command("create", "create_fleet", supports_no_wait=True)
         g.custom_command("delete", "delete_fleet", supports_no_wait=True)
+        g.custom_command("credentials list", "list_credentials")
 
     # fleet members command group
     with self.command_group("fleet member", fleet_members_sdk, client_factory=cf_fleet_members) as g:

src/fleet/azext_fleet/custom.py

@@ -3,12 +3,16 @@
 # Licensed under the MIT License. See License.txt in the project root for license information.
 # --------------------------------------------------------------------------------------------
 
+import os
+
 from knack.log import get_logger
+from knack.util import CLIError
 
 from azure.cli.core.util import sdk_no_wait
 
 from azext_fleet._client_factory import CUSTOM_MGMT_FLEET
 from azext_fleet._resourcegroup import get_rg_location
+from azext_fleet._helpers import print_or_merge_credentials
 
 
 logger = get_logger(__name__)
@@ -56,14 +60,34 @@ def delete_fleet(cmd,  # pylint: disable=unused-argument
     return sdk_no_wait(no_wait, client.begin_delete, resource_group_name, name)
 
 
+def list_credentials(cmd,    # pylint: disable=unused-argument
+                     client,
+                     resource_group_name,
+                     name,
+                     path=os.path.join(os.path.expanduser(
+                         '~'), '.kube', 'config'),
+                     overwrite_existing=False,
+                     context_name=None):
+    credentialResults = client.list_credentials(resource_group_name, name)
+    if not credentialResults:
+        raise CLIError("No Kubernetes credentials found.")
+
+    try:
+        kubeconfig = credentialResults.kubeconfigs[0].value.decode(
+            encoding='UTF-8')
+        print_or_merge_credentials(
+            path, kubeconfig, overwrite_existing, context_name)
+    except (IndexError, ValueError):
+        raise CLIError("Fail to find kubeconfig file.")
+
+
 def join_fleet_member(cmd,
                       client,
                       resource_group_name,
                       name,
                       member_cluster_id,
                       member_name=None,
                       no_wait=False):
-    logger.info('in create fleetmember')
     FleetMember = cmd.get_models(
         "FleetMember",
         resource_type=CUSTOM_MGMT_FLEET,

src/fleet/azext_fleet/tests/latest/test_fleet_scenario.py

@@ -20,6 +20,8 @@ def test_fleet(self):
             self.check('name', '{name}')
         ])
 
+        self.cmd('fleet credentials list -g {rg} -n {name} --overwrite-existing')
+
         mc_id = self.cmd('aks create -g {rg} -n {member_name}', checks=[
             self.check('name', '{member_name}')
         ]).get_output_in_json()['id']