Merge default

10 files changed, 409 insertions, 26 deletions

diff --git a/docs/rabbitmqctl.1.xml b/docs/rabbitmqctl.1.xml
index 73347cea..522a51ee 100644
--- a/docs/rabbitmqctl.1.xml
+++ b/docs/rabbitmqctl.1.xml
@@ -637,7 +637,7 @@
             </para>
             <para>
               Deleting a virtual host deletes all its exchanges,
-              queues, bindings, user permissions and parameters.
+              queues, bindings, user permissions, parameters and policies.
             </para>
             <para role="example-prefix">For example:</para>
             <screen role="example">rabbitmqctl delete_vhost test</screen>
@@ -895,6 +895,93 @@
     </refsect2>
 
     <refsect2>
+      <title>Policy Management</title>
+      <para>
+        Policies are used to control and modify the behaviour of queues
+        and exchanges on a cluster-wide basis. Policies apply within a
+        given vhost, and consist of a key, pattern, definition and an
+        optional priority. Policies can be set, cleared and listed.
+      </para>
+      <variablelist>
+        <varlistentry>
+          <term><cmdsynopsis><command>set_policy</command> <arg choice="opt">-p <replaceable>vhostpath</replaceable></arg> <arg choice="req"><replaceable>key</replaceable></arg> <arg choice="req"><replaceable>pattern</replaceable></arg>  <arg choice="req"><replaceable>definition</replaceable></arg> <arg choice="opt"><replaceable>priority</replaceable></arg> </cmdsynopsis></term>
+          <listitem>
+            <para>
+              Sets a policy.
+            </para>
+            <variablelist>
+              <varlistentry>
+                <term>key</term>
+                <listitem><para>
+                    The name of the policy.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>pattern</term>
+                <listitem><para>
+                    The regular expression, which when matches on a given resources causes the policy to apply.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>definition</term>
+                <listitem><para>
+                    The definition of the policy, as a
+                    JSON string. In most shells you are very likely to
+                    need to quote this.
+                </para></listitem>
+              </varlistentry>
+              <varlistentry>
+                <term>priority</term>
+                <listitem><para>
+                    The priority of the policy as an integer, defaulting to 0. Higher numbers indicate greater precedence.
+                </para></listitem>
+              </varlistentry>
+            </variablelist>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl set_policy federate-me "^amq." '{"federation-upstream-set":"all"}'</screen>
+            <para role="example">
+              This command sets the policy <command>federate-me</command> in the default virtual host so that built-in exchanges are federated.
+            </para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><cmdsynopsis><command>clear_policy</command> <arg choice="opt">-p <replaceable>vhostpath</replaceable></arg> <arg choice="req"><replaceable>key</replaceable></arg></cmdsynopsis></term>
+          <listitem>
+            <para>
+              Clears a policy.
+            </para>
+            <variablelist>
+              <varlistentry>
+                <term>key</term>
+                <listitem><para>
+                    The name of the policy being cleared.
+                </para></listitem>
+              </varlistentry>
+            </variablelist>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl clear_policy federate-me</screen>
+            <para role="example">
+              This command clears the <command>federate-me</command> policy in the default virtual host.
+            </para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
+          <term><cmdsynopsis><command>list_policies</command> <arg choice="opt">-p <replaceable>vhostpath</replaceable></arg></cmdsynopsis></term>
+          <listitem>
+            <para>
+              Lists all policies for a virtual host.
+            </para>
+            <para role="example-prefix">For example:</para>
+            <screen role="example">rabbitmqctl list_policies</screen>
+            <para role="example">
+              This command lists all policies in the default virtual host.
+            </para>
+          </listitem>
+        </varlistentry>
+      </variablelist>
+    </refsect2>
+
+    <refsect2>
       <title>Server Status</title>
       <para>
         The server status queries interrogate the server and return a list of
diff --git a/src/rabbit_control_main.erl b/src/rabbit_control_main.erl
index a3cbf6e5..424b9808 100644
--- a/src/rabbit_control_main.erl
+++ b/src/rabbit_control_main.erl
@@ -70,6 +70,10 @@
          {clear_parameter, [?VHOST_DEF]},
          {list_parameters, [?VHOST_DEF]},
 
