From 8096ee6c79c608fd84e016d5da7663549a95896f Mon Sep 17 00:00:00 2001 From: Rick Harris Date: Thu, 9 Jun 2011 03:35:59 +0000 Subject: Support multiple glance-api servers --- nova/image/__init__.py | 7 ++++++- nova/image/glance.py | 24 +++++++++++++++++------- 2 files changed, 23 insertions(+), 8 deletions(-) (limited to 'nova/image') diff --git a/nova/image/__init__.py b/nova/image/__init__.py index 93d83df24..a27d649d4 100644 --- a/nova/image/__init__.py +++ b/nova/image/__init__.py @@ -22,6 +22,7 @@ import nova from nova import exception from nova import utils from nova import flags +from nova.image import glance as glance_image_service FLAGS = flags.FLAGS @@ -48,6 +49,8 @@ def get_default_image_service(): return ImageService() +# FIXME(sirp): perhaps this should be moved to nova/images/glance so that we +# keep Glance specific code together for the most part def get_glance_client(image_href): """Get the correct glance client and id for the given image_href. @@ -62,7 +65,9 @@ def get_glance_client(image_href): """ image_href = image_href or 0 if str(image_href).isdigit(): - glance_client = GlanceClient(FLAGS.glance_host, FLAGS.glance_port) + glance_host, glance_port = \ + glance_image_service.pick_glance_api_server() + glance_client = GlanceClient(glance_host, glance_port) return (glance_client, int(image_href)) try: diff --git a/nova/image/glance.py b/nova/image/glance.py index 61308431d..b68415844 100644 --- a/nova/image/glance.py +++ b/nova/image/glance.py @@ -20,6 +20,7 @@ from __future__ import absolute_import import datetime +import random from glance.common import exception as glance_exception @@ -39,6 +40,15 @@ FLAGS = flags.FLAGS GlanceClient = utils.import_class('glance.client.Client') +def pick_glance_api_server(): + """Return which Glance API server to use for the request + + Returns (host, port) + """ + host, port = random.choice(FLAGS.glance_api_servers) + return host, port + + class GlanceImageService(service.BaseImageService): """Provides storage and retrieval of disk image objects within Glance.""" @@ -50,13 +60,13 @@ class GlanceImageService(service.BaseImageService): SERVICE_IMAGE_ATTRS = service.BaseImageService.BASE_IMAGE_ATTRS +\ GLANCE_ONLY_ATTRS - def __init__(self, client=None): - # FIXME(sirp): can we avoid dependency-injection here by using - # stubbing out a fake? - if client is None: - self.client = GlanceClient(FLAGS.glance_host, FLAGS.glance_port) - else: - self.client = client + @property + def client(self): + # NOTE(sirp): we want to load balance each request across glance + # servers. Since GlanceImageService is a long-lived object, `client` + # is made to choose a new server each time via this property. + glance_host, glance_port = pick_glance_api_server() + return GlanceClient(glance_host, glance_port) def index(self, context, filters=None, marker=None, limit=None): """Calls out to Glance for a list of images available.""" -- cgit From eda8a1aaa2cf7cc31c7fda4723849feee3bc6766 Mon Sep 17 00:00:00 2001 From: Rick Harris Date: Thu, 9 Jun 2011 14:43:24 +0000 Subject: Fixing the tests --- nova/image/glance.py | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'nova/image') diff --git a/nova/image/glance.py b/nova/image/glance.py index b68415844..f82c0f4a3 100644 --- a/nova/image/glance.py +++ b/nova/image/glance.py @@ -60,14 +60,22 @@ class GlanceImageService(service.BaseImageService): SERVICE_IMAGE_ATTRS = service.BaseImageService.BASE_IMAGE_ATTRS +\ GLANCE_ONLY_ATTRS - @property - def client(self): + _client = None + + def _get_client(self): # NOTE(sirp): we want to load balance each request across glance # servers. Since GlanceImageService is a long-lived object, `client` # is made to choose a new server each time via this property. + if self._client is not None: + return self._client glance_host, glance_port = pick_glance_api_server() return GlanceClient(glance_host, glance_port) + def _set_client(self, client): + self._client = client + + client = property(_get_client, _set_client) + def index(self, context, filters=None, marker=None, limit=None): """Calls out to Glance for a list of images available.""" # NOTE(sirp): We need to use `get_images_detailed` and not -- cgit From e307bf5dd60dc84587f76d88956499ee1f1013fb Mon Sep 17 00:00:00 2001 From: Rick Harris Date: Thu, 9 Jun 2011 21:36:20 +0000 Subject: Fixing code per review comments --- nova/image/glance.py | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'nova/image') diff --git a/nova/image/glance.py b/nova/image/glance.py index f82c0f4a3..5712215bb 100644 --- a/nova/image/glance.py +++ b/nova/image/glance.py @@ -45,7 +45,9 @@ def pick_glance_api_server(): Returns (host, port) """ - host, port = random.choice(FLAGS.glance_api_servers) + host_port = random.choice(FLAGS.glance_api_servers) + host, port_str = host_port.split(':') + port = int(port_str) return host, port @@ -60,7 +62,8 @@ class GlanceImageService(service.BaseImageService): SERVICE_IMAGE_ATTRS = service.BaseImageService.BASE_IMAGE_ATTRS +\ GLANCE_ONLY_ATTRS - _client = None + def __init__(self, client=None): + self._client = client def _get_client(self): # NOTE(sirp): we want to load balance each request across glance -- cgit From 361fd763eb0cf3e62e0184dafd0f4a024e1871f5 Mon Sep 17 00:00:00 2001 From: Rick Harris Date: Thu, 9 Jun 2011 21:50:34 +0000 Subject: Adding caveat --- nova/image/glance.py | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'nova/image') diff --git a/nova/image/glance.py b/nova/image/glance.py index 5712215bb..6e058ab2f 100644 --- a/nova/image/glance.py +++ b/nova/image/glance.py @@ -43,6 +43,10 @@ GlanceClient = utils.import_class('glance.client.Client') def pick_glance_api_server(): """Return which Glance API server to use for the request + This method provides a very primitive form of load-balancing suitable for + testing and sandbox environments. In production, it would be better to use + one IP and route that to a real load-balancer. + Returns (host, port) """ host_port = random.choice(FLAGS.glance_api_servers) -- cgit