ansible/library/postgresql_user
Bernhard Weitzhofer 8456cb8e52 postgresql_user: fix docstrings
Change documentation of "state" param to refer to user (role) state instead of
database state.

Change 2 function docstrings to reflect the code
2013-04-01 13:56:37 +02:00

461 lines
16 KiB
Python

#!/usr/bin/python
# -*- coding: utf-8 -*-
# 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: postgresql_user
short_description: Adds or removes a users (roles) from a PostgreSQL database.
description:
- Add or remove PostgreSQL users (roles) from a remote host and, optionally,
grant the users access to an existing database or tables.
- The fundamental function of the module is to create, or delete, roles from
a PostgreSQL cluster. Privilege assignment, or removal, is an optional
step, which works on one database at a time. This allows for the module to
be called several times in the same module to modify the permissions on
different databases, or to grant permissions to already existing users.
- A user cannot be removed until all the privileges have been stripped from
the user. In such situation, if the module tries to remove the user it
will fail. To avoid this from happening the fail_on_user option signals
the module to try to remove the user, but if not possible keep going; the
module will report if changes happened and separately if the user was
removed or not.
version_added: "0.6"
options:
name:
description:
- name of the user (role) to add or remove
required: true
default: null
password:
description:
- set the user's password
required: true
default: null
db:
description:
- name of database where permissions will be granted
required: false
default: null
fail_on_user:
description:
- if C(yes), fail when user can't be removed. Otherwise just log and continue
required: false
default: yes
choices: [ "yes", "no" ]
login_user:
description:
- User (role) used to authenticate with PostgreSQL
required: false
default: postgres
login_password:
description:
- Password used to authenticate with PostgreSQL
required: false
default: null
login_host:
description:
- Host running PostgreSQL.
required: false
default: localhost
priv:
description:
- "PostgreSQL privileges string in the format: C(table:priv1,priv2)"
required: false
default: null
role_attr_flags:
description:
- "PostgreSQL role attributes string in the format: CREATEDB,CREATEROLE,SUPERUSER"
required: false
default: null
choices: [ "[NO]SUPERUSER","[NO]CREATEROLE", "[NO]CREATEUSER", "[NO]CREATEDB",
"[NO]INHERIT", "[NO]LOGIN", "[NO]REPLICATION" ]
state:
description:
- The user (role) state
required: false
default: present
choices: [ "present", "absent" ]
examples:
- code: "postgresql_user: db=acme user=django password=ceec4eif7ya priv=CONNECT/products:ALL"
description: Create django user and grant access to database and products table
- code: "postgresql_user: user=rails password=secret role_attr_flags=CREATEDB,NOSUPERUSER"
description: Create rails user, grant privilege to create other databases and demote rails from super user status
- code: "postgresql_user: db=acme user=test priv=ALL/products:ALL state=absent fail_on_user=no"
description: Remove test user privileges from acme
- code: "postgresql_user: db=test user=test priv=ALL state=absent"
description: Remove test user from test database and the cluster
- code: INSERT,UPDATE/table:SELECT/anothertable:ALL
description: Example privileges string format
notes:
- The default authentication assumes that you are either logging in as or
sudo'ing to the postgres account on the host.
- This module uses psycopg2, a Python PostgreSQL database adapter. You must
ensure that psycopg2 is installed on the host before using this module. If
the remote host is the PostgreSQL server (which is the default case), then
PostgreSQL must also be installed on the remote host. For Ubuntu-based
systems, install the postgresql, libpq-dev, and python-psycopg2 packages
on the remote host before using this module.
- If you specify PUBLIC as the user, then the privilege changes will apply
to all users. You may not specify password or role_attr_flags when the
PUBLIC user is specified.
requirements: [ psycopg2 ]
author: Lorin Hochstein
'''
import re
try:
import psycopg2
except ImportError:
postgresqldb_found = False
else:
postgresqldb_found = True
# ===========================================
# PostgreSQL module specific support methods.
#
def user_exists(cursor, user):
# The PUBLIC user is a special case that is always there
if user == 'PUBLIC':
return True
query = "SELECT rolname FROM pg_roles WHERE rolname=%(user)s"
cursor.execute(query, {'user': user})
return cursor.rowcount > 0
def user_add(cursor, user, password, role_attr_flags):
"""Create a new database user (role)."""
query = "CREATE USER \"%(user)s\" with PASSWORD '%(password)s' %(role_attr_flags)s"
cursor.execute(query % {"user": user, "password": password, "role_attr_flags": role_attr_flags})
return True
def user_alter(cursor, user, password, role_attr_flags):
"""Change user password and/or attributes. Return True if changed, False otherwise."""
