Add support for Juju network spaces

This change adds support for binding ceph to specific networks using
Juju network spaces extra-bindings.  The networks supported are:

  - cluster: the Ceph cluster network used for inter-unit
             communication for re-syncs etc.
  - public:  the Ceph public network used by clients to access
             Ceph MON and OSD services.

This is only supported under Juju 2.0.

.gitignore

@@ -4,3 +4,4 @@ bin
 .testrepository
 .tox
 *.sw[nop]
+*.pyc

hooks/ceph_hooks.py

@@ -58,6 +58,7 @@
 from utils import (
     get_networks,
     get_public_addr,
+    get_cluster_addr,
     assert_charm_supports_ipv6
 )
 from ceph_broker import (
@@ -116,6 +117,9 @@ def emit_cephconf():
             cephcontext['public_addr'] = dynamic_ipv6_address
         if not cluster_network:
             cephcontext['cluster_addr'] = dynamic_ipv6_address
+    else:
+        cephcontext['public_addr'] = get_public_addr()
+        cephcontext['cluster_addr'] = get_cluster_addr()
 
     # Install ceph.conf as an alternative to support
     # co-existence with other charms that write this file

hooks/charmhelpers/core/hookenv.py

@@ -976,3 +976,50 @@ def _run_atexit():
     for callback, args, kwargs in reversed(_atexit):
         callback(*args, **kwargs)
     del _atexit[:]
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def network_get_primary_address(relation_id=None,
+                                extra_binding_name=None):
+    """For DEMO only. Juju network-get forcing --primary-address
+       network-get --primary-address currenlty returns a bald string
+       and does not honor --format json"""
+    cmd = ['network-get', '--primary-address']
+    if relation_id:
+        cmd.extend(['-r', relation_id])
+    if extra_binding_name:
+        cmd.extend([extra_binding_name])
+    return subprocess.check_output(cmd).strip()
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def network_get(relation_id=None):
+    """Juju network-get"""
+    cmd = ['network-get', '--format=json']
+    if relation_id:
+        cmd.extend(['-r', relation_id])
+    return json.loads(subprocess.check_output(cmd).decode('UTF-8'))
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def request_address(relation_id=None, address=None, shared=False, token=False):
+    """Juju request-address"""
+    cmd = ['request-address']
+    if relation_id:
+        cmd.extend(['-r', relation_id])
+    if address:
+        cmd.append(address)
+    if shared:
+        cmd.append('--shared')
+    if token:
+        cmd.extend(['--token', token])
+    return subprocess.check_output(cmd).decode('UTF-8')
+
+
+@translate_exc(from_exc=OSError, to_exc=NotImplementedError)
+def release_address(address, relation_id=None):
+    """Juju request-address"""
+    cmd = ['release-address', address]
+    if relation_id:
+        cmd.extend(['-r', relation_id])
+    return subprocess.check_call(cmd)

hooks/utils.py

@@ -13,6 +13,8 @@
     unit_get,
     cached,
     config,
+    network_get_primary_address,
+    log,
     status_set,
 )
 from charmhelpers.fetch import (
@@ -72,6 +74,32 @@ def get_host_ip(hostname=None):
             return answers[0].address
 
 
+@cached
+def get_public_addr():
+    if config('ceph-public-network'):
+        return get_network_addrs('ceph-public-network')[0]
+
+    try:
+        return network_get_primary_address(extra_binding_name='public')
+    except NotImplementedError:
+        log("DEBUG: network-get failed NotImplementedError", "DEBUG")
+
+    return get_host_ip()
+
+
+@cached
+def get_cluster_addr():
+    if config('ceph-cluster-network'):
+        return get_network_addrs('ceph-cluster-network')[0]
+
+    try:
+        return network_get_primary_address(extra_binding_name='cluster')
+    except NotImplementedError:
+        log("DEBUG: network-get failed NotImplementedError", "DEBUG")
+
+    return get_host_ip()
+
+
 def get_networks(config_opt='ceph-public-network'):
     """Get all configured networks from provided config option.
 
@@ -86,10 +114,6 @@ def get_networks(config_opt='ceph-public-network'):
     return []
 
 
-def get_public_addr():
-    return get_network_addrs('ceph-public-network')[0]
-
-
 def get_network_addrs(config_opt):
     """Get all configured public networks addresses.
 

metadata.yaml

@@ -12,6 +12,9 @@ tags:
 peers:
   mon:
     interface: ceph
+extra-bindings:
+  cluster:
+  public:
 provides:
   nrpe-external-master:
     interface: nrpe-external-master

templates/ceph.conf

@@ -1,11 +1,11 @@
 [global]
-{% if old_auth %}
+{%- if old_auth %}
 auth supported = {{ auth_supported }}
-{% else %}
+{%- else %}
 auth cluster required = {{ auth_supported }}
 auth service required = {{ auth_supported }}
 auth client required = {{ auth_supported }}
-{% endif %}
+{%- endif %}
 keyring = /etc/ceph/$cluster.$name.keyring
 mon host = {{ mon_hosts }}
 fsid = {{ fsid }}
@@ -17,17 +17,16 @@ mon cluster log to syslog = {{ use_syslog }}
 debug mon = {{ loglevel }}/5
 debug osd = {{ loglevel }}/5
 
-{%- if ceph_public_network is string %}
+{% if ceph_public_network is string %}
 public network = {{ ceph_public_network }}
 {%- endif %}
 {%- if ceph_cluster_network is string %}
 cluster network = {{ ceph_cluster_network }}
 {%- endif %}
-
-{% if public_addr %}
+{%- if public_addr %}
 public addr = {{ public_addr }}
-{% endif %}
-{% if cluster_addr %}
+{%- endif %}
+{%- if cluster_addr %}
 cluster addr = {{ cluster_addr }}
 {%- endif %}