Relation support for multi-charm VNFs
Adds support for establishing relations between charms
Signed-off-by: Adam Israel <adam.israel@canonical.com>
Change-Id: I9a0b7725013e06635875cd824e219ab6a023efb3
diff --git a/n2vc/vnf.py b/n2vc/vnf.py
index a1fcfe3..31e4877 100644
--- a/n2vc/vnf.py
+++ b/n2vc/vnf.py
@@ -19,7 +19,7 @@
from juju.controller import Controller
from juju.model import ModelObserver
-
+from juju.errors import JujuAPIError
# We might need this to connect to the websocket securely, but test and verify.
try:
@@ -254,6 +254,100 @@
return self.default_model
+ async def Relate(self, ns_name, vnfd):
+ """Create a relation between the charm-enabled VDUs in a VNF.
+
+ The Relation mapping has two parts: the id of the vdu owning the endpoint, and the name of the endpoint.
+
+ vdu:
+ ...
+ relation:
+ - provides: dataVM:db
+ requires: mgmtVM:app
+
+ This tells N2VC that the charm referred to by the dataVM vdu offers a relation named 'db', and the mgmtVM vdu has an 'app' endpoint that should be connected to a database.
+
+ :param str ns_name: The name of the network service.
+ :param dict vnfd: The parsed yaml VNF descriptor.
+ """
+
+ # Currently, the call to Relate() is made automatically after the
+ # deployment of each charm; if the relation depends on a charm that
+ # hasn't been deployed yet, the call will fail silently. This will
+ # prevent an API breakage, with the intent of making this an explicitly
+ # required call in a more object-oriented refactor of the N2VC API.
+
+ configs = []
+ vnf_config = vnfd.get("vnf-configuration")
+ if vnf_config:
+ juju = vnf_config['juju']
+ if juju:
+ configs.append(vnf_config)
+
+ for vdu in vnfd['vdu']:
+ vdu_config = vdu.get('vdu-configuration')
+ if vdu_config:
+ juju = vdu_config['juju']
+ if juju:
+ configs.append(vdu_config)
+
+ def _get_application_name(name):
+ """Get the application name that's mapped to a vnf/vdu."""
+ vnf_member_index = 0
+ vnf_name = vnfd['name']
+
+ for vdu in vnfd.get('vdu'):
+ # Compare the named portion of the relation to the vdu's id
+ if vdu['id'] == name:
+ application_name = self.FormatApplicationName(
+ ns_name,
+ vnf_name,
+ str(vnf_member_index),
+ )
+ return application_name
+ else:
+ vnf_member_index += 1
+
+ return None
+
+ # Loop through relations
+ for cfg in configs:
+ if 'juju' in cfg:
+ if 'relation' in juju:
+ for rel in juju['relation']:
+ try:
+
+ # get the application name for the provides
+ (name, endpoint) = rel['provides'].split(':')
+ application_name = _get_application_name(name)
+
+ provides = "{}:{}".format(
+ application_name,
+ endpoint
+ )
+
+ # get the application name for thr requires
+ (name, endpoint) = rel['requires'].split(':')
+ application_name = _get_application_name(name)
+
+ requires = "{}:{}".format(
+ application_name,
+ endpoint
+ )
+ self.log.debug("Relation: {} <-> {}".format(
+ provides,
+ requires
+ ))
+ await self.add_relation(
+ ns_name,
+ provides,
+ requires,
+ )
+ except Exception as e:
+ self.log.debug("Exception: {}".format(e))
+
+ return
+
async def DeployCharms(self, model_name, application_name, vnfd,
charm_path, params={}, machine_spec={},
callback=None, *callback_args):
@@ -384,6 +478,10 @@
to=to,
)
+ # Map the vdu id<->app name,
+ #
+ await self.Relate(model_name, vnfd)
+
# #######################################
# # Execute initial config primitive(s) #
# #######################################
@@ -727,23 +825,31 @@
return False
# Non-public methods
- async def add_relation(self, a, b, via=None):
+ async def add_relation(self, model_name, relation1, relation2):
"""
Add a relation between two application endpoints.
- :param a An application endpoint
- :param b An application endpoint
- :param via The egress subnet(s) for outbound traffic, e.g.,
- (192.168.0.0/16,10.0.0.0/8)
+ :param str model_name Name of the network service.
