cf99ff0165
>> Changed project name from plasma to valence in docs. >> Fixed docstring indentation. >> Added features docs. >> Added driver docs. >> Hidden licence headers from html files. Depends-On: Ia02bc00ad168b3c3d01ef6ca9696d43996091070 Change-Id: I1fa382d566165f5e76c84ad864024c0f546ef74c
95 lines
2.5 KiB
ReStructuredText
95 lines
2.5 KiB
ReStructuredText
..
|
|
Copyright 2016 Intel Corporation
|
|
All Rights Reserved.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License"); you may
|
|
not use this file except in compliance with the License. You may obtain
|
|
a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|
WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|
License for the specific language governing permissions and limitations
|
|
under the License.
|
|
|
|
.. _valence_db_development:
|
|
|
|
==============
|
|
DB Development
|
|
==============
|
|
|
|
Valence uses Etcd as the management DB for handling multiple pod managers,
|
|
as well as underneath hardware resources info.
|
|
There is one root Etcd directory for the pod managers, named
|
|
"/pod_managers".
|
|
Each key-value pair under directory "/pod_managers" indicates
|
|
information about one pod manager.
|
|
|
|
.. NOTE::
|
|
All db layer codes are located in valence/db.
|
|
|
|
|
|
Add a model for db
|
|
------------------
|
|
|
|
Models are defined in the valence/db/models.py file. A new model
|
|
should be updated there.
|
|
|
|
To add an example model for Etcd db, we should create
|
|
a class that inherits the ModelBase class in valence/db/models.py.
|
|
|
|
.. NOTE::
|
|
If timestamp info is needed for this model,
|
|
please inherit ModelBaseWithTimestamp class instead.
|
|
i.e.
|
|
|
|
.. code-block:: python
|
|
|
|
# valence/db/models.py
|
|
|
|
class ExampleModel(ModelBase):
|
|
|
|
# This is the Etcd dir the new model lives in
|
|
path = "example_model"
|
|
|
|
# The fields will be wrapped as a value for one object
|
|
fields = {
|
|
'uuid': {
|
|
'validate': types.Text.validate
|
|
},
|
|
'name': {
|
|
'validate': types.Text.validate
|
|
},
|
|
|
|
}
|
|
|
|
|
|
Add a driver for model
|
|
----------------------
|
|
|
|
Etcd driver definition is in the file valence/db/etcd_driver.py.
|
|
|
|
Considering adding operations for one example model,
|
|
we should create a class in valence/db/etcd_driver.py.
|
|
i.e.
|
|
|
|
.. code-block:: python
|
|
|
|
# valence/db/etcd_driver.py
|
|
|
|
@six.add_metaclass(singleton.Singleton)
|
|
class ExampleDriver(object):
|
|
|
|
def __init__(self, host=config.etcd_host, port=config.etcd_port):
|
|
self.client = etcd.Client(host=host, port=port)
|
|
|
|
def get_example_object(self, object_id):
|
|
pass
|
|
|
|
def create_example_object(self, values):
|
|
pass
|
|
|
|
There should be more guides to be continued later.
|