Initial commit of change of semantics for module

The postgresql_user module has several drawbacks:
* No granularity for privileges
* PostgreSQL semantics force working on one
  database at time, at least for Tables. Which
  means that a single call can't remove all the 
  privileges for a user, and a user can't be
  removed until all the privileges are removed, 
  forcing a module failure with no way to 
  work around the issue.

Changes:
* Added the ability to specify granular privileges
  for database and tables within the database
* Report if user was removed, and add an option to 
  disable failing if user is not removed.
This commit is contained in:
Pepe Barbe 2012-08-21 11:20:16 -05:00
parent a32ae49bb6
commit 384839bfe1

View file

@ -34,35 +34,14 @@ def user_exists(cursor, user):
return cursor.rowcount > 0
def user_add(cursor, user, password, db):
def user_add(cursor, user, password):
"""Create a new user with write access to the database"""
query = "CREATE USER %(user)s with PASSWORD '%(password)s'"
cursor.execute(query % {"user": user, "password": password})
grant_privileges(cursor, user, db)
return True
def has_privileges(cursor, user, db):
"""Check if the user has create privileges on the database"""
query = "SELECT has_database_privilege(%(user)s, %(db)s, 'CREATE')"
cursor.execute(query, {'user': user, 'db': db})
return cursor.fetchone()[0]
def grant_privileges(cursor, user, db):
"""Grant all privileges on the database"""
query = "GRANT ALL PRIVILEGES ON DATABASE %(db)s TO %(user)s"
cursor.execute(query % {'user': user, 'db': db})
def revoke_privileges(cursor, user, db):
"""Revoke all privileges on the database"""
query = "REVOKE ALL PRIVILEGES ON DATABASE %(db)s FROM %(user)s"
cursor.execute(query % {'user': user, 'db': db})
def user_mod(cursor, user, password, db):
"""Update password and permissions"""
def user_chpass(cursor, user, password):
"""Change user password"""
changed = False
# Handle passwords.
@ -79,28 +58,131 @@ def user_mod(cursor, user, password, db):
if current_pass_hash != new_pass_hash:
changed = True
# Handle privileges.
# For now, we just check if the user has access to the database
if not has_privileges(cursor, user, db):
grant_privileges(cursor, user, db)
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
def user_delete(cursor, user, db):
"""Delete a user, first revoking privileges"""
revoke_privileges(cursor, user, db)
cursor.execute("DROP USER %(user)s" % {'user': user})
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 grant_table_privilege(cursor, user, table, priv):
if has_table_privilege(cursor, user, table, priv):
return False
query = 'GRANT %s ON TABLE %s TO %s' % (priv, table, user)
cursor.execute(query)
return True
def revoke_table_privilege(cursor, user, table, priv):
if not has_table_privilege(cursor, user, table, priv):
return False
query = 'REVOKE %s ON TABLE %s FROM %s' % (priv, table, user)
cursor.execute(query)
return True
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):
if has_database_privilege(cursor, user, db, priv):
return False
query = 'GRANT %s ON DATABASE %s TO %s' % (priv, db, user)
cursor.execute(query)
return True
def revoke_database_privilege(cursor, user, db, priv):
if not has_database_privilege(cursor, user, db, priv):
return False
query = 'REVOKE %s ON DATABASE %s FROM %s' % (priv, db, user)
cursor.execute(query)
return True
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_].iteritem():
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_].iteritem():
for privilege in privileges:
changed = grant_func(cursor, user, name, privilege)\
or changed
return changed
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
privs = {
'database':{},
'table':{}
}
for token in privs.split('/'):
if ':' not in token:
type_ = 'database'
name = db
privileges = token
else:
type_ = 'table'
name, privileges = token.split(':', 1)
privileges = privileges.split(',')
privs[type_][name] = privileges
return privs
# ===========================================
# Module execution.
#
def main():
module = AnsibleModule(
argument_spec=dict(
@ -110,13 +192,19 @@ def main():
user=dict(required=True, aliases=['name']),
password=dict(default=None),
state=dict(default="present", choices=["absent", "present"]),
db=dict(required=True),
priv=dict(default=None),
db=dict(default=''),
fail_on_user=dict(default=True)
)
)
user = module.params["user"]
password = module.params["password"]
state = module.params["state"]
fail_on_user = module.params["fail_on_user"]
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)
if not postgresqldb_found:
module.fail_json(msg="the python psycopg2 module is required")
@ -127,7 +215,8 @@ def main():
params_map = {
"login_host":"host",
"login_user":"user",
"login_password":"password"
"login_password":"password",
"db":"database"
}
kw = dict( (params_map[k], v) for (k, v) in module.params.iteritems()
if k in params_map and v != "" )
@ -137,23 +226,29 @@ def main():
except Exception, e:
module.fail_json(msg="unable to connect to database: %s" % e)
changed = False
if state == "present":
if user_exists(cursor, user):
changed = user_mod(cursor, user, password, db)
changed = user_chpass(cursor, user, password)
else:
if password is None:
msg = "password parameter required when adding a user"
module.fail_json(msg=msg)
changed = user_add(cursor, user, password, db)
elif state == "absent":
if user_exists(cursor, user):
changed = user_delete(cursor, user, db)
changed = user_add(cursor, user, password)
changed = grant_privileges(cursor, user, privs) or changed
else:
changed = False
# Commit the database changes
if user_exists(cursor, user):
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 = "unabel to remove user"
module.fail_json(msg=msg)
if changed:
db_connection.commit()
module.exit_json(changed=changed, user=user)
module.exit_json(changed=changed, user=user, user_removed=user_removed)
# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>