+         {set_policy, [?VHOST_DEF]},
+         {clear_policy, [?VHOST_DEF]},
+         {list_policies, [?VHOST_DEF]},
+
          {list_queues, [?VHOST_DEF]},
          {list_exchanges, [?VHOST_DEF]},
          {list_bindings, [?VHOST_DEF]},
@@ -458,6 +462,28 @@ action(list_parameters, Node, [], Opts, Inform) ->
       rpc_call(Node, rabbit_runtime_parameters, list_formatted, [VHostArg]),
       rabbit_runtime_parameters:info_keys());
 
+action(set_policy, Node, [Key, Pattern, Defn | Prio], Opts, Inform)
+  when Prio == [] orelse length(Prio) == 1 ->
+    Msg = "Setting policy ~p for pattern ~p to ~p",
+    {InformMsg, Prio1} = case Prio of []  -> {Msg, undefined};
+                                      [P] -> {Msg ++ " with priority ~s", P}
+                         end,
+    VHostArg = list_to_binary(proplists:get_value(?VHOST_OPT, Opts)),
+    Inform(InformMsg, [Key, Pattern, Defn] ++ Prio),
+    rpc_call(Node, rabbit_policy, parse_set,
+             [VHostArg, list_to_binary(Key), Pattern, Defn, Prio1]);
+
+action(clear_policy, Node, [Key], Opts, Inform) ->
+    VHostArg = list_to_binary(proplists:get_value(?VHOST_OPT, Opts)),
+    Inform("Clearing policy ~p", [Key]),
+    rpc_call(Node, rabbit_policy, delete, [VHostArg, list_to_binary(Key)]);
+
+action(list_policies, Node, [], Opts, Inform) ->
+    VHostArg = list_to_binary(proplists:get_value(?VHOST_OPT, Opts)),
+    Inform("Listing policies", []),
+    display_info_list(rpc_call(Node, rabbit_policy, list_formatted, [VHostArg]),
+                      rabbit_policy:info_keys());
+
 action(report, Node, _Args, _Opts, Inform) ->
     Inform("Reporting server status on ~p~n~n", [erlang:universaltime()]),
     [begin ok = action(Action, N, [], [], Inform), io:nl() end ||
diff --git a/src/rabbit_mirror_queue_misc.erl b/src/rabbit_mirror_queue_misc.erl
index 4c8406d9..1b487534 100644
--- a/src/rabbit_mirror_queue_misc.erl
+++ b/src/rabbit_mirror_queue_misc.erl
@@ -15,16 +15,26 @@
 %%
 
 -module(rabbit_mirror_queue_misc).
+-behaviour(rabbit_policy_validator).
 
 -export([remove_from_queue/3, on_node_up/0, add_mirrors/2, add_mirror/2,
          report_deaths/4, store_updated_slaves/1, suggested_queue_nodes/1,
-         is_mirrored/1, update_mirrors/2]).
+         is_mirrored/1, update_mirrors/2, validate_policy/1]).
 
 %% for testing only
 -export([suggested_queue_nodes/4]).
 
 -include("rabbit.hrl").
 
+-rabbit_boot_step({?MODULE,
+                   [{description, "HA policy validation"},
+                    {mfa, {rabbit_registry, register,
+                           [policy_validator, <<"ha-mode">>, ?MODULE]}},
+                    {mfa, {rabbit_registry, register,
+                           [policy_validator, <<"ha-params">>, ?MODULE]}},
+                    {requires, rabbit_registry},
+                    {enables, recovery}]}).
+
 %%----------------------------------------------------------------------------
 
