Merge pull request #3373 from exosite/devel

Added Linode inventory plugin

plugins/inventory/linode.ini

+# Ansible Linode external inventory script settings
+#
+
+[linode]
+
+# API calls to Linode are slow. For this reason, we cache the results of an API
+# call. Set this to the path you want cache files to be written to. Two files
+# will be written to this directory:
+#   - ansible-Linode.cache
+#   - ansible-Linode.index
+cache_path = /tmp
+
+# The number of seconds a cache file is considered valid. After this many
+# seconds, a new API call will be made, and the cache file will be updated.
+cache_max_age = 300

plugins/inventory/linode.py

+#!/usr/bin/env python
+
+'''
+Linode external inventory script
+=================================
+
+Generates inventory that Ansible can understand by making API request to
+AWS Linode using the Chube library.
+
+NOTE: This script assumes Ansible is being executed where Chube is already
+installed and has a valid config at ~/.chube. If not, run:
+
+    pip install chube
+    echo -e "---\napi_key: <YOUR API KEY GOES HERE>" > ~/.chube
+
+For more details, see: https://github.com/exosite/chube
+
+NOTE: This script also assumes that the Linodes in your account all have
+labels that correspond to hostnames that are in your resolver search path.
+Your resolver search path resides in /etc/hosts.
+
+When run against a specific host, this script returns the following variables:
+
+    - api_id
+    - datacenter_id
+    - datacenter_city (lowercase city name of data center, e.g. 'tokyo')
+    - label
+    - display_group
+    - create_dt
+    - total_hd
+    - total_xfer
+    - total_ram
+    - status
+    - public_ip (The first public IP found)
+    - private_ip (The first private IP found, or empty string if none)
+    - alert_cpu_enabled
+    - alert_cpu_threshold
+    - alert_diskio_enabled
+    - alert_diskio_threshold
+    - alert_bwin_enabled
+    - alert_bwin_threshold
+    - alert_bwout_enabled
+    - alert_bwout_threshold
+    - alert_bwquota_enabled
+    - alert_bwquota_threshold
+    - backup_weekly_daily
+    - backup_window
+    - watchdog
+
+Peter Sankauskas did most of the legwork here with his linode plugin; I
+just adapted that for Linode.
+'''
+
+# (c) 2013, Dan Slimmon
+#
+# 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/>.
+
+######################################################################
+
+# Standard imports
+import re
+import sys
+import argparse
+from time import time
+try:
+    import json
+except ImportError:
+    import simplejson as json
+
+# chube imports 'yaml', which is also the name of an inventory plugin,
+# so we remove the plugins dir from sys.path before importing it.
+old_path = sys.path
+sys.path = [d for d in sys.path if "ansible/plugins" not in d]
+from chube import *
+sys.path = old_path
+load_chube_config()
+
+# Imports for ansible
+import ConfigParser
+
+class LinodeInventory(object):
+    def __init__(self):
+        """Main execution path."""
+        # Inventory grouped by display group
+        self.inventory = {}
+        # Index of label to Linode ID
+        self.index = {}
+
+        # Read settings and parse CLI arguments
+        self.read_settings()
+        self.parse_cli_args()
+
+        # Cache
+        if self.args.refresh_cache:
+            self.do_api_calls_update_cache()
+        elif not self.is_cache_valid():
+            self.do_api_calls_update_cache()
+
+        # Data to print
+        if self.args.host:
+            data_to_print = self.get_host_info()
+        elif self.args.list:
+            # Display list of nodes for inventory
+            if len(self.inventory) == 0:
+                data_to_print = self.get_inventory_from_cache()
+            else:
+                data_to_print = self.json_format_dict(self.inventory, True)
+
+        print data_to_print
+
+    def is_cache_valid(self):
+        """Determines if the cache file has expired, or if it is still valid."""
+        if os.path.isfile(self.cache_path_cache):
+            mod_time = os.path.getmtime(self.cache_path_cache)
+            current_time = time()
+            if (mod_time + self.cache_max_age) > current_time:
+                if os.path.isfile(self.cache_path_index):
+                    return True
+        return False
+ 
+    def read_settings(self):
+        """Reads the settings from the .ini file."""
+        config = ConfigParser.SafeConfigParser()
+        config.read(os.path.dirname(os.path.realpath(__file__)) + '/linode.ini')
+
+        # Cache related
+        cache_path = config.get('linode', 'cache_path')
+        self.cache_path_cache = cache_path + "/ansible-linode.cache"
+        self.cache_path_index = cache_path + "/ansible-linode.index"
+        self.cache_max_age = config.getint('linode', 'cache_max_age')
+
+    def parse_cli_args(self):
+        """Command line argument processing"""
+        parser = argparse.ArgumentParser(description='Produce an Ansible Inventory file based on Linode')
+        parser.add_argument('--list', action='store_true', default=True,
+                           help='List nodes (default: True)')
+        parser.add_argument('--host', action='store',
+                           help='Get all the variables about a specific node')
