Convert Volume and Snapshot IDs to use UUID

* Three migrations
  1. create id mappings
  2. convert volume_id and snapshot_id from int to string
  3. change volume/snapshot id's from int to uuid
* DB migration for Volume and Related tables
* Addition of new volume id mapping tables
* Added methods in ec2utils
* Minor tweaks to unit tests
* Other changes to migration to ensure consistency in id's
* Fixed bug in the block-device-mapping table (wasn't setting autoinc)

Change-Id: Ic6c3646e0f01c26467a4a3c20e13eebaa2baa97e

2 files changed, 71 insertions, 17 deletions

diff --git a/nova/api/ec2/cloud.py b/nova/api/ec2/cloud.py
index 8c6a1fdc3..26cc4a70c 100644
--- a/nova/api/ec2/cloud.py
+++ b/nova/api/ec2/cloud.py
@@ -131,7 +131,7 @@ def _parse_block_device_mapping(bdm):
     if ebs:
         ec2_id = ebs.pop('snapshot_id', None)
         if ec2_id:
-            id = ec2utils.ec2_id_to_id(ec2_id)
+            id = ec2utils.ec2_vol_id_to_uuid(ec2_id)
             if ec2_id.startswith('snap-'):
                 bdm['snapshot_id'] = id
             elif ec2_id.startswith('vol-'):
@@ -310,7 +310,7 @@ class CloudController(object):
         if snapshot_id:
             snapshots = []
             for ec2_id in snapshot_id:
-                internal_id = ec2utils.ec2_id_to_id(ec2_id)
+                internal_id = ec2utils.ec2_snap_id_to_uuid(ec2_id)
                 snapshot = self.volume_api.get_snapshot(
                     context,
                     snapshot_id=internal_id)
@@ -336,7 +336,7 @@ class CloudController(object):
         validate_ec2_id(volume_id)
         LOG.audit(_("Create snapshot of volume %s"), volume_id,
                   context=context)
-        volume_id = ec2utils.ec2_id_to_id(volume_id)
+        volume_id = ec2utils.ec2_vol_id_to_uuid(volume_id)
         volume = self.volume_api.get(context, volume_id)
         snapshot = self.volume_api.create_snapshot(
                 context,
@@ -346,7 +346,7 @@ class CloudController(object):
         return self._format_snapshot(context, snapshot)
 
     def delete_snapshot(self, context, snapshot_id, **kwargs):
-        snapshot_id = ec2utils.ec2_id_to_id(snapshot_id)
+        snapshot_id = ec2utils.ec2_snap_id_to_uuid(snapshot_id)
         snapshot = self.volume_api.get_snapshot(context, snapshot_id)
         self.volume_api.delete_snapshot(context, snapshot)
         return True
@@ -853,7 +853,7 @@ class CloudController(object):
             volumes = []
             for ec2_id in volume_id:
                 validate_ec2_id(ec2_id)
-                internal_id = ec2utils.ec2_id_to_id(ec2_id)
+                internal_id = ec2utils.ec2_vol_id_to_uuid(ec2_id)
                 volume = self.volume_api.get(context, internal_id)
                 volumes.append(volume)
         else:
@@ -901,7 +901,7 @@ class CloudController(object):
     def create_volume(self, context, **kwargs):
         size = kwargs.get('size')
         if kwargs.get('snapshot_id') is not None:
-            snapshot_id = ec2utils.ec2_id_to_id(kwargs['snapshot_id'])
+            snapshot_id = ec2utils.ec2_snap_id_to_uuid(kwargs['snapshot_id'])
             snapshot = self.volume_api.get_snapshot(context, snapshot_id)
             LOG.audit(_("Create volume from snapshot %s"), snapshot_id,
                       context=context)
@@ -924,7 +924,7 @@ class CloudController(object):
 
     def delete_volume(self, context, volume_id, **kwargs):
         validate_ec2_id(volume_id)
-        volume_id = ec2utils.ec2_id_to_id(volume_id)
+        volume_id = ec2utils.ec2_vol_id_to_uuid(volume_id)
 
         try:
             volume = self.volume_api.get(context, volume_id)
@@ -937,7 +937,7 @@ class CloudController(object):
     def attach_volume(self, context, volume_id, instance_id, device, **kwargs):
         validate_ec2_id(instance_id)
         validate_ec2_id(volume_id)
-        volume_id = ec2utils.ec2_id_to_id(volume_id)
+        volume_id = ec2utils.ec2_vol_id_to_uuid(volume_id)
         instance_id = ec2utils.ec2_id_to_id(instance_id)
         instance = self.compute_api.get(context, instance_id)
         msg = _("Attach volume %(volume_id)s to instance %(instance_id)s"
@@ -960,7 +960,7 @@ class CloudController(object):
 
