From 3dbb84755b31229eb1de7bc8b56c637ca9dbcfd2 Mon Sep 17 00:00:00 2001
From: Nikolay Stanchev <ns17@it-innovation.soton.ac.uk>
Date: Fri, 22 Jun 2018 16:09:49 +0100
Subject: [PATCH] Implements database connectivity using PostgreSQL for the
CLMC service
---
src/service/clmcservice/__init__.py | 6 ++++
src/service/clmcservice/initialize_db.py | 38 ++++++++++++++++++++++++
src/service/clmcservice/models.py | 28 +++++++++++++++++
src/service/development.ini | 13 ++++++--
src/service/production.ini | 11 +++++--
src/service/setup.py | 6 ++++
6 files changed, 97 insertions(+), 5 deletions(-)
create mode 100644 src/service/clmcservice/initialize_db.py
create mode 100644 src/service/clmcservice/models.py
diff --git a/src/service/clmcservice/__init__.py b/src/service/clmcservice/__init__.py
index 3f29bc4..69ee81b 100644
--- a/src/service/clmcservice/__init__.py
+++ b/src/service/clmcservice/__init__.py
@@ -23,6 +23,8 @@
"""
from pyramid.config import Configurator
+from sqlalchemy import engine_from_config
+from clmcservice.models import DBSession, Base
from clmcservice.aggregationapi.utilities import validate_conf_file, RUNNING_FLAG, MALFORMED_FLAG, CONF_FILE_ATTRIBUTE, CONF_OBJECT, AGGREGATOR_CONFIG_SECTION
@@ -31,6 +33,10 @@ def main(global_config, **settings):
This function returns a Pyramid WSGI application.
"""
+ engine = engine_from_config(settings, 'sqlalchemy.') # initialise a database engine by using the 'sqlalchemy' setting in the configuration .ini file
+ DBSession.configure(bind=engine) # bind the engine to a DB session
+ Base.metadata.bind = engine # bind the engine to the Base class metadata
+
# validate and use (if valid) the configuration file
conf_file_path = settings[CONF_FILE_ATTRIBUTE]
conf = validate_conf_file(conf_file_path) # if None returned here, service is in unconfigured state
diff --git a/src/service/clmcservice/initialize_db.py b/src/service/clmcservice/initialize_db.py
new file mode 100644
index 0000000..a0b1a09
--- /dev/null
+++ b/src/service/clmcservice/initialize_db.py
@@ -0,0 +1,38 @@
+import os
+import sys
+from sqlalchemy import engine_from_config
+from pyramid.paster import get_appsettings, setup_logging
+from clmcservice.models import DBSession, Base
+
+
+def usage(argv):
+ """
+ A method to be called when the script has been used in an incorrect way.
+
+ :param argv: cmd arguments
+ """
+
+ cmd = os.path.basename(argv[0])
+ print('usage: %s <config_uri>\n'
+ '(example: "%s development.ini")' % (cmd, cmd))
+ sys.exit(1)
+
+
+def main(argv=sys.argv):
+ """
+ Main method of the script - initialises the database by creating all tables declared in the models.py module
+
+ :param argv: command line arguments - expects a configuration .ini file from which it retrieves the URL with which to connect to postgresql
+ """
+
+ if len(argv) != 2:
+ usage(argv) # in case of wrong usage
+
+ config_uri = argv[1]
+ setup_logging(config_uri)
+
+ settings = get_appsettings(config_uri) # get application specific settings
+ engine = engine_from_config(settings, 'sqlalchemy.') # create the db engine from the sqlalchemy setting configured in the .ini file
+
+ DBSession.configure(bind=engine)
+ Base.metadata.create_all(engine) # creates all model tables
diff --git a/src/service/clmcservice/models.py b/src/service/clmcservice/models.py
new file mode 100644
index 0000000..840fc08
--- /dev/null
+++ b/src/service/clmcservice/models.py
@@ -0,0 +1,28 @@
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import scoped_session, sessionmaker
+from zope.sqlalchemy import ZopeTransactionExtension
+from sqlalchemy import Column, String, Integer, UniqueConstraint
+
+
+DBSession = scoped_session(sessionmaker(extension=ZopeTransactionExtension())) # initialise a ORM session, ought to be reused across the different modules
+Base = declarative_base() # initialise a declarative Base instance to use for the web app models
+
+
+class ServiceFunctionEndpoint(Base):
+ """
+ This class defines the main model of the WHOAMI API, declaring the global tags for a specific service function on a specific endpoint.