+ :param str relation1 '<application>[:<relation_name>]'
+ :param str relation12 '<application>[:<relation_name>]'
"""
+
if not self.authenticated:
await self.login()
- m = await self.get_model()
+ m = await self.get_model(model_name)
try:
- m.add_relation(a, b, via)
- finally:
- await m.disconnect()
+ await m.add_relation(relation1, relation2)
+ except JujuAPIError as e:
+ # If one of the applications in the relationship doesn't exist,
+ # or the relation has already been added, let the operation fail
+ # silently.
+ if 'not found' in e.message:
+ return
+ if 'already exists' in e.message:
+ return
+
+ raise e
# async def apply_config(self, config, application):
# """Apply a configuration to the application."""
diff --git a/tests/charms/layers/native-ci/layer.yaml b/tests/charms/layers/native-ci/layer.yaml
index edc8839..138d9d3 100644
--- a/tests/charms/layers/native-ci/layer.yaml
+++ b/tests/charms/layers/native-ci/layer.yaml
@@ -1,4 +1,7 @@
-includes: ['layer:basic']
+includes:
+ - 'layer:basic'
+ - 'interface:mysql'
+
options:
basic:
use_venv: false
diff --git a/tests/charms/layers/native-ci/metadata.yaml b/tests/charms/layers/native-ci/metadata.yaml
index 6acf296..0460e48 100644
--- a/tests/charms/layers/native-ci/metadata.yaml
+++ b/tests/charms/layers/native-ci/metadata.yaml
@@ -4,3 +4,9 @@
maintainer: Adam Israel <adam.israel@canonical.com>
subordinate: false
series: ['xenial']
+provides:
+ db:
+ interface: mysql
+requires:
+ app:
+ interface: mysql
diff --git a/tests/charms/layers/native-ci/reactive/native-ci.py b/tests/charms/layers/native-ci/reactive/native-ci.py
index 17bf5f4..9e5fe67 100644
--- a/tests/charms/layers/native-ci/reactive/native-ci.py
+++ b/tests/charms/layers/native-ci/reactive/native-ci.py
@@ -42,3 +42,21 @@
action_set({'output': intval})
finally:
clear_flag('actions.testint')
+
+
+@when('db.joined')
+def provides_db(db):
+ """Simulate providing database credentials."""
+ db.configure(
+ database="mydb",
+ user="myuser",
+ password="mypassword",
+ host="myhost",
+ slave="myslave",
+ )
+
+
+@when('db.available')
+def requires_db(db):
+ """Simulate receiving database credentials."""
+ pass
diff --git a/tests/charms/layers/proxy-ci/metadata.yaml b/tests/charms/layers/proxy-ci/metadata.yaml
index b96abe4..bb00a03 100644
--- a/tests/charms/layers/proxy-ci/metadata.yaml
+++ b/tests/charms/layers/proxy-ci/metadata.yaml
@@ -10,3 +10,9 @@
subordinate: false
series:
- xenial
+provides:
+ db:
+ interface: mysql
+requires:
+ app:
+ interface: mysql
diff --git a/tests/charms/layers/proxy-ci/reactive/proxy_ci.py b/tests/charms/layers/proxy-ci/reactive/proxy_ci.py
index 98b7f96..9c0136e 100644
--- a/tests/charms/layers/proxy-ci/reactive/proxy_ci.py
+++ b/tests/charms/layers/proxy-ci/reactive/proxy_ci.py
@@ -32,3 +32,21 @@
action_set({'output': result})
finally:
clear_flag('actions.test')
+
+
+@when('db.joined')
+def provides_db(db):
+ """Simulate providing database credentials."""
+ db.configure(
+ database="mydb",
+ user="myuser",
+ password="mypassword",
+ host="myhost",
+ slave="myslave",
+ )
+
+
+@when('db.available')
+def requires_db(db):
+ """Simulate receiving database credentials."""
+ pass
diff --git a/tests/integration/test_multivdu_multicharm.py b/tests/integration/test_multivdu_multicharm.py
index e0fb9c7..b879373 100644
--- a/tests/integration/test_multivdu_multicharm.py
+++ b/tests/integration/test_multivdu_multicharm.py
@@ -144,6 +144,11 @@
juju:
charm: proxy-ci
proxy: true
+ # Relation needs to map to the vdu providing or
+ # requiring, so that we can map to the deployed app.
+ relation:
+ - provides: dataVM:db
+ requires: mgmtVM:app
initial-config-primitive:
- seq: '1'
name: test