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Files for Ansible for supporting dynamic host variables retrieved from a local SQLite database
#!/usr/bin/env bash
group_name="$1"
var_name="$2"
var_value="$3"
./create_dynamic_vars_db.py
sqlite3 dynamic_vars.db "INSERT OR REPLACE INTO group_vars ( group_name, var_name, var_value ) VALUES ( '${group_name}', '${var_name}', '${var_value}' );"
#!/usr/bin/env bash
host_name="$1"
var_name="$2"
var_value="$3"
./create_dynamic_vars_db.py
sqlite3 dynamic_vars.db "INSERT OR REPLACE INTO host_vars ( host_name, var_name, var_value ) VALUES ( '${host_name}', '${var_name}', '${var_value}' );"
#!/usr/bin/env python
'''
Create a SQLite database for storing dynamic group and host variable values.
'''
import sqlite3
conn = sqlite3.connect('dynamic_vars.db')
curs = conn.cursor()
# Create host variables table
curs.execute('''
CREATE TABLE IF NOT EXISTS host_vars (
host_name text,
var_name text,
var_value text,
CONSTRAINT pk_host_vars PRIMARY KEY ( host_name, var_name )
)''')
conn.commit()
# Create group variables table
curs.execute('''
CREATE TABLE IF NOT EXISTS group_vars (
group_name text,
var_name text,
var_value text,
CONSTRAINT pk_group_vars PRIMARY KEY ( group_name, var_name )
)''')
conn.commit()
conn.close()
#!/usr/bin/env python
'''
Custom dynamic inventory script that retrieves host variables from a SQLite database
Adapted from [Creating custom dynamic inventories for Ansible | Jeff Geerling](http://www.jeffgeerling.com/blog/creating-custom-dynamic-inventories-ansible)
'''
import os
import sys
import argparse
try:
import json
except ImportError:
import simplejson as json
import sqlite3
class Inventory(object):
def __init__(self):
self.inventory = {}
self.read_cli_args()
# Called with `--list`
if self.args.list:
self.populate_from_db()
# Called with `--host [hostname]`
elif self.args.host:
# Not implemented, since we return `_meta` key for `--list` call
self.inventory = self.empty_inventory()
# If no groups or vars are present, return an empty inventory.
else:
self.inventory = self.empty_inventory()
print json.dumps(self.inventory);
def populate_from_db(self):
conn = sqlite3.connect('dynamic_vars.db')
conn.row_factory = sqlite3.Row
curs = conn.cursor()
curs.execute('SELECT host_name, var_name, var_value FROM host_vars;')
vars_ = curs.fetchall()
for v in vars_:
self.add_host_var(v['host_name'], v['var_name'], v['var_value'])
conn.row_factory = sqlite3.Row
curs = conn.cursor()
curs.execute('SELECT group_name, var_name, var_value FROM group_vars;')
vars_ = curs.fetchall()
for v in vars_:
self.add_group_var(v['group_name'], v['var_name'], v['var_value'])
return self.inventory
# Example inventory for testing.
def example_inventory(self):
return { '_meta': { 'hostvars': {} } }
# Empty inventory for testing.
def empty_inventory(self):
return {'_meta': {'hostvars': {}}}
# Read the command line args passed to the script.
def read_cli_args(self):
parser = argparse.ArgumentParser()
parser.add_argument('--list', action = 'store_true')
parser.add_argument('--host', action = 'store')
self.args = parser.parse_args()
def add_host_var(self, host_name, var_name, var_value):
meta_dict = self.inventory.get( '_meta', {} )
hosts_dict = meta_dict.get( 'hostvars', {} )
host_vars = hosts_dict.get( host_name, {} )
host_vars[var_name] = var_value
hosts_dict[host_name] = host_vars
meta_dict = hosts_dict
self.inventory['_meta'] = meta_dict
def add_group_var(self, group_name, var_name, var_value):
group_dict = self.inventory.get( group_name, {} )
group_vars_dict = group_dict.get( 'vars', {} )
group_vars_dict[var_name] = var_value
group_dict['vars'] = group_vars_dict
self.inventory[group_name] = group_dict
# Get the inventory
Inventory()
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