 -ifdef(use_specs).
@@ -328,3 +338,40 @@ update_mirrors0(OldQ = #amqqueue{name = QName},
     add_mirrors(QName, NewNodes -- OldNodes),
     drop_mirrors(QName, OldNodes -- NewNodes),
     ok.
+
+%%----------------------------------------------------------------------------
+
+validate_policy(KeyList) ->
+    validate_policy(
+      proplists:get_value(<<"ha-mode">>,   KeyList),
+      proplists:get_value(<<"ha-params">>, KeyList)).
+
+validate_policy(<<"all">>, _Params) ->
+    ok;
+validate_policy(<<"nodes">>, Params) ->
+    validate_params(lists:append(Params),
+                    fun erlang:is_binary/1,
+                    "~p has invalid node names when ha-mode=nodes",
+                    fun (N) -> N > 0 end,
+                    "at least one node expected when ha-mode=nodes");
+validate_policy(<<"exactly">>, Params) ->
+    validate_params(Params,
+                    fun (N) -> is_integer(N) andalso N > 0 end,
+                    "~p must be a positive integer",
+                    fun (N) -> N == 1 end,
+                    "ha-params must be supplied with one number "
+                    "when ha-mode=exactly");
+validate_policy(Mode, _Params) ->
+    {error, "~p is not a valid ha-mode value", [Mode]}.
+
+validate_params(Params, FilterPred, FilterMsg, SizePred, SizeMsg)
+  when is_list(Params) ->
+    case SizePred(length(Params)) of
+        true -> case lists:filter(fun (P) -> not FilterPred(P) end, Params) of
+                    [] -> ok;
+                    X  -> {error, FilterMsg, [X]}
+                end;
+        false -> {error, SizeMsg, []}
+    end;
+validate_params(Params, _, _, _, _) ->
+    {error, "~p was expected to be a list", [Params]}.
diff --git a/src/rabbit_policy.erl b/src/rabbit_policy.erl
index f4c1f42b..4dcce4e0 100644
--- a/src/rabbit_policy.erl
+++ b/src/rabbit_policy.erl
@@ -22,11 +22,13 @@
 
 -include("rabbit.hrl").
 
--import(rabbit_misc, [pget/2, pget/3]).
+-import(rabbit_misc, [pget/2]).
 
 -export([register/0]).
 -export([name/1, get/2, set/1]).
 -export([validate/4, validate_clear/3, notify/4, notify_clear/3]).
+-export([parse_set/5, set/5, delete/2, lookup/2, list/0, list/1,
+         list_formatted/1, info_keys/0]).
 
 -rabbit_boot_step({?MODULE,
                    [{description, "policy parameters"},
@@ -55,7 +57,7 @@ get(Name, EntityName = #resource{virtual_host = VHost}) ->
     get0(Name, match(EntityName, list(VHost))).
 
 get0(_Name, undefined) -> {error, not_found};
-get0(Name, List)       -> case pget(<<"policy">>, List) of
+get0(Name, List)       -> case pget(definition, List) of
                               undefined -> {error, not_found};
                               Policy    -> case pget(Name, Policy) of
                                                undefined -> {error, not_found};
@@ -65,6 +67,81 @@ get0(Name, List)       -> case pget(<<"policy">>, List) of
 
