#!/usr/bin/python
# Copyright 2015 Google Inc. All Rights Reserved.
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>

DOCUMENTATION = '''
---
module: kubernetes
version_added: "2.1"
short_description: Manage Kubernetes resources.
description:
    - This module can manage Kubernetes resources on an existing cluster using
      the Kubernetes server API. Users can specify in-line API data, or
      specify an existing Kubernetes YAML file. Currently, this module,
        Only supports HTTP Basic Auth
        Only supports 'strategic merge' for update, http://goo.gl/fCPYxT
        SSL certs are not working, use 'validate_certs=off' to disable
options:
  api_endpoint:
    description:
      - The IPv4 API endpoint of the Kubernetes cluster.
    required: true
    default: null
    aliases: ["endpoint"]
  inline_data:
    description:
      - The Kubernetes YAML data to send to the API I(endpoint). This option is
        mutually exclusive with C('file_reference').
    required: true
    default: null
  file_reference:
    description:
      - Specify full path to a Kubernets YAML file to send to API I(endpoint).
        This option is mutually exclusive with C('inline_data').
    required: false
    default: null
  certificate_authority_data:
    description:
      - Certificate Authority data for Kubernetes server. Should be in either
        standard PEM format or base64 encoded PEM data. Note that certificate
        verification is broken until ansible supports a version of
        'match_hostname' that can match the IP address against the CA data.
    required: false
    default: null
  state:
    description:
      - The desired action to take on the Kubernetes data.
    required: true
    default: "present"
    choices: ["present", "absent", "update", "replace"]
  password:
    description:
      - The HTTP Basic Auth password for the API I(endpoint). This should be set
        unless using the C('insecure') option.
    default: null
  username:
    description:
      - The HTTP Basic Auth username for the API I(endpoint). This should be set
        unless using the C('insecure') option.
    default: "admin"
  insecure:
    description:
      - "Reverts the connection to using HTTP instead of HTTPS. This option should
        only be used when execuing the M('kubernetes') module local to the Kubernetes
        cluster using the insecure local port (locahost:8080 by default)."
  validate_certs:
    description:
      - Enable/disable certificate validation. Note that this is set to
        C(false) until Ansible can support IP address based certificate
        hostname matching (exists in >= python3.5.0).
    required: false
    default: false

author: "Eric Johnson (@erjohnso) <erjohnso@google.com>"
'''

EXAMPLES = '''
# Create a new namespace with in-line YAML.
- name: Create a kubernetes namespace
  kubernetes:
    api_endpoint: 123.45.67.89
    username: admin
    password: redacted
    inline_data:
      kind: Namespace
      apiVersion: v1
      metadata:
        name: ansible-test
        labels:
          label_env: production
          label_ver: latest
        annotations:
          a1: value1
          a2: value2
    state: present

# Create a new namespace from a YAML file.
- name: Create a kubernetes namespace
  kubernetes:
    api_endpoint: 123.45.67.89
    username: admin
    password: redacted
    file_reference: /path/to/create_namespace.yaml
    state: present

# Do the same thing, but using the insecure localhost port
- name: Create a kubernetes namespace
  kubernetes:
    api_endpoint: 123.45.67.89
    insecure: true
    file_reference: /path/to/create_namespace.yaml
    state: present

'''

RETURN = '''
# Example response from creating a Kubernetes Namespace.
api_response:
    description: Raw response from Kubernetes API, content varies with API.
    returned: success
    type: dictionary
    contains:
        apiVersion: "v1"
        kind: "Namespace"
        metadata:
            creationTimestamp: "2016-01-04T21:16:32Z"
            name: "test-namespace"
            resourceVersion: "509635"
            selfLink: "/api/v1/namespaces/test-namespace"
            uid: "6dbd394e-b328-11e5-9a02-42010af0013a"
        spec:
            finalizers:
                - kubernetes
        status:
            phase: "Active"
'''

