Complete commenting for database methods
Change-Id: I4b7827c60ff7515440ebae421ecebf45054613aa
diff --git a/db/db.py b/db/db.py
index 2303a06..7c9fc75 100644
--- a/db/db.py
+++ b/db/db.py
@@ -106,7 +106,7 @@
# Constraints:
# Names and tags must be unique
# Tags must be in the range 1-4095 (802.1q spec)
- #
+ # Names can be any free-form text
def create_vlan(self, name, tag, is_base_vlan):
if int(tag) < 1 or int(tag) > 4095:
@@ -133,6 +133,7 @@
return vlan_id
+ # Internal helper function
def _delete_row(self, table, field, value):
try:
sql = "DELETE FROM %s WHERE %s = %s" % (table, field, '%s')
@@ -194,7 +195,8 @@
self._delete_row("vlan", "vlan_id", vlan_id)
return vlan_id
- # Grab one column from one row of a query on one column; useful as a quick wrapper
+ # Grab one column from one row of a query on one column; useful as
+ # a quick wrapper
def _get_element(self, select_field, table, compare_field, value):
# We really want to use psycopg's type handling deal with the
@@ -218,7 +220,8 @@
else:
return None
- # Grab one column from one row of a query on 2 columns; useful as a quick wrapper
+ # Grab one column from one row of a query on 2 columns; useful as
+ # a quick wrapper
def _get_element2(self, select_field, table, compare_field1, value1, compare_field2, value2):
# We really want to use psycopg's type handling deal with the
@@ -230,10 +233,6 @@
# keep it after python's own string substitution.
sql = "SELECT %s FROM %s WHERE %s = %s AND %s = %s" % (select_field, table, compare_field1, "%s", compare_field2, "%s")
- # Now, the next icky thing: we need to make sure that we're
- # passing a dict so that psycopg2 can pick it apart properly
- # for its own substitution code. We force this with the
- # trailing comma here
data = (value1, value2)
self.cursor.execute(sql, data)
@@ -242,7 +241,8 @@
else:
return None
- # Grab one column from multiple rows of a query; useful as a quick wrapper
+ # Grab one column from multiple rows of a query; useful as a quick
+ # wrapper
def _get_multi_elements(self, select_field, table, compare_field, value):
# We really want to use psycopg's type handling deal with the
@@ -269,50 +269,105 @@
else:
return None
+ # Simple lookup: look up a switch by ID, and return all the
+ # details of that switch.
+ #
+ # Returns None on failure.
def get_switch_by_id(self, switch_id):
return self._get_row("switch", "switch_id", switch_id)
+ # Simple lookup: look up a switch by name, and return the ID of
+ # that switch.
+ #
+ # Returns None on failure.
def get_switch_id_by_name(self, name):
return self._get_element("switch_id", "switch", "name", name)
+ # Simple lookup: look up a switch by ID, and return the name of
+ # that switch.
+ #
+ # Returns None on failure.
def get_switch_name_by_id(self, switch_id):
return self._get_element("name", "switch", "switch_id", switch_id)
+ # Simple lookup: look up a port by ID, and return all the details
+ # of that port.
+ #
+ # Returns None on failure.
def get_port_by_id(self, port_id):
return self._get_row("port", "port_id", port_id)
-
-
+ # Simple lookup: look up a switch by ID, and return the IDs of all
+ # the ports on that switch.
+ #
+ # Returns None on failure.
def get_ports_by_switch(self, switch_id):
return self._get_multi_elements("port_id", "port", "switch_id", switch_id)
+ # Simple lookup: look up a port by its name and its parent switch
+ # by ID, and return the ID of the port.
+ #
+ # Returns None on failure.
def get_port_by_switch_and_name(self, switch_id, name):
return self._get_element2("port_id", "port", "switch_id", switch_id, "name", name)
+ # Simple lookup: look up a port by ID, and return the current VLAN
+ # id of that port.
+ #
+ # Returns None on failure.
def get_current_vlan_id_by_port(self, port_id):
return self._get_element("current_vlan_id", "port", "port_id", port_id)
+ # Simple lookup: look up a port by ID, and return the base VLAN
+ # id of that port.
+ #
+ # Returns None on failure.
def get_base_vlan_id_by_port(self, port_id):
return self._get_element("base_vlan_id", "port", "port_id", port_id)
+ # Simple lookup: look up a current VLAN by ID, and return the IDs
+ # of all the ports on that VLAN.
+ #
+ # Returns None on failure.
def get_ports_by_current_vlan(self, vlan_id):
return self._get_multi_elements("port_id", "port", "current_vlan_id", vlan_id)
+ # Simple lookup: look up a base VLAN by ID, and return the IDs
+ # of all the ports on that VLAN.
+ #
+ # Returns None on failure.
def get_ports_by_base_vlan(self, vlan_id):
return self._get_multi_elements("port_id", "port", "base_vlan_id", vlan_id)
+ # Simple lookup: look up a VLAN by ID, and return all the details
+ # of that VLAN.
+ #
+ # Returns None on failure.
def get_vlan_by_id(self, vlan_id):
return self._get_row("vlan", "vlan_id", vlan_id)
+ # Simple lookup: look up a VLAN by name, and return the ID of that
+ # VLAN.
+ #
+ # Returns None on failure.
def get_vlan_id_by_name(self, name):
return self._get_element("vlan_id", "vlan", "name", name)
+ # Simple lookup: look up a VLAN by tag, and return the ID of that
+ # VLAN.
+ #
+ # Returns None on failure.
def get_vlan_id_by_tag(self, tag):
return self._get_element("vlan_id", "vlan", "tag", tag)
+ # Simple lookup: look up a VLAN by ID, and return the name of that
+ # VLAN.
+ #
+ # Returns None on failure.
def get_vlan_name_by_id(self, vlan_id):
return self._get_element("vlan_name", "vlan", "vlan_id", vlan_id)
+ # Grab one row of a query on one column; useful as a quick wrapper
def _get_row(self, table, field, value):
# We really want to use psycopg's type handling deal with the
@@ -374,6 +429,14 @@
raise
return port_id
+ # Set the current vlan of a port in the database. The VLAN is
+ # passed by ID.
+ #
+ # Constraints:
+ # 1. The port must already exist
+ # 2. The port must not be a trunk port
+ # 3. The port must not be locked
+ # 1. The VLAN must already exist in the database
def set_current_vlan(self, port_id, vlan_id):
port = self.get_port_by_id(port_id)
if port is None:
@@ -397,6 +460,14 @@
raise
return port_id
+ # Set the base vlan of a port in the database. The VLAN is
+ # passed by ID.
+ #
+ # Constraints:
+ # 1. The port must already exist
+ # 2. The port must not be a trunk port
+ # 3. The port must not be locked
+ # 1. The VLAN must already exist in the database
def set_base_vlan(self, port_id, vlan_id):
port = self.get_port_by_id(port_id)
if port is None:
@@ -422,6 +493,12 @@
raise
return port_id
+ # Return a port back to its base VLAN
+ #
+ # Constraints:
+ # 1. The port must already exist
+ # 2. The port must not be a trunk port
+ # 3. The port must not be locked
def restore_base_vlan(self, port_id):
port = self.get_port_by_id(port_id)
if port is None:
@@ -441,6 +518,7 @@
raise
return port_id
+ # Trivial helper function to return all the rows in a given table
def _dump_table(self, table):
result = []
self.cursor.execute("SELECT * FROM %s" % table)