+        parser.add_argument('--refresh-cache', action='store_true', default=False,
+                           help='Force refresh of cache by making API requests to Linode (default: False - use cache files)')
+        self.args = parser.parse_args()
+
+    def do_api_calls_update_cache(self):
+        """Do API calls, and save data in cache files."""
+        self.get_nodes()
+        self.write_to_cache(self.inventory, self.cache_path_cache)
+        self.write_to_cache(self.index, self.cache_path_index)
+
+    def get_nodes(self):
+        """Makes an Linode API call to get the list of nodes."""
+        try:
+            for node in Linode.search():
+                self.add_node(node)
+        except api.linode_api.ApiError, e:
+            print "Looks like Linode's API is down:"
+            print
+            print e
+            sys.exit(1)
+
+    def get_node(self, linode_id):
+        """Gets details about a specific node."""
+        try:
+            return Linode.find(api_id=linode_id)
+        except api.linode_api.ApiError, e:
+            print "Looks like Linode's API is down:"
+            print
+            print e
+            sys.exit(1)
+
+    def get_datacenter_city(self, node):
+        """Returns a the lowercase city name of the node's data center."""
+        location = node.datacenter.location
+        location = location.lower()
+        location = location.split(",")[0]
+        return location
+
+    def add_node(self, node):
+        """Adds an node to the inventory and index."""
+
+        # Only want running nodes
+        if not node.is_up():
+            return
+
+        dest = node.label
+
+        # Add to index
+        self.index[dest] = [node.api_id]
+
+        # Inventory: Group by node ID (always a group of 1)
+        self.inventory[node.api_id] = [dest]
+
+        # Inventory: Group by datacenter city
+        self.push(self.inventory, self.get_datacenter_city(node), dest)
+
+        # Inventory: Group by dipslay group
+        self.push(self.inventory, node.display_group, dest)
+
+    def get_host_info(self):
+        """Get variables about a specific host."""
+
+        if len(self.index) == 0:
+            # Need to load index from cache
+            self.load_index_from_cache()
+
+        if not self.args.host in self.index:
+            # try updating the cache
+            self.do_api_calls_update_cache()
+            if not self.args.host in self.index:
+                # host might not exist anymore
+                return self.json_format_dict({}, True)
+
+        node_id = self.index[self.args.host]
+
+        node = self.get_node(node_id)
+        node_vars = {}
+        for direct_attr in [
+            "api_id",
+            "datacenter_id",
+            "label",
+            "display_group",
+            "create_dt",
+            "total_hd",
+            "total_xfer",
+            "total_ram",
+            "status",
+            "alert_cpu_enabled",
+            "alert_cpu_threshold",
+            "alert_diskio_enabled",
+            "alert_diskio_threshold",
+            "alert_bwin_enabled",
+            "alert_bwin_threshold",
+            "alert_bwout_enabled",
+            "alert_bwout_threshold",
+            "alert_bwquota_enabled",
+            "alert_bwquota_threshold",
+            "backup_weekly_daily",
+            "backup_window",
+            "watchdog"
+        ]:
+            node_vars[direct_attr] = getattr(node, direct_attr)
+
+        node_vars["datacenter_city"] = self.get_datacenter_city(node)
+        node_vars["public_ip"] = [addr.address for addr in node.ipaddresses if addr.is_public][0]
+        node_vars["private_ip"] = [addr.address for addr in node.ipaddresses if not addr.is_public][0]
+
+        return self.json_format_dict(node_vars, True)
+
+    def push(self, my_dict, key, element):
+        """Pushed an element onto an array that may not have been defined in the dict."""
+        if key in my_dict:
+            my_dict[key].append(element);
+        else:
+            my_dict[key] = [element]
+
+    def get_inventory_from_cache(self):
+        """Reads the inventory from the cache file and returns it as a JSON object."""
+        cache = open(self.cache_path_cache, 'r')
+        json_inventory = cache.read()
+        return json_inventory
+
+    def load_index_from_cache(self):
+        """Reads the index from the cache file and sets self.index."""
+        cache = open(self.cache_path_index, 'r')
+        json_index = cache.read()
+        self.index = json.loads(json_index)
+
+    def write_to_cache(self, data, filename):
+        """Writes data in JSON format to a file."""
+        json_data = self.json_format_dict(data, True)
+        cache = open(filename, 'w')
+        cache.write(json_data)
+        cache.close()
+
+    def to_safe(self, word):
+        """Escapes any characters that would be invalid in an ansible group name."""
+        return re.sub("[^A-Za-z0-9\-]", "_", word)
+
+    def json_format_dict(self, data, pretty=False):
+        """Converts a dict to a JSON object and dumps it as a formatted string."""
+        if pretty:
+            return json.dumps(data, sort_keys=True, indent=2)
+        else:
+            return json.dumps(data)
+
+
+LinodeInventory()