import yaml
import base64

############################################################################
############################################################################
# For API coverage, this Anislbe module provides capability to operate on
# all Kubernetes objects that support a "create" call (except for 'Events').
# In order to obtain a valid list of Kubernetes objects, the v1 spec file
# was referenced and the below python script was used to parse the JSON
# spec file, extract only the objects with a description starting with
# 'create a'. The script then iterates over all of these base objects
# to get the endpoint URL and was used to generate the KIND_URL map.
#
# import json
# from urllib2 import urlopen
#
# r = urlopen("https://raw.githubusercontent.com/kubernetes"
#            "/kubernetes/master/api/swagger-spec/v1.json")
# v1 = json.load(r)
#
# apis = {}
# for a in v1['apis']:
#     p = a['path']
#     for o in a['operations']:
#         if o["summary"].startswith("create a") and o["type"] != "v1.Event":
#             apis[o["type"]] = p
#
# def print_kind_url_map():
#     results = []
#     for a in apis.keys():
#         results.append('"%s": "%s"' % (a[3:].lower(), apis[a]))
#     results.sort()
#     print "KIND_URL = {"
#     print ",\n".join(results)
#     print "}"
#
# if __name__ == '__main__':
#     print_kind_url_map()
############################################################################
############################################################################

KIND_URL = {
    "binding": "/api/v1/namespaces/{namespace}/bindings",
    "endpoints": "/api/v1/namespaces/{namespace}/endpoints",
    "limitrange": "/api/v1/namespaces/{namespace}/limitranges",
    "namespace": "/api/v1/namespaces",
    "node": "/api/v1/nodes",
    "persistentvolume": "/api/v1/persistentvolumes",
    "persistentvolumeclaim": "/api/v1/namespaces/{namespace}/persistentvolumeclaims",  # NOQA
    "pod": "/api/v1/namespaces/{namespace}/pods",
    "podtemplate": "/api/v1/namespaces/{namespace}/podtemplates",
    "replicationcontroller": "/api/v1/namespaces/{namespace}/replicationcontrollers",  # NOQA
    "resourcequota": "/api/v1/namespaces/{namespace}/resourcequotas",
    "secret": "/api/v1/namespaces/{namespace}/secrets",
    "service": "/api/v1/namespaces/{namespace}/services",
    "serviceaccount": "/api/v1/namespaces/{namespace}/serviceaccounts"
}
USER_AGENT = "ansible-k8s-module/0.0.1"


# TODO(erjohnso): SSL Certificate validation is currently unsupported.
# It can be made to work when the following are true:
# - Ansible consistently uses a "match_hostname" that supports IP Address
#   matching. This is now true in >= python3.5.0. Currently, this feature
#   is not yet available in backports.ssl_match_hostname (still 3.4).
# - Ansible allows passing in the self-signed CA cert that is created with
#   a kubernetes master. The lib/ansible/module_utils/urls.py method,
#   SSLValidationHandler.get_ca_certs() needs a way for the Kubernetes
#   CA cert to be passed in and included in the generated bundle file.
# When this is fixed, the following changes can be made to this module,
# - Remove the 'return' statement in line 254 below
# - Set 'required=true' for certificate_authority_data and ensure that
#   ansible's SSLValidationHandler.get_ca_certs() can pick up this CA cert
# - Set 'required=true' for the validate_certs param.

def decode_cert_data(module):
    return
    d = module.params.get("certificate_authority_data")
    if d and not d.startswith("-----BEGIN"):
        module.params["certificate_authority_data"] = base64.b64decode(d)


def api_request(module, url, method="GET", headers=None, data=None):
    body = None
    if data:
        data = json.dumps(data)
    response, info = fetch_url(module, url, method=method, headers=headers, data=data)
    if int(info['status']) == -1:
        module.fail_json(msg="Failed to execute the API request: %s" % info['msg'], url=url, method=method, headers=headers)
    if response is not None:
        body = json.loads(response.read())
    return info, body


def k8s_create_resource(module, url, data):
    info, body = api_request(module, url, method="POST", data=data, headers={"Content-Type": "application/json"})
    if info['status'] == 409:
        name = data["metadata"].get("name", None)
        info, body = api_request(module, url + "/" + name)
        return False, body
    elif info['status'] >= 400:
        module.fail_json(msg="failed to create the resource: %s" % info['msg'], url=url)
    return True, body


def k8s_delete_resource(module, url, data):
    name = data.get('metadata', {}).get('name')
    if name is None:
        module.fail_json(msg="Missing a named resource in object metadata when trying to remove a resource")