 %%----------------------------------------------------------------------------
 
+parse_set(VHost, Key, Pattern, Definition, undefined) ->
+    parse_set0(VHost, Key, Pattern, Definition, 0);
+parse_set(VHost, Key, Pattern, Definition, Priority) ->
+    try list_to_integer(Priority) of
+        Num -> parse_set0(VHost, Key, Pattern, Definition, Num)
+    catch
+        error:badarg -> {error, "~p priority must be a number", [Priority]}
+    end.
+
+parse_set0(VHost, Key, Pattern, Defn, Priority) ->
+    case rabbit_misc:json_decode(Defn) of
+        {ok, JSON} ->
+            set0(VHost, Key,
+                 [{<<"pattern">>,    list_to_binary(Pattern)},
+                  {<<"definition">>, rabbit_misc:json_to_term(JSON)},
+                  {<<"priority">>,   Priority}]);
+        error ->
+            {error_string, "JSON decoding error"}
+    end.
+
+set(VHost, Key, Pattern, Definition, Priority) ->
+    PolicyProps = [{<<"pattern">>,    Pattern},
+                   {<<"definition">>, Definition},
+                   {<<"priority">>,   case Priority of
+                                          undefined -> 0;
+                                          _         -> Priority
+                                      end}],
+    set0(VHost, Key, PolicyProps).
+
+set0(VHost, Key, Term) ->
+    rabbit_runtime_parameters:set_any(VHost, <<"policy">>, Key, Term).
+
+delete(VHost, Key) ->
+    rabbit_runtime_parameters:clear_any(VHost, <<"policy">>, Key).
+
+lookup(VHost, Key) ->
+    case rabbit_runtime_parameters:lookup(VHost, <<"policy">>, Key) of
+        not_found  -> not_found;
+        P          -> p(P, fun ident/1)
+    end.
+
+list() ->
+    list('_').
+
+list(VHost) ->
+    list0(VHost, fun ident/1).
+
+list_formatted(VHost) ->
+    order_policies(list0(VHost, fun format/1)).
+
+list0(VHost, DefnFun) ->
+    [p(P, DefnFun) || P <- rabbit_runtime_parameters:list(VHost, <<"policy">>)].
+
+order_policies(PropList) ->
+    lists:sort(fun (A, B) -> pget(priority, A) < pget(priority, B) end,
+               PropList).
+
+p(Parameter, DefnFun) ->
+    Value = pget(value, Parameter),
+    [{vhost,      pget(vhost, Parameter)},
+     {key,        pget(key, Parameter)},
+     {pattern,    pget(<<"pattern">>, Value)},
+     {definition, DefnFun(pget(<<"definition">>, Value))},
+     {priority,   pget(<<"priority">>, Value)}].
+
+format(Term) ->
+    {ok, JSON} = rabbit_misc:json_encode(rabbit_misc:term_to_json(Term)),
+    list_to_binary(JSON).
+
+ident(X) -> X.
+
+info_keys() -> [vhost, key, pattern, definition, priority].
+
+%%----------------------------------------------------------------------------
+
 validate(_VHost, <<"policy">>, Name, Term) ->
     rabbit_parameter_validation:proplist(
       Name, policy_validation(), Term).
@@ -80,10 +157,6 @@ notify_clear(VHost, <<"policy">>, _Name) ->
 
 %%----------------------------------------------------------------------------
 
-list(VHost) ->
-    [[{<<"name">>, pget(key, P)} | pget(value, P)]
-     || P <- rabbit_runtime_parameters:list(VHost, <<"policy">>)].
-
 update_policies(VHost) ->
     Policies = list(VHost),
     {Xs, Qs} = rabbit_misc:execute_mnesia_transaction(
@@ -127,13 +200,52 @@ match(Name, Policies) ->
     end.
 
 matches(#resource{name = Name}, Policy) ->
-    match =:= re:run(Name, pget(<<"pattern">>, Policy), [{capture, none}]).
+    match =:= re:run(Name, pget(pattern, Policy), [{capture, none}]).
 
-sort_pred(A, B) -> pget(<<"priority">>, A, 0) >= pget(<<"priority">>, B, 0).
+sort_pred(A, B) -> pget(priority, A) >= pget(priority, B).
 