changed = False
if user == 'PUBLIC':
if password is not None:
module.fail_json(msg="cannot change the password for PUBLIC user")
elif role_attr_flags != '':
module.fail_json(msg="cannot change the role_attr_flags for PUBLIC user")
else:
return False
# Handle passwords.
if password is not None or role_attr_flags is not None:
# Select password and all flag-like columns in order to verify changes.
select = "SELECT * FROM pg_authid where rolname=%(user)s"
cursor.execute(select, {"user": user})
# Grab current role attributes.
current_role_attrs = cursor.fetchone()
if password is not None:
# Update the role attributes, including password.
alter = "ALTER USER \"%(user)s\" WITH PASSWORD '%(password)s' %(role_attr_flags)s"
cursor.execute(alter % {"user": user, "password": password, "role_attr_flags": role_attr_flags})
else:
# Update the role attributes, excluding password.
alter = "ALTER USER \"%(user)s\" WITH %(role_attr_flags)s"
cursor.execute(alter % {"user": user, "role_attr_flags": role_attr_flags})
# Grab new role attributes.
cursor.execute(select, {"user": user})
new_role_attrs = cursor.fetchone()
# Detect any differences between current_ and new_role_attrs.
for i in range(len(current_role_attrs)):
if current_role_attrs[i] != new_role_attrs[i]:
changed = True
return changed
def user_delete(cursor, user):
"""Try to remove a user. Returns True if successful otherwise False"""
cursor.execute("SAVEPOINT ansible_pgsql_user_delete")
try:
cursor.execute("DROP USER \"%s\"" % user)
except:
cursor.execute("ROLLBACK TO SAVEPOINT ansible_pgsql_user_delete")
cursor.execute("RELEASE SAVEPOINT ansible_pgsql_user_delete")
return False
cursor.execute("RELEASE SAVEPOINT ansible_pgsql_user_delete")
return True
def has_table_privilege(cursor, user, table, priv):
query = 'SELECT has_table_privilege(%s, %s, %s)'
cursor.execute(query, (user, table, priv))
return cursor.fetchone()[0]
def get_table_privileges(cursor, user, table):
if '.' in table:
schema, table = table.split('.', 1)
else:
schema = 'public'
query = '''SELECT privilege_type FROM information_schema.role_table_grants
WHERE grantee=%s AND table_name=%s AND table_schema=%s'''
cursor.execute(query, (user, table, schema))
return set([x[0] for x in cursor.fetchall()])
def grant_table_privilege(cursor, user, table, priv):
prev_priv = get_table_privileges(cursor, user, table)
query = 'GRANT %s ON TABLE \"%s\" TO \"%s\"' % (priv, table, user)
cursor.execute(query)
curr_priv = get_table_privileges(cursor, user, table)
return len(curr_priv) > len(prev_priv)
def revoke_table_privilege(cursor, user, table, priv):
prev_priv = get_table_privileges(cursor, user, table)
query = 'REVOKE %s ON TABLE \"%s\" FROM \"%s\"' % (priv, table, user)
cursor.execute(query)
curr_priv = get_table_privileges(cursor, user, table)
return len(curr_priv) < len(prev_priv)
def get_database_privileges(cursor, user, db):
priv_map = {
'C':'CREATE',
'T':'TEMPORARY',
'c':'CONNECT',
}
query = 'SELECT datacl FROM pg_database WHERE datname = %s'
cursor.execute(query, (db,))
datacl = cursor.fetchone()[0]
if datacl is None:
return []
r = re.search('%s=(C?T?c?)/[a-z]+\,?' % user, datacl)
if r is None:
return []
o = []
for v in r.group(1):
o.append(priv_map[v])
return o
def has_database_privilege(cursor, user, db, priv):
query = 'SELECT has_database_privilege(%s, %s, %s)'
cursor.execute(query, (user, db, priv))
return cursor.fetchone()[0]
def grant_database_privilege(cursor, user, db, priv):
prev_priv = get_database_privileges(cursor, user, db)
if user == "PUBLIC":
query = 'GRANT %s ON DATABASE \"%s\" TO PUBLIC' % (priv, db)
else:
query = 'GRANT %s ON DATABASE \"%s\" TO \"%s\"' % (priv, db, user)
cursor.execute(query)
curr_priv = get_database_privileges(cursor, user, db)
return len(curr_priv) > len(prev_priv)
def revoke_database_privilege(cursor, user, db, priv):
prev_priv = get_database_privileges(cursor, user, db)
if user == "PUBLIC":
query = 'REVOKE %s ON DATABASE \"%s\" FROM PUBLIC' % (priv, db)
else:
query = 'REVOKE %s ON DATABASE \"%s\" FROM \"%s\"' % (priv, db, user)
cursor.execute(query)
curr_priv = get_database_privileges(cursor, user, db)
return len(curr_priv) < len(prev_priv)
def revoke_privileges(cursor, user, privs):
if privs is None:
return False
changed = False
for type_ in privs:
revoke_func = {
'table':revoke_table_privilege,
'database':revoke_database_privilege
}[type_]
for name, privileges in privs[type_].iteritems():
for privilege in privileges:
changed = revoke_func(cursor, user, name, privilege)\
or changed
return changed
def grant_privileges(cursor, user, privs):
if privs is None:
return False
changed = False
for type_ in privs:
grant_func = {
'table':grant_table_privilege,
'database':grant_database_privilege
}[type_]
for name, privileges in privs[type_].iteritems():
for privilege in privileges:
changed = grant_func(cursor, user, name, privilege)\
or changed
return changed
def parse_role_attrs(role_attr_flags):
"""
Parse role attributes string for user creation.