    url = url + '/' + name
    info, body = api_request(module, url, method="DELETE")
    if info['status'] == 404:
        return False, "Resource name '%s' already absent" % name
    elif info['status'] >= 400:
        module.fail_json(msg="failed to delete the resource '%s': %s" % (name, info['msg']), url=url)
    return True, "Successfully deleted resource name '%s'" % name


def k8s_replace_resource(module, url, data):
    name = data.get('metadata', {}).get('name')
    if name is None:
        module.fail_json(msg="Missing a named resource in object metadata when trying to replace a resource")

    headers = {"Content-Type": "application/json"}
    url = url + '/' + name
    info, body = api_request(module, url, method="PUT", data=data, headers=headers)
    if info['status'] == 409:
        name = data["metadata"].get("name", None)
        info, body = api_request(module, url + "/" + name)
        return False, body
    elif info['status'] >= 400:
        module.fail_json(msg="failed to replace the resource '%s': %s" % (name, info['msg']), url=url)
    return True, body


def k8s_update_resource(module, url, data):
    name = data.get('metadata', {}).get('name')
    if name is None:
        module.fail_json(msg="Missing a named resource in object metadata when trying to update a resource")

    headers = {"Content-Type": "application/strategic-merge-patch+json"}
    url = url + '/' + name
    info, body = api_request(module, url, method="PATCH", data=data, headers=headers)
    if info['status'] == 409:
        name = data["metadata"].get("name", None)
        info, body = api_request(module, url + "/" + name)
        return False, body
    elif info['status'] >= 400:
        module.fail_json(msg="failed to update the resource '%s': %s" % (name, info['msg']), url=url)
    return True, body


def main():
    module = AnsibleModule(
        argument_spec=dict(
            http_agent=dict(default=USER_AGENT),

            username=dict(default="admin"),
            password=dict(default="", no_log=True),
            force_basic_auth=dict(default="yes"),
            validate_certs=dict(default=False, type='bool'),
            certificate_authority_data=dict(required=False),
            insecure=dict(default=False, type='bool'),
            api_endpoint=dict(required=True),
            file_reference=dict(required=False),
            inline_data=dict(required=False),
            state=dict(default="present", choices=["present", "absent", "update", "replace"])
        ),
        mutually_exclusive = (('file_reference', 'inline_data'), ('username', 'insecure'), ('password', 'insecure')),
        required_one_of = (('file_reference', 'inline_data'),),
    )

    decode_cert_data(module)

    api_endpoint = module.params.get('api_endpoint')
    state = module.params.get('state')
    insecure = module.params.get('insecure')
    inline_data = module.params.get('inline_data')
    file_reference = module.params.get('file_reference')

    if inline_data:
        data = inline_data
    else:
        try:
            f = open(file_reference, "r")
            data = [x for x in yaml.load_all(f)]
            f.close()
            if not data:
                module.fail_json(msg="No valid data could be found.")
        except:
            module.fail_json(msg="The file '%s' was not found or contained invalid YAML/JSON data" % file_reference)

    # set the transport type and build the target endpoint url
    transport = 'https'
    if insecure:
        transport = 'http'

    target_endpoint = "%s://%s" % (transport, api_endpoint)

    body = []
    changed = False

    # make sure the data is a list
    if not isinstance(data, list):
        data = [ data ]

    for item in data:
        namespace = "default"
        if item and 'metadata' in item:
            namespace = item.get('metadata', {}).get('namespace', "default")
            kind = item.get('kind', '').lower()
            try:
                url = target_endpoint + KIND_URL[kind]
            except KeyError:
                module.fail_json("invalid resource kind specified in the data: '%s'" % kind)
            url = url.replace("{namespace}", namespace)
        else:
            url = target_endpoint

        if state == 'present':
            item_changed, item_body = k8s_create_resource(module, url, item)
        elif state == 'absent':
            item_changed, item_body = k8s_delete_resource(module, url, item)
        elif state == 'replace':
            item_changed, item_body = k8s_replace_resource(module, url, item)
        elif state == 'update':
            item_changed, item_body = k8s_update_resource(module, url, item)

        changed |= item_changed
        body.append(item_body)

    module.exit_json(changed=changed, api_response=body)


# import module snippets
from ansible.module_utils.basic import *    # NOQA
from ansible.module_utils.urls import *     # NOQA


if __name__ == '__main__':
    main()