 %%----------------------------------------------------------------------------
 
 policy_validation() ->
-    [{<<"priority">>, fun rabbit_parameter_validation:number/2, optional},
-     {<<"pattern">>,  fun rabbit_parameter_validation:regex/2,  mandatory},
-     {<<"policy">>,   fun rabbit_parameter_validation:list/2,   mandatory}].
+    [{<<"priority">>,   fun rabbit_parameter_validation:number/2, mandatory},
+     {<<"pattern">>,    fun rabbit_parameter_validation:regex/2,  mandatory},
+     {<<"definition">>, fun validation/2,                         mandatory}].
+
+validation(_Name, []) ->
+    {error, "no policy provided", []};
+validation(_Name, Terms) when is_list(Terms) ->
+    {Keys, Modules} = lists:unzip(
+                        rabbit_registry:lookup_all(policy_validator)),
+    [] = dups(Keys), %% ASSERTION
+    Validators = lists:zipwith(fun (M, K) ->  {M, a2b(K)} end, Modules, Keys),
+    {TermKeys, _} = lists:unzip(Terms),
+    case dups(TermKeys) of
+        []   -> validation0(Validators, Terms);
+        Dup  -> {error, "~p duplicate keys not allowed", [Dup]}
+    end;
+validation(_Name, Term) ->
+    {error, "parse error while reading policy: ~p", [Term]}.
+
+validation0(Validators, Terms) ->
+    case lists:foldl(
+           fun (Mod, {ok, TermsLeft}) ->
+                   ModKeys = proplists:get_all_values(Mod, Validators),
+                   case [T || {Key, _} = T <- TermsLeft,
+                              lists:member(Key, ModKeys)] of
+                       []    -> {ok, TermsLeft};
+                       Scope -> {Mod:validate_policy(Scope), TermsLeft -- Scope}
+                   end;
+               (_, Acc) ->
+                   Acc
+           end, {ok, Terms}, proplists:get_keys(Validators)) of
+         {ok, []} ->
+             ok;
+         {ok, Unvalidated} ->
+             {error, "~p are not recognised policy settings", [Unvalidated]};
+         {Error, _} ->
+             Error
+    end.
+
+a2b(A) -> list_to_binary(atom_to_list(A)).
+
+dups(L) -> L -- lists:usort(L).
diff --git a/src/rabbit_policy_validator.erl b/src/rabbit_policy_validator.erl
new file mode 100644
index 00000000..624c3d54
--- /dev/null
+++ b/src/rabbit_policy_validator.erl
@@ -0,0 +1,37 @@
+%% The contents of this file are subject to the Mozilla Public License
+%% Version 1.1 (the "License"); you may not use this file except in
+%% compliance with the License. You may obtain a copy of the License
+%% at http://www.mozilla.org/MPL/
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and
+%% limitations under the License.
+%%
+%% The Original Code is RabbitMQ.
+%%
+%% The Initial Developer of the Original Code is VMware, Inc.
+%% Copyright (c) 2007-2012 VMware, Inc.  All rights reserved.
+%%
+
+-module(rabbit_policy_validator).
+
+-ifdef(use_specs).
+
+-type(validate_results() ::
+        'ok' | {error, string(), [term()]} | [validate_results()]).
+
+-callback validate_policy([{binary(), term()}]) -> validate_results().
+
+-else.
+
+-export([behaviour_info/1]).
+
+behaviour_info(callbacks) ->
+    [
+     {validate_policy, 1},
+    ];
+behaviour_info(_Other) ->
+    undefined.
+
+-endif.
diff --git a/src/rabbit_registry.erl b/src/rabbit_registry.erl
index e14bbba0..32709d24 100644
--- a/src/rabbit_registry.erl
+++ b/src/rabbit_registry.erl
@@ -107,7 +107,8 @@ sanity_check_module(ClassModule, Module) ->
 class_module(exchange)           -> rabbit_exchange_type;
 class_module(auth_mechanism)     -> rabbit_auth_mechanism;
 class_module(runtime_parameter)  -> rabbit_runtime_parameter;
-class_module(exchange_decorator) -> rabbit_exchange_decorator.
+class_module(exchange_decorator) -> rabbit_exchange_decorator;
+class_module(policy_validator)   -> rabbit_policy_validator.
 
 %%---------------------------------------------------------------------------
 
diff --git a/src/rabbit_runtime_parameters.erl b/src/rabbit_runtime_parameters.erl
index b58b459a..3ee93fa1 100644
--- a/src/rabbit_runtime_parameters.erl
+++ b/src/rabbit_runtime_parameters.erl
@@ -18,9 +18,9 @@
 
 -include("rabbit.hrl").
 
--export([parse_set/4, set/4, clear/3,
-         list/0, list/1, list_strict/1, list/2, list_strict/2, list_formatted/1,
-         lookup/3, value/3, value/4, info_keys/0]).
+-export([parse_set/4, set/4, set_any/4, clear/3, clear_any/3, list/0, list/1,
+         list_strict/1, list/2, list_strict/2, list_formatted/1, lookup/3,
+         value/3, value/4, info_keys/0]).
 
