Kubernetes connection support for mitogen.

ansible_mitogen/connection.py

@@ -125,6 +125,22 @@ def _connect_docker(spec):
     }
 
 
+def _connect_kubectl(spec):
+    """
+    Return ContextService arguments for a Kubernetes connection.
+    """
+    return {
+        'method': 'kubectl',
+        'kwargs': {
+            'username': spec['remote_user'],
+            'pod': spec['remote_addr'],
+            #'container': spec['container'],
+            'python_path': spec['python_path'],
+            'connect_timeout': spec['ansible_ssh_timeout'] or spec['timeout'],
+        }
+    }
+
+
 def _connect_jail(spec):
     """
     Return ContextService arguments for a FreeBSD jail connection.
@@ -187,6 +203,7 @@ def _connect_setns(spec):
             'python_path': spec['python_path'],
             'kind': spec['mitogen_kind'],
             'docker_path': spec['mitogen_docker_path'],
+            'kubectl_path': spec['mitogen_kubectl_path'],
             'lxc_info_path': spec['mitogen_lxc_info_path'],
             'machinectl_path': spec['mitogen_machinectl_path'],
         }
@@ -299,6 +316,7 @@ def _connect_mitogen_doas(spec):
 #: specification.
 CONNECTION_METHOD = {
     'docker': _connect_docker,
+    'kubectl': _connect_kubectl,
     'jail': _connect_jail,
     'local': _connect_local,
     'lxc': _connect_lxc,
@@ -366,6 +384,8 @@ def config_from_play_context(transport, inventory_name, connection):
             connection.get_task_var('mitogen_kind'),
         'mitogen_docker_path':
             connection.get_task_var('mitogen_docker_path'),
+        'mitogen_kubectl_path':
+            connection.get_task_var('mitogen_kubectl_path'),
         'mitogen_lxc_info_path':
             connection.get_task_var('mitogen_lxc_info_path'),
         'mitogen_machinectl_path':
@@ -398,6 +418,7 @@ def config_from_hostvars(transport, inventory_name, connection,
         'mitogen_via': hostvars.get('mitogen_via'),
         'mitogen_kind': hostvars.get('mitogen_kind'),
         'mitogen_docker_path': hostvars.get('mitogen_docker_path'),
+        'mitogen_kubectl_path': hostvars.get('mitogen_kubectl_path'),
         'mitogen_lxc_info_path': hostvars.get('mitogen_lxc_info_path'),
         'mitogen_machinectl_path': hostvars.get('mitogen_machinctl_path'),
     })

ansible_mitogen/plugins/connection/mitogen_kubectl.py

@@ -0,0 +1,45 @@
+# coding: utf-8
+# Copyright 2018, Yannig Perré
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+# may be used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+from __future__ import absolute_import
+import os.path
+import sys
+
+try:
+    import ansible_mitogen
+except ImportError:
+    base_dir = os.path.dirname(__file__)
+    sys.path.insert(0, os.path.abspath(os.path.join(base_dir, '../../..')))
+    del base_dir
+
+import ansible_mitogen.connection
+
+
+class Connection(ansible_mitogen.connection.Connection):
+    transport = 'kubectl'

ansible_mitogen/strategy.py

@@ -59,7 +59,7 @@ def wrap_connection_loader__get(name, *args, **kwargs):
     While the strategy is active, rewrite connection_loader.get() calls for
     some transports into requests for a compatible Mitogen transport.
     """
-    if name in ('docker', 'jail', 'local', 'lxc',
+    if name in ('docker', 'kubectl', 'jail', 'local', 'lxc',
                 'lxd', 'machinectl', 'setns', 'ssh'):
         name = 'mitogen_' + name
     return connection_loader__get(name, *args, **kwargs)

mitogen/core.py

@@ -717,6 +717,7 @@ class Importer(object):
             'debug',
             'doas',
             'docker',
+            'kubectl',
             'fakessh',
             'fork',
             'jail',