Format:
attributes[,attributes,...]
Where:
attributes := CREATEDB,CREATEROLE,NOSUPERUSER,...
"""
if ',' not in role_attr_flags:
return role_attr_flags
flag_set = role_attr_flags.split(",")
o_flags = " ".join(flag_set)
return o_flags
def parse_privs(privs, db):
"""
Parse privilege string to determine permissions for database db.
Format:
privileges[/privileges/...]
Where:
privileges := DATABASE_PRIVILEGES[,DATABASE_PRIVILEGES,...] |
TABLE_NAME:TABLE_PRIVILEGES[,TABLE_PRIVILEGES,...]
"""
if privs is None:
return privs
o_privs = {
'database':{},
'table':{}
}
for token in privs.split('/'):
if ':' not in token:
type_ = 'database'
name = db
priv_set = set(x.strip() for x in token.split(','))
else:
type_ = 'table'
name, privileges = token.split(':', 1)
priv_set = set(x.strip() for x in privileges.split(','))
o_privs[type_][name] = priv_set
return o_privs
# ===========================================
# Module execution.
#
def main():
module = AnsibleModule(
argument_spec=dict(
login_user=dict(default="postgres"),
login_password=dict(default=""),
login_host=dict(default=""),
user=dict(required=True, aliases=['name']),
password=dict(default=None),
state=dict(default="present", choices=["absent", "present"]),
priv=dict(default=None),
db=dict(default=''),
port=dict(default='5432'),
fail_on_user=dict(default='yes'),
role_attr_flags=dict(default='')
),
supports_check_mode = True
)
user = module.params["user"]
password = module.params["password"]
state = module.params["state"]
fail_on_user = module.params["fail_on_user"] == 'yes'
db = module.params["db"]
if db == '' and module.params["priv"] is not None:
module.fail_json(msg="privileges require a database to be specified")
privs = parse_privs(module.params["priv"], db)
port = module.params["port"]
role_attr_flags = parse_role_attrs(module.params["role_attr_flags"])
if not postgresqldb_found:
module.fail_json(msg="the python psycopg2 module is required")
# To use defaults values, keyword arguments must be absent, so
# check which values are empty and don't include in the **kw
# dictionary
params_map = {
"login_host":"host",
"login_user":"user",
"login_password":"password",
"port":"port",
"db":"database"
}
kw = dict( (params_map[k], v) for (k, v) in module.params.iteritems()
if k in params_map and v != "" )
try:
db_connection = psycopg2.connect(**kw)
cursor = db_connection.cursor()
except Exception, e:
module.fail_json(msg="unable to connect to database: %s" % e)
kw = dict(user=user)
changed = False
user_removed = False
if state == "present":
if user_exists(cursor, user):
if module.check_mode:
kw['changed'] = True
module.exit_json(**kw)
changed = user_alter(cursor, user, password, role_attr_flags)
else:
if password is None:
msg = "password parameter required when adding a user"
module.fail_json(msg=msg)
if module.check_mode:
kw['changed'] = True
module.exit_json(**kw)
changed = user_add(cursor, user, password, role_attr_flags)
changed = grant_privileges(cursor, user, privs) or changed
else:
if user_exists(cursor, user):
if module.check_mode:
kw['changed'] = True
kw['user_removed'] = True
module.exit_json(**kw)
changed = revoke_privileges(cursor, user, privs)
user_removed = user_delete(cursor, user)
changed = changed or user_removed
if fail_on_user and not user_removed:
msg = "unable to remove user"
module.fail_json(msg=msg)
kw['user_removed'] = user_removed
if changed:
db_connection.commit()
kw['changed'] = changed
module.exit_json(**kw)
# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>
main()