 %%----------------------------------------------------------------------------
 
@@ -32,8 +32,12 @@
                      -> ok_or_error_string()).
 -spec(set/4 :: (rabbit_types:vhost(), binary(), binary(), term())
                -> ok_or_error_string()).
+-spec(set_any/4 :: (rabbit_types:vhost(), binary(), binary(), term())
+                   -> ok_or_error_string()).
 -spec(clear/3 :: (rabbit_types:vhost(), binary(), binary())
                  -> ok_or_error_string()).
+-spec(clear_any/3 :: (rabbit_types:vhost(), binary(), binary())
+                     -> ok_or_error_string()).
 -spec(list/0 :: () -> [rabbit_types:infos()]).
 -spec(list/1 :: (rabbit_types:vhost()) -> [rabbit_types:infos()]).
 -spec(list_strict/1 :: (binary()) -> [rabbit_types:infos()] | 'not_found').
@@ -57,22 +61,29 @@
 
 %%---------------------------------------------------------------------------
 
+parse_set(_, <<"policy">>, _, _) ->
+    {error_string, "policies may not be set using this method"};
 parse_set(VHost, Component, Key, String) ->
     case rabbit_misc:json_decode(String) of
         {ok, JSON} -> set(VHost, Component, Key, rabbit_misc:json_to_term(JSON));
         error      -> {error_string, "JSON decoding error"}
     end.
 
+set(_, <<"policy">>, _, _) ->
+    {error_string, "policies may not be set using this method"};
 set(VHost, Component, Key, Term) ->
-    case set0(VHost, Component, Key, Term) of
-        ok          -> ok;
-        {errors, L} -> format_error(L)
-    end.
+    set_any(VHost, Component, Key, Term).
 
 format_error(L) ->
     {error_string, rabbit_misc:format_many([{"Validation failed~n", []} | L])}.
 
-set0(VHost, Component, Key, Term) ->
+set_any(VHost, Component, Key, Term) ->
+    case set_any0(VHost, Component, Key, Term) of
+        ok          -> ok;
+        {errors, L} -> format_error(L)
+    end.
+
+set_any0(VHost, Component, Key, Term) ->
     case lookup_component(Component) of
         {ok, Mod} ->
             case flatten_errors(Mod:validate(VHost, Component, Key, Term)) of
@@ -100,13 +111,18 @@ mnesia_update(VHost, Component, Key, Term) ->
               Res
       end).
 
+clear(_, <<"policy">> , _) ->
+    {error_string, "policies may not be cleared using this method"};
 clear(VHost, Component, Key) ->
-    case clear0(VHost, Component, Key) of
+    clear_any(VHost, Component, Key).
+
+clear_any(VHost, Component, Key) ->
+    case clear_any0(VHost, Component, Key) of
         ok          -> ok;
         {errors, L} -> format_error(L)
     end.
 
-clear0(VHost, Component, Key) ->
+clear_any0(VHost, Component, Key) ->
     case lookup_component(Component) of
         {ok, Mod} -> case flatten_errors(
                             Mod:validate_clear(VHost, Component, Key)) of
@@ -125,7 +141,8 @@ mnesia_clear(VHost, Component, Key) ->
            end).
 
 list() ->
-    [p(P) || P <- rabbit_misc:dirty_read_all(?TABLE)].
+    [p(P) || #runtime_parameters{ key = {_VHost, Comp, _Key}} = P <-
+             rabbit_misc:dirty_read_all(?TABLE), Comp /= <<"policy">>].
 
 list(VHost)                   -> list(VHost, '_', []).
 list_strict(Component)        -> list('_',   Component, not_found).
@@ -136,7 +153,10 @@ list(VHost, Component, Default) ->
     case component_good(Component) of
         true -> Match = #runtime_parameters{key = {VHost, Component, '_'},
                                             _ = '_'},
-                [p(P) || P <- mnesia:dirty_match_object(?TABLE, Match)];
+                [p(P) || #runtime_parameters{ key = {_VHost, Comp, _Key}} = P <-
+                         mnesia:dirty_match_object(?TABLE, Match),
+                         Comp =/= <<"policy">> orelse
+                             Component =:= <<"policy">>];
         _    -> Default
     end.
 
diff --git a/src/rabbit_runtime_parameters_test.erl b/src/rabbit_runtime_parameters_test.erl
index 5224ccaa..d4d7271e 100644
--- a/src/rabbit_runtime_parameters_test.erl
+++ b/src/rabbit_runtime_parameters_test.erl
@@ -16,9 +16,14 @@
 
 -module(rabbit_runtime_parameters_test).
 -behaviour(rabbit_runtime_parameter).
+-behaviour(rabbit_policy_validator).
 