mitogen/kubectl.py

@@ -0,0 +1,78 @@
+# coding: utf-8
+# Copyright 2018, Yannig Perré
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+# may be used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+import logging
+
+import mitogen.core
+import mitogen.parent
+
+
+LOG = logging.getLogger(__name__)
+
+class Stream(mitogen.parent.Stream):
+    child_is_immediate_subprocess = True
+
+    pod = None
+    container = None
+    username = None
+    kubectl_path = 'kubectl'
+
+    # TODO: better way of capturing errors such as "No such container."
+    create_child_args = {
+        'merge_stdio': True
+    }
+
+    def construct(self, pod = None, container=None,
+                  kubectl_path=None, username=None,
+                  **kwargs):
+        assert pod
+        super(Stream, self).construct(**kwargs)
+        if pod:
+            self.pod = pod
+        if container:
+            self.container = container
+        if kubectl_path:
+            self.kubectl_path = kubectl_path
+        if username:
+            self.username = username
+
+    def connect(self):
+        super(Stream, self).connect()
+        self.name = u'kubectl.' + (self.pod) + str(self.container)
+
+    def get_boot_command(self):
+        args = ['exec', '-it', self.pod]
+        if self.username:
+            args += ['--username=' + self.username]
+
+        if self.container:
+            args += ['--container=' + self.container]
+        bits = [self.kubectl_path]
+
+        return bits + args + [ "--" ] + super(Stream, self).get_boot_command()

mitogen/parent.py

@@ -1596,6 +1596,9 @@ class Router(mitogen.core.Router):
     def docker(self, **kwargs):
         return self.connect(u'docker', **kwargs)
 
+    def kubectl(self, **kwargs):
+        return self.connect(u'kubectl', **kwargs)
+
     def fork(self, **kwargs):
         return self.connect(u'fork', **kwargs)
 

tests/ansible/test-kubectl.yml

@@ -0,0 +1,91 @@
+---
+
+- name: "Create pod"
+  tags: always
+  hosts: localhost
+  gather_facts: no
+  tasks:
+    - name: Create a test pod
+      k8s:
+        state: present
+        definition:
+          apiVersion: v1
+          kind: Pod
+          metadata:
+            name: test-pod-{{item}}
+            namespace: default
+          spec:
+            containers:
+            - name: python2
+              image: python:2
+              args: [ "sleep", "100000" ]
+      loop: "{{ range(10)|list }}"
+
+    - name: "Wait pod to be running"
+      debug: { msg: "pod is running" }
+      # status and availableReplicas might not be there. Using default value (d(default_value))
+      until: "pod_def.status.containerStatuses[0].ready"
+      # Waiting 100 s
+      retries: 50
+      delay: 2
+      vars:
+        pod_def: "{{lookup('k8s', kind='Pod', namespace='default', resource_name='test-pod-' ~ item)}}"
+      loop: "{{ range(10)|list }}"
+
+    - name: "Add pod to pods group"
+      add_host:
+        name: "test-pod-{{item}}"
+        groups: [ "pods" ]
+        ansible_connection: "kubectl"
+      changed_when: no
+      tags: "always"
+      loop: "{{ range(10)|list }}"
+
+- name: "Test kubectl connection (default strategy)"
+  tags: default
+  hosts: pods
+  strategy: "linear"
+  gather_facts: no
+  tasks:
+    - name: "Simple shell with linear"
+      shell: ls /tmp
+      loop: [ 1, 2, 3, 4, 5 ]
+
+    - name: "Simple file with linear"
+      file:
+        path: "/etc"
+        state: directory
+      loop: [ 1, 2, 3, 4, 5 ]
+
+- name: "Test kubectl connection (mitogen strategy)"
+  tags: mitogen
+  hosts: pods
+  strategy: "mitogen_linear"
+  gather_facts: no
+  tasks:
+    - name: "Simple shell with mitogen"
+      shell: ls /tmp
+      loop: [ 1, 2, 3, 4, 5 ]
+
+    - name: "Simple file with mitogen"
+      file:
+        path: "/etc"
+        state: directory
+      loop: [ 1, 2, 3, 4, 5 ]
+      register: _
+
+- name: "Destroy pod"
+  tags: cleanup
+  hosts: localhost
+  gather_facts: no
+  tasks:
+    - name: Destroy pod
+      k8s:
+        state: absent
+        definition:
+          apiVersion: v1
+          kind: Pod
+          metadata:
+            name: test-pod-{{item}}
+            namespace: default
+      loop: "{{ range(10)|list }}"