+ """
+
+ __tablename__ = 'sfendpoints' # table name in the PostgreSQL database
+
+ __table_args__ = (UniqueConstraint('sf_i', 'sf_endpoint', 'sr'),) # defines a unique constraint across 3 columns - sf_i, sf_endpoint, sr
+
+ uid = Column(Integer, primary_key=True, autoincrement=True) # a primary key integer field (auto incremented)
+
+ location = Column(String) # cluster label
+ sfc = Column(String) # service function chain label
+ sfc_i = Column(String) # service function chain instance identifier
+ sf = Column(String) # service function label
+ sf_i = Column(String) # service function identifier (potentially FQDN)
+ sf_endpoint = Column(String) # service function endpoint (potentially IP address)
+ sr = Column(String) # service router ID - service router that connects the VM to FLAME
diff --git a/src/service/development.ini b/src/service/development.ini
index 390e2a5..18e7f24 100644
--- a/src/service/development.ini
+++ b/src/service/development.ini
@@ -14,9 +14,11 @@ pyramid.default_locale_name = en
pyramid.includes = pyramid_debugtoolbar pyramid_exclog
exclog.ignore =
-## Configuration file path
+# Configuration file path
configuration_file_path = /etc/flame/clmc/service.conf
+# PostgreSQL connection url
+sqlalchemy.url = postgresql://clmc:clmc_service@localhost:5432/whoamidb
# By default, the toolbar only appears for clients from IP addresses
# '127.0.0.1' and '::1'.
@@ -36,7 +38,7 @@ listen = localhost:9080
###
[loggers]
-keys = root, exc_logger, clmcservice
+keys = root, exc_logger, service_logger, sqlalchemy.engine.base.Engine
[handlers]
keys = console, filelog, exc_handler
@@ -48,7 +50,12 @@ keys = generic, exc_formatter
level = INFO
handlers = console
-[logger_clmcservice]
+[logger_sqlalchemy.engine.base.Engine]
+level = INFO
+handlers =
+qualname = sqlalchemy.engine.base.Engine
+
+[logger_service_logger]
level = INFO
handlers = filelog
qualname = service_logger
diff --git a/src/service/production.ini b/src/service/production.ini
index 3e8876b..8ebe666 100644
--- a/src/service/production.ini
+++ b/src/service/production.ini
@@ -14,9 +14,11 @@ pyramid.default_locale_name = en
pyramid.includes = pyramid_exclog
exclog.ignore =
-## Configuration file path
+# Configuration file path
configuration_file_path = /etc/flame/clmc/service.conf
+# PostgreSQL connection url
+sqlalchemy.url = postgresql://clmc:clmc_service@localhost:5432/whoamidb
###
# wsgi server configuration
@@ -32,7 +34,7 @@ listen = *:9080
###
[loggers]
-keys = root, exc_logger, service_logger
+keys = root, exc_logger, service_logger, sqlalchemy.engine.base.Engine
[handlers]
keys = console, filelog, exc_handler
@@ -44,6 +46,11 @@ keys = generic, exc_formatter
level = INFO
handlers = console
+[logger_sqlalchemy.engine.base.Engine]
+level = INFO
+handlers =
+qualname = sqlalchemy.engine.base.Engine
+
[logger_service_logger]
level = INFO
handlers = filelog
diff --git a/src/service/setup.py b/src/service/setup.py
index 4b80091..7bbc332 100644
--- a/src/service/setup.py
+++ b/src/service/setup.py
@@ -46,6 +46,9 @@ requires = [
'pyramid_debugtoolbar',
'pyramid_exclog',
'waitress',
+ 'sqlalchemy',
+ 'zope.sqlalchemy',
+ 'psycopg2',
'influxdb',
'pytest',
]
@@ -80,5 +83,8 @@ setup(
'paste.app_factory': [
'main = clmcservice:main',
],
+ 'console_scripts': [
+ 'initialize_clmcservice_db = clmcservice.initialize_db:main',
+ ]
},
)
\ No newline at end of file
--
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