 -export([validate/4, validate_clear/3, notify/4, notify_clear/3]).
 -export([register/0, unregister/0]).
+-export([validate_policy/1]).
+-export([register_policy_validator/0, unregister_policy_validator/0]).
+
+%----------------------------------------------------------------------------
 
 register() ->
     rabbit_registry:register(runtime_parameter, <<"test">>, ?MODULE).
@@ -36,3 +41,28 @@ validate_clear(_, <<"test">>, _)           -> {error, "meh", []}.
 
 notify(_, _, _, _) -> ok.
 notify_clear(_, _, _) -> ok.
+
+%----------------------------------------------------------------------------
+
+register_policy_validator() ->
+    rabbit_registry:register(policy_validator, <<"testeven">>, ?MODULE),
+    rabbit_registry:register(policy_validator, <<"testpos">>,  ?MODULE).
+
+unregister_policy_validator() ->
+    rabbit_registry:unregister(policy_validator, <<"testeven">>),
+    rabbit_registry:unregister(policy_validator, <<"testpos">>).
+
+validate_policy([{<<"testeven">>, Terms}]) when is_list(Terms) ->
+    case  length(Terms) rem 2 =:= 0 of
+        true  -> ok;
+        false -> {error, "meh", []}
+    end;
+
+validate_policy([{<<"testpos">>, Terms}]) when is_list(Terms) ->
+    case lists:all(fun (N) -> is_integer(N) andalso N > 0 end, Terms) of
+        true  -> ok;
+        false -> {error, "meh", []}
+    end;
+
+validate_policy(_) ->
+    {error, "meh", []}.
diff --git a/src/rabbit_tests.erl b/src/rabbit_tests.erl
index aa48f228..f085c2d5 100644
--- a/src/rabbit_tests.erl
+++ b/src/rabbit_tests.erl
@@ -57,6 +57,7 @@ all_tests() ->
     passed = test_dynamic_mirroring(),
     passed = test_user_management(),
     passed = test_runtime_parameters(),
+    passed = test_policy_validation(),
     passed = test_server_status(),
     passed = test_confirms(),
     passed =
@@ -1039,6 +1040,26 @@ test_runtime_parameters() ->
     rabbit_runtime_parameters_test:unregister(),
     passed.
 
+test_policy_validation() ->
+    rabbit_runtime_parameters_test:register_policy_validator(),
+    SetPol =
+        fun (Key, Val) ->
+                control_action(
+                  set_policy,
+                  ["name", ".*", rabbit_misc:format("{\"~s\":~p}", [Key, Val])])
+        end,
+
+    ok                 = SetPol("testeven", []),
+    ok                 = SetPol("testeven", [1, 2]),
+    ok                 = SetPol("testeven", [1, 2, 3, 4]),
+    ok                 = SetPol("testpos",  [2, 5, 5678]),
+
+    {error_string, _}  = SetPol("testpos",  [-1, 0, 1]),
+    {error_string, _}  = SetPol("testeven", [ 1, 2, 3]),
+
+    rabbit_runtime_parameters_test:unregister_policy_validator(),
+    passed.
+
 test_server_status() ->
     %% create a few things so there is some useful information to list
     Writer = spawn(fun () -> receive shutdown -> ok end end),
diff --git a/src/rabbit_vhost.erl b/src/rabbit_vhost.erl
index 03dfbe24..297fa56f 100644
--- a/src/rabbit_vhost.erl
+++ b/src/rabbit_vhost.erl
@@ -97,6 +97,8 @@ internal_delete(VHostPath) ->
                                           proplists:get_value(component, Info),
                                           proplists:get_value(key, Info))
      || Info <- rabbit_runtime_parameters:list(VHostPath)],
+    [ok = rabbit_policy:delete(VHostPath, proplists:get_value(key, Info))
+     || Info <- rabbit_policy:list(VHostPath)],
     ok = mnesia:delete({rabbit_vhost, VHostPath}),
     ok.