     def detach_volume(self, context, volume_id, **kwargs):
         validate_ec2_id(volume_id)
-        volume_id = ec2utils.ec2_id_to_id(volume_id)
+        volume_id = ec2utils.ec2_vol_id_to_uuid(volume_id)
         LOG.audit(_("Detach volume %s"), volume_id, context=context)
         volume = self.volume_api.get(context, volume_id)
 
diff --git a/nova/api/ec2/ec2utils.py b/nova/api/ec2/ec2utils.py
index 1a6bb96bd..045ee12d3 100644
--- a/nova/api/ec2/ec2utils.py
+++ b/nova/api/ec2/ec2utils.py
@@ -18,12 +18,13 @@
 
 import re
 
+from nova import context
 from nova import db
 from nova import exception
 from nova import flags
 from nova import log as logging
-from nova import network
 from nova.network import model as network_model
+from nova import utils
 
 
 FLAGS = flags.FLAGS
@@ -132,15 +133,68 @@ def id_to_ec2_id(instance_id, template='i-%08x'):
     return template % int(instance_id)
 
 
-def id_to_ec2_snap_id(instance_id):
-    """Convert an snapshot ID (int) to an ec2 snapshot ID
-    (snap-[base 16 number])"""
-    return id_to_ec2_id(instance_id, 'snap-%08x')
+def id_to_ec2_snap_id(snapshot_id):
+    """Get or create an ec2 volume ID (vol-[base 16 number]) from uuid."""
+    if utils.is_uuid_like(snapshot_id):
+        ctxt = context.get_admin_context()
+        int_id = get_int_id_from_snapshot_uuid(ctxt, snapshot_id)
+        return id_to_ec2_id(int_id)
+    else:
+        return id_to_ec2_id(snapshot_id, 'snap-%08x')
 
 
-def id_to_ec2_vol_id(instance_id):
-    """Convert an volume ID (int) to an ec2 volume ID (vol-[base 16 number])"""
-    return id_to_ec2_id(instance_id, 'vol-%08x')
+def id_to_ec2_vol_id(volume_id):
+    """Get or create an ec2 volume ID (vol-[base 16 number]) from uuid."""
+    if utils.is_uuid_like(volume_id):
+        ctxt = context.get_admin_context()
+        int_id = get_int_id_from_volume_uuid(ctxt, volume_id)
+        return id_to_ec2_id(int_id)
+    else:
+        return id_to_ec2_id(volume_id, 'vol-%08x')
+
+
+def ec2_vol_id_to_uuid(ec2_id):
+    """Get the cooresponding UUID for the given ec2-id."""
+    ctxt = context.get_admin_context()
+
+    # NOTE(jgriffith) first strip prefix to get just the numeric
+    int_id = ec2_id_to_id(ec2_id)
+    return get_volume_uuid_from_int_id(ctxt, int_id)
+
+
+def get_int_id_from_volume_uuid(context, volume_uuid):
+    if volume_uuid is None:
+        return
+    try:
+        return db.get_ec2_volume_id_by_uuid(context, volume_uuid)
+    except exception.NotFound:
+        raise exception.VolumeNotFound()
+
+
+def get_volume_uuid_from_int_id(context, int_id):
+    return db.get_volume_uuid_by_ec2_id(context, int_id)
+
+
+def ec2_snap_id_to_uuid(ec2_id):
+    """Get the cooresponding UUID for the given ec2-id."""
+    ctxt = context.get_admin_context()
+
+    # NOTE(jgriffith) first strip prefix to get just the numeric
+    int_id = ec2_id_to_id(ec2_id)
+    return get_snapshot_uuid_from_int_id(ctxt, int_id)
+
+
+def get_int_id_from_snapshot_uuid(context, snapshot_uuid):
+    if snapshot_uuid is None:
+        return
+    try:
+        return db.get_ec2_snapshot_id_by_uuid(context, snapshot_uuid)
+    except exception.NotFound:
+        raise exception.SnapshotNotFound()
+
+
+def get_snapshot_uuid_from_int_id(context, int_id):
+    return db.get_snapshot_uuid_by_ec2_id(context, int_id)
 
 
 _c2u = re.compile('(((?<=[a-z])[A-Z])|([A-Z](?![A-Z]|$)))')